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Energy simulations results for case studies nZEB renovations

February 2016 Project N°: IEE/12/711/SI2.644745

Project Coordinator: Private Foundation EURECAT (EURECAT)

Leadership of WP3: Private Foundation EURECAT (EURECAT)

Report prepared by EURECAT and NKUA

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Contributors: Eri Vázquez, (FUNDITEC), Roberta Ansuini (PROVAN), Claudia Boude (GEFOSAT), Michael Gerber (ALEM), Lorena Vidas (ANCI), Anna Laura Lacerra (PROVAN), Valeria Vangelista (Eurosportello), Paula Garcia (ENSENYAMENT), Joan Ramon Dacosta (ENSENYAMENT)

Intelligent Energy Europe

The ZEMedS project is co‐funded by the European Union under the Intelligent Energy Europe Programme (Contract No. IEE/12/711).

The sole responsibility for the content of this publication lies with the authors. It does not necessarily reflect the opinion of the European Union. Neither the EACI nor the European Commission is responsible for any use that may be made of the information contained therein.

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Table of Content 1. Introduction ............................................................................................................................. 4 1.1. Overview .............................................................................................................................. 4 1.2. ZEMedS goals in case studies selected ................................................................................ 5 2. AN OVERVIEW OF THE CASE STUDIES SELECTED ..................................................................... 6 2.1. Building type: school typology in the Mediterranean zone ................................................. 9 2.2. Building envelope ............................................................................................................... 10 2.3. Energy building services and current energy values .......................................................... 14 2.4. Health and comfort ............................................................................................................ 18 3. METHODOLOGY FOR THE DEVELOPMENT OF CASE STUDIES ............................................... 19 4. NZEB RENOVATION MEASURES ............................................................................................. 21 4.1. nZEB renovation measures ................................................................................................ 21 5. ENERGY RESULTS AND PAYBACKS ......................................................................................... 27 6. CONCLUSIONS ........................................................................................................................ 34 7. ANNEXES ................................................................................................................................ 36 7.1. nZEB renovation measures for case studies ...................................................................... 36

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1. Introduction

Buildings represent the largest available source of cost effective energy saving and CO₂ reduction potential within Europe. In Mediterranean regions of Italy, Greece, Spain and France, there are approximately 87.000 schools, consuming in a rough estimation around 2Mtoe/year.

The aim to reduce energy consumption in buildings has led to Zero Energy Building (ZEB) concept. EU energy policy encourages MS and Public Authorities to start converting building stock into nearly Zero Energy Buildings and adopting exemplary actions. The Energy Efficiency Directive (EED, 2012/27/EU)1 alongside with the recast of Energy Performance of Buildings Directive (EPBD, 2010/31/EU)2, sets requirements for MS to develop long term renovation strategies for their national building stocks. So far there is not any national law in MED countries that embodies the 2012/27 EED as far as renovation rates of public buildings are concerned.

ZEMedS3 (Zero Energy MEDiterranean Schools) is a 3‐year Project Co‐funded by the European Commission within the Intelligent Energy Europe Programme (IEE), which focuses on the issues related to the refurbishment of Mediterranean schools to nZEB. Currently, there is no clear definition of nZEB concept in national regulation of Mediterranean countries to embody the 2012/27 EED, as far as renovation rates of public buildings are concerned. A roadmap for nZEB, with numerical indicator for energy demand and the share of renewable energy sources is needed.

The aim of ZEMedS project is to map the energy conservation potentials in Mediterranean schools in relation to the environmental quality perspectives. School buildings feature poor indoor air quality while their energy consumption and overall environmental quality could be improved significantly. Many studies have identified the lack of date base, knowledge, experience and best‐practice examples as barriers in refurbishment projects.

The specific objectives of the project are to:

Increase the knowledge and know‐how on the nZEB renovation of schools in Mediterranean climates and give support to several new initiatives on the nZEB refurbishment of schools in Mediterranean climate regions;

Promote the necessary actions for the renovation of school buildings in a Mediterranean climate to be nearly zero‐energy buildings;

Ensure a reduced energy demand, to be partially covered by renewable energy sources and, at the same time, guarantee a good indoor environment that will impact positively on occupants’ health and result in higher learning outcomes for the pupils concerned;

The project covers a complete renovation path, tackling strategies for the envelope, the systems and renewable energy applications as well as the energy management and users' behaviour. In this context, the results are presented with case studies of school buildings that have been analyzed in terms of the energy efficiency and cost optimality so as to define a detailed renovation action plan.

1.1. Overview

A typical Mediterranean school built in the period 60‐80’s consumes roughly 100kWh/m2/y (final energy); counts up a great number of overheating hours with glare problems and low ventilation rates.

1 http://eur‐lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2012:315:0001:0056:en:PDF

2 http://eur‐lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:153:0013:0035:EN:PDF

3 http://www.zemeds.eu/

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Even if the building stock is quite varied; there are a number of schools that require holistic renovation in order to reduce energy bills and improve learning environment. The design phase is a crucial step to include criteria concerning both energy performance and indoor environmental quality (IEQ). Moreover, all the actors and users concerned should be involved during this phase with the motivation to have a high performance building.

The development of new toolkits, case studies and tendering specifications are some of the key outputs that will help setting up successful renovation procedures. The aim of these actions is to ensure a reduced energy demand, to be partially covered by renewable energy sources and, at the same time, offer a good indoor environment that will effect positively occupants’ health and result in higher learning outcomes for the pupils concerned.

ZEMedS gives priority to deep renovation approach; nonetheless well‐designed step‐by‐step procedures can pave the way to nZEB when problems of funding or schedule are encountered. In this context, this paper presents the first results of ZEMedS toolkits and case studies. Toolkits are addressed to building designers and policy makers and contain technical and financial resources, whereas case studies are real school buildings that have been energy and cost‐analyzed so as to define specific renovation strategies. These include energy upgrade of the envelope, enhanced ventilation, re‐sizing of heating and lighting equipment, installing renewable energy, controls and user behavior. The developed material will support mentoring and dissemination activities among the target groups, having an impact within and beyond the project duration.

The aim of the simulations was to evaluate the energy performance, impact, applicability, cost, time efforts, etc. associated to NZEB renovation of these schools. The ZEMeds project intents to elucidate the relationship between nearly zero‐energy and cost‐optimal measures and to develop an argumentation on how to ensure a smooth transition from current MED schools to nearly zero energy school buildings.

1.2. ZEMedSgoalsincasestudiesselected

The aim was to thoroughly analyse the transition from current MED schools to nearly zero energy school buildings in terms of energy efficiency and cost optimality. In order to have a common framework to support the replication potential to other countries, a common methodology has been developed. Τhe ten case studies (two school buildings per participant) have been selected according to the following criteria:

To ensure replication and savings potential;

To have energy data for the last three years available (energy bills or measured data with energy meters are acceptable);

To be a priority for refurbishment for the public institutions of the regions

Α nearly Zero Energy Building (nZEB) should have a very high energy performance and the very low amount of energy required should be covered to a significant extent by renewable energy sources.

As energy strategies contribute correspondingly to better architectural concepts, the case studies have been examined in a holistic way. The energy consumption of these buildings have been analysed and simulated with dynamic software tools, including the solutions issued from the developed nZEB toolkits and the uses indicated in EPBD recast – NZEB definition (heating, lighting, domestic hot water, etc.). Comfort criteria also have been examined. Specific simulations have been performed to dimension RES installations, in order to cover the resulted low energy demand. The paybacks of the measures for the case studies have been calculated. High energy efficiency renovations are often associated to high construction costs, but there is no reliable data about how much higher are these costs.

Specifically, in ZEMedS project the following requirements have been set in order to define a nZEB definition for a school definition:

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Requeriment 1: CPE‐ProdRES≤ 0 Primary energy consumption yearly (heating, cooling, ventilation, DHW and lighting) is produced by local renewable energies.

Requeriment 2: CFE≤ 25 kWh/m2 y FE consumption yearly (heating, cooling, ventilation and lighting) per conditioned area

Requeriment 3: Indoor air quality guaranteed (CO2≤1000 ppm) and temperature above 28ºC ≤40 hours yearly during occupancy

2. ANOVERVIEWOFTHECASESTUDIESSELECTED

The following list resumes the responsible for the administration of the schools in each area and the educational age range available in their building stock:

Catalonia, Department d’Ensenyament, Elementary and secondary schools;

Toscana, ANCI Toscana, Elementary and lower secondary;

Ancona, Province of Ancona, Upper secondary;

Peristeri, Municipality of Peristeri, Elementary and secondary;

Montpellier, No public responsible (Municipality) in the consortium., ALEM & GEFOSAT, Elementary and secondary

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SCHOOL_ENERGY DATA_TEMPLATE_we

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Name of school Location Educational age Year of construction (brief note of last

upgrade in brackets)

Conditioned net floor area

Miguel Hernandez School

Badalona, Catalonia, Spain

Pre‐school and Primary school (ages 3‐11/12)

1979 1147

Sta. Maria Avià School Avià, Catalonia, Spain Pre‐school and Primary school (ages 3‐12)

1977 1366

13th‐33th Primary School

Peristeri, Greece Primary school (ages 5‐12)

Buildings 1, 2, 3: 1977

Building 4: 2000

2005

25th Primary School & Kindergarten

Peristeri, Greece Kindergarten and Primary school (ages 5‐12)

1982 1030

ITC Benincasa Ancona, Marche, Italy High Secondary School (ages 14‐19)

1975‐1977 4942

ITC Einstein Loreto, Marche, Italy High Secondary School (ages 14‐19)

1966 2998

ITC Salvetti Colle di Val d’ Elsa, Tuscany, Italy

Primary school (ages 6‐11)

early 60s 2300

Don Milani Primary School

San Miniato Basso, Tuscany, Italy

Primary school (ages 6‐11)

1982 1265

Salamanque Group School

Montpelier, France Kindergarten and Primary school (ages 3‐12)

1965 2303

Langevin Wallon School Group

Bédarieux, France Pre‐school and Primary school (ages 3‐11)

The older building was constructed before 1900 and partially renovated in 1999.

3445

According to the Köppen classification, the Mediterranean climate can be attributed to an area where: (i) the mean temperature of the coldest month is between –3 and 18oC; (ii) the summer season is generally dry and the rainfall amount of the wettest month is at least three times greater than that of the driest month; (iii) the mean temperature of the warmest month is above 22oC; (iv) the mean annual rainfall amount (in mm) is higher than 20 times the mean annual temperature in degrees Celsius (Lavee et al, 1998). The Mediterranean Sea contributes to the temperate warm climate, retaining heat in summer and releasing it in winter. The majority of the regions with Mediterranean climates have relatively mild winters and hot summers. Although significant variations can be found among the places that satisfy the Mediterranean climate criteria, the countries bordering the basin share some similarities: in almost all the coastline cities, the minimum yearly average temperature is between 5–10oC and the maximum is between 27–34oC. Another characteristic of the Mediterranean climate is that the higher the maximum air temperature, the wider the average temperature fluctuation of the hottest month is. Moreover, inland locations tend to have a more severe climate, with lower temperatures during winter and higher temperatures during summer. For the past few decades there has been a sizeable increase in summer cooling demand in the Mediterranean area, especially in urban areas (Santamouris et al, 2001). Global warming is expected to adversely affect both the environment and human activities in the Mediterranean area, with scenarios for average yearly air temperatures predicting an increase between 2.2 and 5.1oC by 2100, or even sooner than that (Hanson et al., 2007). According to the IPCC (2007), an average temperature rise above 1.5oC is likely to have severe impacts in local environments and ecosystems, while increased temperatures are expected to bring about longer heat waves, decreased precipitation and a longer summer in general.

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2.1. Buildingtype:schooltypologyintheMediterraneanzone

School buildings typologies are quite varied in Spain. School buildings in Catalonia, especially those built up during 80s, count generally on a brick, heavy wall (with air gap) with medium to large glazed façade, according to the construction period, and a horizontal roof. Only in some exceptions, and in mountain regions, roofs are pitched. In general, school classrooms (pupils from 6‐17 years) are oriented to North face of the building and kindergarten classrooms are oriented to the South and protected by a 3 meters porch. Schools built before the first thermal regulation dating back from 1979 lack from any insulation, and those built between 1980 and 2006 count poor requirements regarding thermal insulation. It can be expected that older schools consume more energy, but, for example in Catalonia, schools built until 1980 have higher compactness than those built since this date, so it cannot be taken for granted. Last decades, in Catalonia, there has been a tendency to increase the development of the envelopes and the glazed proportion of the façades. Regarding construction materials, in some cases precast elements (including thermal insulation when later than 1980) have been used in façades. Regarding the roof, this one is generally made of a concrete slab. So, buildings usually have high thermal inertia. Heating system is generally a gas boiler and only some rural schools are equipped with an oil boiler. Heat distribution is done by water radiators. Only in the gyms, a fan coil connected to the boiler is the generally system used. Solar protections are very common. Generally, windows are equipped with sunscreen grills and sometimes with external roller shutters (in oldest buildings). There are additionally overhangs and porches, too. Nowadays, classroom windows are in general aluminium sliding windows. Their thermal properties are varied, from single glazing and no thermal break up to double glazed with thermal break for the recent replaced windows. Finally, integration of solar energy has been already done in some particular cases (see section “energy consumption”) and for nZEB purposes it could be easily done on the existing flat roofs, when they are accessible. Sometimes, access to the roof may be a technical barrier.

The Greek school buildings are divided into two main categories: those that were built before 1960 and are usually stone with a wooden roof and the ones that were built after 1960 and represent typologies of Greek School Buildings Organisation SA (SBO). These typologies generally have similar construction features in all climatic zones of the country; are built with concrete and bricks and have metal frames. The different typologies show many similarities mainly in construction but also in the proportions of classes, corridors and other spaces. Basic differences usually occur in the number and arrangement of classrooms. The design may be linear or Γ shaped, or less commonly Π shaped. Commonly, the schools encountered in compact arrangement, with rooms arranged around a central inner space. The linear buildings and those that are arranged in Γ shaped, showing the rooms face in the yard, or outdoor with an enclosed hallway toward the rear or, more rarely, open hallway from the main side. The typologies appear with 1, 2, or 3 floors according to the school building program.

A "typical” Hellenic school building has the following architectural characteristics: a two‐floor school building with an average floor height between 3 and 4m, no basement, rectangular shape, the main corridor running inside the building in front of the classrooms, conventional construction, roof made of slate and schoolyard extending outside the main building.

Considering the construction year of Italian Schools, 5.6% was built before 1900, 15.0% between 1901 and 1940, 40.7% between 1941 and 1974, 29.2% between 1975 and 1990, 4.70% between 1991 and 2000, 4.8% between 2001 and 2012. Only 0.6% of the buildings were designed following Sustainable Building Criteria. About 50% of the school buildings include a gymnasium.

In French Mediterranean climate, there are 2,066 pre‐schools and 4,057 primary schools, so 12% of the stock in France. There is not much information on the typology of these buildings. However, building schools has undergone several phases and several laws which determined constructive and architectural

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features. The first main phase begins in 1881, when public schooling became free, mandatory and secular. This led to the building of numerous schools, often dependant on the town hall. Building regulations were set. These schools, named “Jules Ferry” have been mostly built of red brick and stone. After the WWI, in the 1930’s, an increase in building schools took place. Schools built during this period often have a symbolic character of modernity: reinforced concrete buildings equipped with continuous canopies and metallic windows, for more space and more indoor lighting. Following the WWII, with the re‐building of towns and the demographic explosion, another boom in school building occurred. This led to a policy of standardization and industrialization. A construction program was based on standard plans: schools were built according to a particular frame to unify dimensions and reduce the cost through the use of prefabricated elements. Then, schools have been built on 2 or 3 levels, with standardized windows uniformly aligned on facades. In 1970, new instructions were given: build one‐storey schools or one‐level schools and incorporate new locals : libraries, workshops areas, rest rooms, outdoor games and green spaces.

2.2. Buildingenvelope

Miguel Hernandez School:

Building component

Brief description U value (W/m2K)

Wall Brick wall with wall cavity. No insulation

1.3

Windows and exterior doors

Single‐glazed windows with aluminium frames with thermal bridge

Ug=5.7 Uf=4

Roof Ventilated roof, sloping and supported by partition walls on the first floor celling with no insulation

2.5

Ground Air chamber for ventilation underneath floor structure. No insulation

1.9

Solar protection Exterior roller shutters ‐

Sta. Maria Avià School

Building component


Wall Wall 1: Brick wall. Air cavity. Wall 2: Brick wall. No insulation. Wall 3: Brick wall. No insulation.

1/1.98/1.41


Double‐glazed windows with aluminium frames with thermal bridges

Ug=3.3 Uf=4

Roof Pitched roof sloping and supported by partition walls on the first floor celling with no insulation

1.3

Ground Suspended concrete slab. No insulation

2.2


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13th‐33th Primary School:

Building component


Wall Concrete and brick wall with in between cavity. No insulation

1.7


Single‐glazed windows with aluminum frames with thermal bridges

Ug=5.7 Uf=5.7

Roof Asphalt covered flat roof. No insulation.

0.9

Ground Concrete slab with mosaic finish. No insulation.

3.1

Solar protection ‐ ‐

25th Primary School & Kindergarten:

Building component


Wall Concrete and brick wall with in between cavity. No insulation

1.7


Single‐glazed windows with aluminum frames with thermal bridges

Ug=5.7 Uf=5.7

Roof Asphalt covered flat roof. Limited EPS insulation

0.9

Ground Concrete slab with mosaic finish. No insulation.

3.1


ITC Benincasa:

Building component


Wall Brick wall with wall cavity. No insulation

1.17


Single‐glazed windows with aluminium frames with thermal bridge

Ug=5.7 Uf=5.7

Roof Insulated terrace roof 0.42

Ground Hollow block. No insulation. 0.9


ITC Einstein:

Building component


Wall Brick wall with wall cavity 1


Single‐glazed windows with wooden frames

Ug=5.7 Uf=3

Roof Roof with insulation and waterproofing

0.4

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Ground Hollow block. No insulation. 0.9


ITC Salvetti:

Building component


Wall Brick wall

1.5‐2.0


Double‐glazed windows 4/6/4 low‐e with aluminum frames

Ug=3 Uf=4

Roof Roof made of reinforced concrete

2.6

Ground Concrete

3.9


Don Milani Primary School:

Building component


Wall Brick wall

1.5‐2.0


Double‐glazed windows 4/6/4 with aluminum frames without thermal break

Ug=2.8 Uf=4

Roof Roof with rock wool and corrugated steel roofing sheets

0.5

Ground Expanded clay aggregate 1.7


Salamanque Group School (France): Building

component Brief description U value (W/m2K)

Primary building

Wall Primary school: Panels walls without insulation and cinderblock walls without insulation. Pre‐school: Panels walls without insulation and cinderblock walls with internal insulation.

2.7/3.1

2.7/0.23


20 years old double glazing windows 4/6/4 with aluminium frame with no thermal bridge. 5 years old low‐e double glazing windows and exterior doors 4/16/4 with aluminium frame with thermal bridge.

Ug=3.3 Uf=5.7

Ug = 1.9 Uf=4

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Roof Primary school: Flat roof with insulation Pre‐school: Flat roof without insulation

0.19

3.2

Pre‐school building

Ground Ground floor without insulation

2.2


Langevin Wallon Group School (France):

Building component Brief description U value (W/m2K)

LW1 building

LW2 building

Pre‐school building

Gym building

Wall LW1: Brick walls without insulation and concrete block walls without insulation LW2: Composite stone brick wall with wall cavity and Brick walls without insulation (restaurant) Pre‐school: Brick walls without insulation and concrete block walls without insulation Gym: Concrete blocks walls without insulation and insulated metallic cladding walls and insulated concrete block walls

1.42/2.16

1.15/1.42

1.42/2.16

2.52/0.38/0.22

Window LW1: Double‐glazed windows 4/8/4 with aluminium frame with thermal bridge and single‐glazed windows with wood frame in corridors and staircases LW2: Double‐glazed windows 4/10/4 with aluminium frame with thermal bridge and single‐glazed windows with wood frame in corridors and staircases Pre‐school: Double‐glazed windows 4/10/4le with aluminium frame with thermal break and single‐glazed windows with wood frame

Ug=3.6/5.7 Uf=4/3

Ug=3.6/5.7 Uf=4/3

Ug=3/5.7 Uf=4/3

Roof LW1: Insulated flat roof (insulation panels 25mm), insulated flat roof (insulation panels 80mm) in corridors and flat roof without insulation LW2: Insulated roof in attic floor and insulated flat roof (restaurant) Pre‐school: Flat roof without insulation

0.84/0.4/2.28

0.15/0.84

2.28

Ground LW1, LW2: Floor on crawl space without insulation and exterior floor on yard without insulation Pre‐school: Floor in contact with a basement without insulation and floor in contact with a garage without insulation and exterior floor on yard without insulation

1.4/2.5

1.4/1.58/2.5

Exterior door LW1, LW2, pre‐school: Single‐glazed with aluminium frames and wood frames

1.4/1.58/2.5

Solar protection Partially existing exterior slats in some windows.

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2.3. Energybuildingservicesandcurrentenergyvalues

Miguel Hernandez School:

Energy services Brief description

heating Natural gas boiler of 95 kW for heating in primary school, and a natural gas boiler of 24 kW for heating and DHW in pre‐school building. The terminal units are mainly radiators.

Lighting Mainly, T8 FL 58Wx2. T8 FL 36W in corridors and T8 FL 36Wx2 in toilets

DHW Electric heater of 150l for DHW in kitchen of primary school. Natural gas boiler of 24 kW for the heating and DHW in pre‐school building.

Appliances 38 computers 4 projector of 280 W 4 printers of 1000 W 2 copiers of 1850 W distributed in offices 1 vending coffee machine of 1500 W 1 server of 250 W

Cooking/kitchen 1 electric heater for meals 2600 W 1 refrigerator of 200 W and 3 domestic fridges 2 microwave of 800 W 1 dishwasher of 3600 W 1 coffee machine of 4700 W

Energy values (kWh/m2 y) Natural gas: 92 Electricity: 42

Energy costs (euros/y) Natural gas: 6363 Electricity: 8768

Sta. Maria Avià School:


Heating Natural gas boiler of 95 kW for heating in primary school, and a natural gas boiler of 24 kW for heating and DHW in pre‐school building. The terminal units are mainly radiators.

Lighting Mainly, luminaries of TL‐D 2X36W fluorescent lamps (low ‐ pressure mercury discharge).

DHW Propane boiler in the kitchen for cooking service, and electric heaters for DHW in pre‐school.

Appliances 49 computer equipment, mainly distributed in the library, offices and classrooms; computer equipment (1 tower PC 70 W and 1 TFT monitor) and 1 projector 450 W in each classroom. 16 total number of sound equipment 36 W in classrooms. 2 Ink printers and 1 laser printer 550 W placed in the library and offices. 2 copiers and 1 scanner distributed in offices. 1 land server 250 W.

Cooking/kitchen 1 dishwasher of 3600 W 2 cold rooms of 1500 W 2 frezzers of 270 W 3 Kitcken extractor fan of 2500 W 1 microwave of 900 W

Energy values (kWh/m2 y) Fuel: 109 Electricity: 34

Energy costs (euros/y) Fuel: 13,411 Electricity: 9,044

13th‐33th Primary School:


Heating 2 Oil boilers (256 kW + 46 kW) supplying radiators. Central heating system. Manual control.

Lighting Mainly, T8 2x26 W and T8 2x58 fluorescent tubes controlled by users

DHW ‐

Appliances Office equipment in teachers’ offices

Cooking/kitchen ‐

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Energy values (kWh/m2 y) Diesel: 25 Electricity: 12

Energy costs (euros/y) Diesel: 5,762 Electricity: 1,764

25th Primary School & Kindergarten:


Heating 1 Oil boiler (256 kW) supplying radiators. Central heating system. Manual control. Heat pumps for cooling only at the teachers’ offices.

Lighting Mainly, T8 2x26 W and T8 2x58 fluorescent tubes controlled by users

DHW ‐

Appliances Electronic boards and computer equipment in classrooms and computer lab Office equipment in teachers’ offices

Cooking/kitchen ‐

Energy values (kWh/m2 y) Diesel: 30 Electricity: 15

Energy costs (euros/y) Diesel: 3,234 Electricity: no data

ITC Benincasa:


Heating 3 natural gas boilers. Two of them are dedicated to space heating (387 kW, 645 kW), while the other one is smaller and is dedicated to DHW. The terminal units are mainly radiators. The only exception are 6 ventilation convector heaters (3.5 kW), used in some offices at level 0 and 8 unit heaters (12 kW) in the gymnasiums. Manual regulation is managed by a Service Company that has to be called in case of need. 1 heat pump outdoor unit, located in the terrace at level 1, and a network of furthermore 2 autonomous air conditioner (1660 W) are installed in two rooms at level 1: in the server room and in the teacher room

Lighting Mainly, T8 FL 58W/840 x1 (75 units), T8 FL 58W/840 x2 (201 units) and metal halide 400W/645 (40 units).

DHW Natural gas boiler for the domestic hot water (84 kW).

Appliances 26 computer equipment; computer equipment (tower PC of 100 W and monitor of 40 W) 21 interactive projector of 340 W in almost all classrooms. 7 B/W laser printer and 9 colour laser printer of 380 W. 2 copiers of 1500 W distributed in offices.

Cooking/kitchen Little bar at lebel 1 2 electric oven of 800 W 4 refrigerator of 750 W 1 coffee machine of 4700 W


Energy costs (euros/y) Natural gas: 51,836 Electricity: 26,990

ITC Einstein:


Heating 2 natural gas boilers (347 kW). A secondary system, fed by a separated boiler (cargomax 31) placed on the terrace roof (first level) provide heating to the gymnasium, through two wall mounted air heaters. All the other spaces of the school are heated through radiators, fed by the two boilers placed in the thermal central.

Lighting Mainly, fluorescent tubes controlled by users

DHW DHW is present just in the Gym, managed through the CARGOMAX 31 boiler

Appliances Lab: PC, Projector, Printer Office: PC, Printer, Copy Machine Gym: PC, Refrigerator, Dryer

Cooking/kitchen ‐

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Don Milani Primary School:


heating Natural gas boiler 456 kW

Lighting Mainly, fluorescent tubes controlled by users 2x18W fluorescent tubes in all spaces

DHW Boiler 27 kW

Appliances ‐

Cooking/kitchen Kitchen equipment


Energy costs (euros/y) 64,160

Salamanque Group School (France):


Heating 2 natural gas boilers (230 kW each) situated in the primary school feeds pre‐school. Electric fans are installed in some spaces.

Lighting Primary school: T8 fluorescents 18Wx4 and T8 fluorescents 36Wx2 in classrooms. T5 fluorescents 14Wx3 in offices. T8 fluorescents 36Wx2 in corridors, staircases and toilets. Pre‐school: T8 fluorescents 18Wx4 in classrooms and corridors. LBC 15Wx1, LBC 15Wx2 in offices and toilets.

DHW Primary: 2 electric heaters of 75L (teacher room) and 300L (kitchen) Pre‐school: 1 electric heater of 200L

Appliances Primary: 2 printers/copiers, 27 computers (1 computer/classroom) Pre‐school: 1 printers/copiers, 9 computers (1 computer/classroom)

Cooking/kitchen Primary: Just catering. 1 electric oven of 6kW, 1 refrigerator of 150W, 1 dishwasher of 10kW. Pre‐school: no cooking service



Langevin Wallon School Group:


Heating A central boiler (400 kW) situated in the basement of the LW1 feeds the LW1 building, a substation located in LW2 building (which feeds LW2 and pre‐school) and part of another building. The gym is equipped with 2 gas radiant and 2 electric heaters in the locker room. They are regulated manually.

Lighting LW1: fluorescents 36Wx2, fluorescents 36Wx1, fluorescents 58Wx2, lamps 18W in corridors with presence detector and incandescent bulbs 100W. Standard class: 12 units of fluorescent 36Wx2 and 1 unit fluorescent of 36Wx1. LW2: fluorescents 36Wx2 (119 units), fluorescents 36Wx1 (14 units), lamps 18Wx4 (12 units), incandescent bulbs 100W (44 units) and lamps 18W in corridors with presence detector (23 units). Standard class: 12 units of fluorescent 36Wx2 and 1 unit of fluorescent 36Wx1. Pre‐school: fluorescents 58Wx2 (6 units) and T8 fluorescent 18Wx4 (33 units). Standard class: 5 units of T8 fluorescent of 18Wx4. Gym: fluorescents 36Wx2 (4 units), lamps 400W (10 units), neon 60W (1 unit) and halogen spotlights 35W (18 units).

DHW LW1: 3 electric heaters of 1200 W LW2: Electric heater of 830 W. Also a heat pump (1200 W, COP 3.6) in LW2 in sub‐station Pre‐school: Electric heaters 2400 W+2000 W in kitchen and toilets Gym: Electric heater 2400 W in changing‐room

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Appliances LW1: 2 printers/copiers, 20 computers, 2 TV, and 1 projector LW2: 2 photocopiers, 13 computers, 1 TV and 1 internet box. 1 washing machine and 1 dryer Pre‐school: 3 computers and 1 printer Gym: no appliances

Cooking/kitchen LW1: 2 fridges, 2 microwaves and 1 stove with 4 plates and oven (electric) LW2: 2 gas cooking range, 5 freezer cabinets, 1 oven, 2 pans, 1 peeling machine, 1 coffee machine, 1 fridge and 1 microwave. Pre‐school: 1 fridge, 1 stove with 4 plates and oven (electric), 1 microwave and 1 washing machine



Existing school buildings:

According to invoice information of the case studies, the energy consumptions of existing buildings are distributed like:

Figure 1. Final energy of existing schools (data from invoice information)

From the information of existing energy consumption can be seen that:

In all cases studied, the higher energy consumption in schools appears to be in heating (more than the 65% of the energy consumption) supported mainly by boilers of natural gas (methane) or oil (Greek schools); central heating systems supplying radiators and of manual control are the most common.

Low consumption of cooling; only in some cases (Primary school 25 th, ITC Benincasa, Sta. Maria Avià School) and used in some administration offices, at the teachers’ offices and library, but no in classrooms.

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Mainly, the use of DHW in schools is low (around 2 to 7 kWh/m2) and it is restricted in pre‐schools toilets, kitchens and gyms toilets. Electric heaters and gas boilers are used. Specifically, no DHW in the Greek cases studied, however existing DHW in high secondary school toilets in Italian case studies. There is one case study (ITC Benincasa) which DHW service is supposed to be higher (around 22 kWh/m2) because the use of the gym used in different slots hours and managed by external sport association from 16.00 to 23.00.

In relation to the ventilation, the schools are ventilated by the opening of windows.

2.4. Healthandcomfort

In general, natural ventilation is the existing solution for ventilation in European schools. Nevertheless, this one does not guarantee a good indoor air quality and the tendency is to implement “hybrid” solutions (natural and mechanical ventilation) in order to offer a guarantee and to take advantage of the external air conditions when they are convenient.

In France, the existing schools use natural ventilation. For low energy schools, it is used a mix of natural and mechanical ventilation (only few projects include heat recovery). Currently, there is the requirement that local authorities carry out measures of IAQ in schools. They have to demonstrate that there is a good IAQ. When it is not good, measures have to be implemented to improve it. Since 2001, through the national plan about health and environment (Plan National Santé Environment (PNSE)), the Indoor Air Quality Observatory (OQAI) carries out studies and measures. Particularly, specific studies were led between 2006 and 2009, while in 2011 was launched a national campaign to measure indoor air in order to know its quality in scholar buildings.

In Spain, “RITE” regulation requires high ventilation rates for new or big renovations of school buildings (72 m3/h; around 7‐8 renovations/hour). A mechanical system is required, with heat recovery obliged when a certain rate is achieved. For most new school buildings this is applied. In Catalonia, the rate is slightly reduced with Catalan Energy Agency (ICAEN) agreement when it is justified with the corresponding Spanish norm (UNE).

In Italy, since 1975 a mechanical ventilation system is required for new school buildings, with too strict requirements, so just around 5% of buildings follow this regulation. For low energy schools, they are using CO2 sensors, which are easy‐integrated and allow easy management of ventilation rates. For a particular school, integrating CO2 sensors within the ventilation system, for 20 classrooms, had a cost around 1000 €. Real success cases count on mechanical systems and user behaviour at the same time: pupils open the windows between courses and mechanical ventilation works during the course with the sensor inputs. In some particular cases, a “flag” system indicates when extra ventilation is needed and then windows are opened. In Italy, official ventilation rates deal with noise problems.

In Greek schools, there is no mechanical ventilation at all. New regulations (adopted following EPBD) require around 8 l/s/person. In some schools, the solution adopted then is a fan in the window. Studies have been performed in Greek schools showing that IAQ is not guaranteed for naturally ventilated schools. Noise is also a problem, so windows are not open as often as it is needed. Usually a pupil is responsible to open the windows between courses. In Greece, an IAQ measuring campaign was performed in 10 existing schools, measuring infiltrations, humidity, temperature, CO2 and VOCs. Results showed poor indoor air quality. Using tracer gases, it was measured the ventilation rate. Results showed that infiltrations had very different values, ranging from 0.1 up to 1.9 air changes/hour depending on the case. When considering infiltration and natural ventilation (opening windows) rates ranged between 1.3 and 11 air changes/hour.

19

Measuring air quality directly is quite difficult. A combination of sensors will be the best solution to monitor IAQ. When it is not possible, CO2 sensors seem to apply as good indicators of occupancy and ventilation rates.

Ventilation with heat recovery is poorly implemented in Mediterranean climates. For summer conditions, cooling recovery system has efficiency around 10% less than heat recovery system. LIMA residential prototype in Barcelona region has a heat recovery unit, with “cold” efficiency value around 50%. Standard use for heat recovery unit could be: winter with heat recovery, spring and fall by‐pass, and summer with cooling recovery (if no active cooling, it may be by‐passed).

Which are the actions towards Indoor Air Quality at Schools?

‐ Step 1: Measure CO2 and establish a “flags” system to improve ventilation rate (when yellow or red colours appear, windows should be opened)

‐ Step 2: Implement a decentralized mechanical ventilation unit with heat recovery (1‐2 units per class)

Night ventilation deals with security issues. Where open windows are the ventilation inlets, this may cause problems when the building is unoccupied at night, especially on the ground floor.

Existing schools have manual shadings that are not working properly, due to both design and use phase’s failures. This leads to around 88 hours of overheating per year, meanwhile retrofitted passive schools count around 247 hours. Currently, overheating problems are reported, as no attention was paid to summer comfort during the design phase of schools.

As new buildings are built with more thermal insulation and improved standards of airtightness, concerns are emerging of an increased risk of overheating. Alongside the key issue of indoor air quality, overheating is a risk that needs to be managed carefully as we move further towards the aim of nZEB and now ranks among greatest concerns that need to be addressed as a priority.

The potential of improving indoor conditions and thus the related pupils’ outcomes, together with the social benefit coming from “energy and environmental education in early ages” are very important and should motivate the different actors. For this reason, the focus should not be only on energy targets, but also on all the additional benefits of having a better learning environment. It is recognised that improving comfort is a need in most of the school buildings, although this is not clearly stated by public authorities.

3. METHODOLOGYFORTHEDEVELOPMENTOFCASESTUDIES

A methodology has been developed in order to have a common framework to support the replication potential to other countries. This methodology is based on:

1. Information of the data collection and the energy audit of each case study, based in main energy audit parameters (location, building use, architectural description of building, annually energy consumptions from invoice information, facilities/equipment description with technical information and outdoors). This information has been collected in the template SCHHOOL_ENERGY DATA_TEMPLATE.

2. Simulation campaign criteria adopted in terms of:

o Main data integrated on dynamic simulation environment4 and analysis

4 The energy performance of the selected school buildings calculated with Energy plus simulation program

20

o Definition of internal conditions of spaces (in terms of type and use, conditioned and non‐conditioned spaces, typical schedule), insulation levels and solar protection, ventilation rates, window ventilation rates, heating equipment efficiency and set point temperatures, etc.

o Existing materials and technologies for renovation in each case study (identified in ZEMedS School Toolkit); a number of measures dealing with the building envelope and energy systems have been taken into account and listed below:

Renovation of the façade;

Renovation of the roof;

Replacement of existing windows;

Installation of external solar protections;

Replacement of existing lighting with LED;

Installation of ventilation system (i) natural, (ii) mechanical without heat recovery, (iii) mechanical with heat recovery;

Change of heating system;

Installation of PV panels

3. Definition of a common cost criteria in order to homogenise cost analysis: investment €/m2 in thermal insulation of envelope and solar protection, roofs; replacement €/m2 of windows, external doors, solar protection, lighting system, heating system and investment €/m2 of PV panels, etc.

The simulation campaign has been set in steps in order to assess the paybacks of deep renovation process implemented in different stages (considered each 4 years). Paybacks are also measured up for renovation process carried out in a unique stage.

The thickness of the insulation together with the windows quality, were examined step wisely, as fundamental variants:

U thermal transmittance (W/m2K) Variant A Variant B Variant C

Walls 0.40 0.30 0.20

Roofs 0.30 0.22 0.15

Windows and external doors 1.80 1.50 1.30‐1.40

Table 1. Transmittances for each variant

The main parameters considered in the simulation campaign of case studies are the following:

Set point temperature for heating/cooling: 21‐22/26ºC (in existing building), 20/26ºC (in renovated building)

Main occupancy: classrooms (0.44 per/m2), offices (0.21 per/m2), corridors (0 per/m2), W.C. (0 per/m2), dining room (1 per/m2)

Schedules: facility schedulers (use of spaces, heating on/off etc.) have been simulated as real as possible in each case study

Mechanical ventilation when occupancy at 6.5 l/s person in renovated building. No mechanical ventilation in existing building.

21

Infiltration rate of 30 m3/h m2 at 50 Pa in existing building (corresponding to old windows) and 6 m3/h m2 at 50 Pa in renovation (class 3 in air permeability classification corresponding to high efficiency sliding window5)

Natural ventilation for opened windows (5 ACH) 1 hour during break time and half an hour during cleaning tasks, in existing building and in renovation when non occupancy

Main thermal bridges considered in building envelope of existing building, as result of no insulation or no continuity of the wall cavity

Considered 1 to 5 l/person day for the demand of DHW (5 l/person day demand is supposed in schools with cooking service)

Environment conditions (nearby buildings, trees, etc.) considered in order to study shadowing of school building

As a design approach, the proposal of energy renovation has been planned as a deep renovations towards ZEMedS nZEB Schools requirements (cited in 1.2). These renovations have been studied by steps and all at once, in order to assess the decreasing of energy consumption and the cost implication.

4. NZEBRENOVATIONMEASURES

4.1. nZEBrenovationmeasures

The following table is a summary of the packages of measures for the case studies.

Name school Location Results (R) Package of measures

Miguel Hernandez School

Catalonia, Spain

result 1

envelope renovation + mechanical ventilation with heat recovery + lighting + PV system covering (heating by natural gas, ventilation, lighting, DHW by electricity (primary school) and natural gas (pre‐school))

result 2

envelope renovation + mechanical ventilation with heat recovery + lighting + gas condensing boiler for heating in primary school + PV system covering (heating by natural gas, ventilation, lighting, DHW by electricity (primary school) and heating and DHW by natural gas (pre‐school)

Sta. Maria d'Avià School

Catalonia, Spain

result 1

envelope renovation + mechanical ventilation with heat recovery + lighting + gas condensing boiler + PV system covering (heating by fuel, ventilation, lighting, DHW by electricity (pre‐school)

result 2

envelope renovation + mechanical ventilation with heat recovery + lighting + biomass boiler + PV system covering (heating by fuel, ventilation, lighting, DHW by electricity (pre‐school)

5 In school buildings, windows are preferably sliding to prevent possible impacts

22

Primary school 13‐33 th

Peristeri, Greece

result 1

envelope renovation + lighting + ventilation with natural ventilation + heating system (boiler)+ PV system covering (heating, lighting, ventilation)

result 2

envelope renovation + lighting + ventilation with mechanical ventilation + heating system (boiler)+ PV system covering (heating, lighting, ventilation)

result 3

envelope renovation + lighting + ventilation with mechanical ventilation with heat recovery + heating system (boiler)+ PV system covering (heating, lighting, ventilation)

Primary school 25 th Peristeri, Greece

result 1

envelope renovation + lighting + ventilation with natural ventilation + heating system (boiler)+ PV system covering (heating, cooling, lighting, ventilation)

result 2

envelope renovation + lighting + ventilation with mechanical ventilation + heating system (boiler)+ PV system covering (heating, cooling, lighting, ventilation)

result 3

envelope renovation + lighting + ventilation with mechanical ventilation with heat recovery + heating system (boiler)+ PV system covering (heating, cooling, lighting, ventilation)

ITC Benincasa Marche, Italy result 1

envelope renovation + mechanical ventilation with heat recovery + lighting + PV system covering (heating by natural gas, cooling, ventilation, lighting, DHW by natural gas)

ITC Einstein Marche, Italy

result 1 envelope renovation + ventilation with natural ventilation + heating system (condensing boiler)+ PV system covering (heating, lighting, ventilation)

result 2

envelope renovation + ventilation with mechanical ventilation + heating system (condensing boiler)+ PV system covering (heating, lighting, ventilation)

result 3

envelope renovation + ventilation with mechanical ventilation with heat recovery + heating system (condensing boiler)+ PV system covering (heating, lighting, ventilation)

Primary school Salvetti

Tuscany, Italy

result 1

envelope renovation + lighting + ventilation with natural ventilation + heating condensing boiler + PV system covering (heating, lighting, ventilation)

result 2

envelope renovation + lighting + ventilation with mechanical ventilation + heating condensing boiler + PV system covering (heating, lighting, ventilation)

result 3

envelope renovation + lighting + ventilation with mechanical ventilation with heat recovery + heating condensing boiler + PV system covering (heating, lighting, ventilation)

ITC Don Milani Tuscany, Italy result 1

envelope renovation + lighting + ventilation with natural ventilation + heating condensing boiler + PV system covering (heating, lighting, ventilation)

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result 2

envelope renovation + lighting + ventilation with mechanical ventilation + heating condensing boiler + PV system covering (heating, lighting, ventilation)

result 3

envelope renovation + lighting + ventilation with mechanical ventilation with heat recovery + heating condensing boiler + PV system covering (heating, lighting, ventilation)

Salamanque Group school

Montpellier, France

result 1

envelope renovation + lighting + mechanical ventilation with heat recovery + PV system covering (heating by natural gas, lighting, ventilation, DHW by electricity)

Bédarieux Group school

Bédarieux, France

result 1 (step 1+ step 2.1)

envelope renovation + heating system (biomass boiler) + PV system covering (lighting, DHW by electricity)

result 2 (step 1+ step 2.2)

envelope renovation + lighting + heating system (biomass boiler) + PV system covering (lighting, DHW by electricity)

Table 2. Packages of energy measures considered in simulation campaign

The packages of measures have been structured in steps in order to study the paybacks each 4 years (more extended information of each measure and steps in 7.1). The energy results of each package renovation (results) are showed in Table 3.

Renovation of the façade

In the cases studied, the current façades consist in:

Brick walls with wall cavity and without insulation material – U wall transmittance (excluding thermal bridges) are around 1 ‐1.5 W/m2K

Others non‐insulated like brick walls, cinder block walls, wooden panel walls, etc. – high values of wall transmittance in more than 1.5 W/m2K

U transmittance of walls has been studied step wisely to reach values of 0.4, 0.3 and 0.2 W/m2K in each case study. External wall insulation system have been considered in all cases (ETICS and ventilated façade) avoiding thermal bridges. The thickness of the insulation (standard expanded polystyrene 0.04 W/mK) is around 70 mm, 100 mm and 160 mm, respectively, for brick walls with wall cavity and without insulation material, and 90 mm, 120 mm and 180 mm for non‐insulated walls.

In some case studies, Greek and Italian examples, additional cool coating products have been applied in facades in order to reduce solar radiation over façade during summer time.

Renovation of the roof

Some of the current roofs of cases studies have already been renovated with U transmittance between 0.80 and 0.40 W/m2K (even 0.20 W/m2K in primary school of Salamanque Group School). For non‐renovated cases U transmittance values are more than 2.5 W/m2K.

The renovation of the roofs has been studied in the project step wisely to reach values of 0.30, 0.22 and 0.15 W/m2K:

For terrace roofs, external roof insulation system including wind/moisture barriers with new tiles (thickness of the insulation ‐ standard expanded polystyrene 0.04 W/mK ‐ are around 120 mm, 170 mm and 250 mm)

24

For pitched roofs with unheated space under cover, insulation system applied internally (thickness of the insulation ‐ standard mineral wool rolls 0.04 W/mK‐ are around 120 mm, 170 mm and 250 mm)

In some case studies, Greek and Italian examples, additional cool coating products have been applied in roofs in order to reduce solar radiation during summer time.

Renovation of ground floor

Renovation on ground floors have not been taken into account in any case because of no energy savings estimated.

Renovation of the windows and external doors

In the current state, most of the case studies have single‐glazed windows with aluminium frames with thermal bridge, U window transmittance of 5.7 W/m2K and old shutter rollers as shading systems. Other cases, in some renovation updates, have double‐glazed windows with aluminium frames with thermal bridges, U = 3.3 W/m2K in average.

The proposal renovations of existing windows are with low‐e double‐glazed windows (air or argon cavity of 16 mm) and frames with thermal break (aluminium and wood frames). Also the correct installation of windows is heavily considered in order to assure low airtightness (on the order of 6 m3/h m2 at 50 Pa for sliding windows class 3, in window classification of air permeability UNE‐EN 12207).

Concerning the solar protection, exterior mobile slats have been considered in replacement of old shutter rollers or inexistent solar protection in order to prevent internal overheating, especially in classrooms.

Replacement of existing lighting

Current T8 fluorescent lamps are proposed to be replaced when necessary with T8 LED tubes in classrooms, offices and corridors in 6.3 W/m2, 10 W/m2 and 4 W/m2, respectively.

Installation of ventilation system

No mechanical ventilation systems exist in typical schools in Mediterranean countries; ventilation is produced by opening windows. However, new school buildings and deep renovations must follow thermal building regulations concerning heating, cooling and ventilation equipment, in order to assure, among others requirements, indoor environmental quality, removing contaminants and reducing internal temperatures in spaces with high level of human occupation.

6.5 l/s person has been considered in the energy simulation campaign of case studies following the Europe tendency rates. In particular, 5 case studies have been simulated in 3 versions of ventilation systems in order to assess energy saving differences: natural, mechanical without heat recovery and mechanical with heat recovery. For the rest cases, only heat recovery system has been considered.

Replacement of heating system

Old natural gas or oil boilers are proposed to be replaced for condensing boilers or biomass boilers, if locally feasible.

In general, DHW is supposed to be poorly used in schools, so no replacements are proposed, except when DHW is supported by the same boiler producing heating.

25

Installation of PV panels

In order to achieve requirement 1 (annual energy balance of non‐renewable energy sources to meet zero), renewable energy needs to be installed to cover heating, cooling, ventilation, DHW and lighting when that energy demands are not supplied by renewable sources.

The cost of the investments are grouped in the next table. In façade and roofs, preparation works and assembling, disassembling and daily amortization of scaffolds are included.

Renovation measures Cost investments

Façade U=0.4 W/m2K: External insulation system (ETICS) with 7 cm EPS (scaffold included)

86‐89 €/m2

In Greece: around: 50 €/m2


96‐94 €/m2

In Greece: around: 60 €/m2


98‐103 €/m2 In Greece: around: 90 €/m2

Ventilated façade (U=0.4 W/m2K) with 6 cm ‐ 9 cm EPS

120 – 130 €/m2 6 cm EPS for brick walls with wall cavity and 9 cm for wood panel (Group School Salamanque)

Ventilated façade (U=0.3 W/m2K) with 9 cm ‐ 12 cm EPS


Ventilated façade (U=0.2 W/m2K) with 15 cm ‐18 cm EPS


Roof (U=0.3 W/m2K): Internal insulation system with 12 cm MW

27 €/m2


31 €/m2


36 €/m2

Roof : External insulation system (3cm roof tiles with cool material coating and 7.5cm EPS attached)

50 €/m2

Roof: External insulation system (3cm roof tiles with cool material coating and 10.5cm EPS attached)

65 €/m2

Roof: External insulation system (3cm roof tiles with cool material coating and 14.5cm EPS attached)

70 €/m2

Window: low‐e double‐glazed, air cavity of 16 mm, aluminium frames with thermal break

395 €/m2

Window: low‐e double‐glazed, argon cavity of 16 mm, aluminium frames with thermal break

400 – 480 €/m2

Window: low‐e double‐glazed, argon cavity of 16 mm, wood frames with thermal break

425 – 435 €/m2 In France: around 665 €/m2

solar protection with mobile slats 162 €/m2

LED technology efficiency 66lm/W 1462 – 1500 €/classroom 55 m2

26

Mechanical ventilation without heat recovery 35 €/m2 In Greece: around 20 €/m2

Mechanical ventilation with heat recovery 45 – 55 €/m2 In Greece: around 25 €/m2

PV panels 1.5 €/Wp

27

5. ENERGYRESULTSANDPAYBACKS

The packages of energy efficiency measures in Table 2, implemented by simulation campaign, concern envelope renovation, heating system replacement, ventilation system installation, lighting system replacement, and renewable energy production (photovoltaic) in order to achieve nearly zero energy schools (considered balance 0).

In the following table, resulting values (RES production, final energy consumption in heating, cooling, ventilation and lighting, final energy savings and paybacks) after implementation of the packages in deep renovation processes in case studies (column “Results” represent each energy package of Table 2):

Existing building (simulation values)

Building renovation (simulation values)

School n

ame

Area (m

2)

Total final energy

(kWh/m2) (heating, cooling,

ventilation, lighting and

DHW)

Results

Final energy (kWh/m2 y) in heating, cooling, ventilation and

lighting

Ave

rage

in total FE (kWh/m

2)

Total final energy

6saving %

RES production (kWp) / (kWh/m2 y)

surface PV panels

Paybacks ‐ all at once (ye

ars)

Energy efficiency measures

Envelope renovation

Ventilation System

installation

Ligh

ting system

replacement

Heating system

replacement

Natural gas or oil

Electricity

Total

Var A

7

Var B

8

Var C

9

Var A

Var B

Var C

Miguel H

ernandez School

1147 81 35 116 1 23 21 20 41 0,64

14/16

76 m2 PV

13/15

70 m2 PV

12/14

65 m2 PV

23‐24

yes MVHR LED no

1147 81 35 116 2 20 18 17 38 0,67

12/14

65 m2 PV

11/13

59 m2 PV

11/13

59 m2 PV

24‐25

yes MVHR LEDgas

condensing boiler

Sta. M

aria d'Avià School

1366 90 33 123 1 32 25 21 51 0,59

20/22

108 m2 PV

17/19

92 m2 PV

16/18

86 m2 PV

22 yes MVHR LEDgas

condensing boiler

1366 90 33 123 2 35 27 23 53 0,57

9/10

49 m2 PV

9/10

49 m2 PV

9/10

49 m2 PV

27 yes MVHR LEDbiomass boiler

Primary

school 1

3‐

33th 2005 38 10 48 1 26 25 23 27 0,44

22/17

119 m2 PV

21/16

113 m2 PV

20/16

108 m2 PV

35‐38

yes NV LEDgas

condensing boiler

6 In this document, total final energy refers to the final energy in heating, cooling, ventilation, lighting and DHW.

7 Var A refers to the envelope transmittances: Ufacade=0.4, Uroof=0.3, Uglass=1.64, Uf=2.2 (W/m2K)

8 Var B refers to the envelope transmittances: Ufacade=0.3, Uroof=0.22, Uglass=1.34, Uf=2.2 (W/m2K)

9 Var C refers to the envelope transmittances: Ufacade=0.2, Uroof=0.15, Uglass=1.34, Uf=1.8 (W/m2K)

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Building renovation (simulation values) School n

ame

Area (m

2)

Total final energy



DHW)

Results


lighting

Ave

rage

in total FE (kWh/m

2)

Total final energy

6saving %


surface PV panels


ars)


Envelope renovation

Ventilation System

installation

Ligh

ting system

replacement

Heating system

replacement

Natural gas or oil

Electricity

Total

Var A

7

Var B

8

Var C

9

Var A

Var B

Var C

2005 38 10 48 2 26 26 25 27 0,43

20/16

108 m2 PV

20/16

108 m2 PV

20/16

108 m2 PV

36‐40

yes MV LEDgas

condensing boiler

2005 38 10 48 3 17 15 14 17 0,64

15/12

81 m2 PV

13/10

70 m2 PV

12/9

65 m2 PV

33‐36

yes MVHR LEDgas

condensing boiler

Primary school 2

5th

1030 21 23 44 1 24 22 21 29 0,33

9/13

49 m2 PV

8/12

43 m2 PV

8/12

43 m2 PV

39‐41

yes NV LEDgas

condensing boiler

1030 21 23 44 2 33 31 29 38 0,14

11/16

59 m2 PV

10/15

54 m2 PV

10/15

54 m2 PV

52‐50

yes MV LEDgas

condensing boiler

1030 21 23 44 3 19 17 16 24 0,45

7/10

38 m2 PV

7/10

38 m2 PV

6/9

32 m2 PV

36‐38

yes MVHR LEDgas

condensing boiler

ITC Benincasa

4942 117 27 144 1 25 22 20 54 0,63

109/32

589 m2 PV

102/30

551 m2 PV

98/28

529 m2 PV

22‐23

yes

MVHR

LED no

ITC Einstein

2998 158 11 169 1 66 65 64 82 0,54

83/38

448 m2 PV

81/37

437 m2 PV

81/37

437 m2 PV

22‐23

yes NV no gas

condensing boiler

2998 158 11 169 2 105 104 104 121 0,32

124/57

670 m2 PV

122/56

659 m2 PV

122/56

659 m2 PV

36‐37

yes MV no gas

condensing boiler

2998 158 11 169 3 75 74 73 91 0,49

92/42

497 m2 PV

92/42

497 m2 PV

90/41

486 m2 PV

26‐27

yes MVHR no gas

condensing boiler

Primary school Salve

tti 2300 97 4 101 1 27 24 22 33 0,68

27/15

146 m2 PV

23/13

124 m2 PV

21/12

113 m2 PV

29‐30

yes NV LEDgas

condensing boiler

2300 97 4 101 2 57 55 54 64 0,37

55/32

297 m2 PV

53/30

286 m2 PV

51/29

275 m2 PV

46‐47

yes MV LEDgas

condensing boiler

2300 97 4 101 3 35 33 31 41 0,59

34/20

183 m2 PV

32/18

172 m2 PV

30/17

162 m2 PV

35‐36

yes MVHR LEDgas

condensing boiler

29


Building renovation (simulation values) School n

ame

Area (m

2)

Total final energy



DHW)

Results


lighting

Ave

rage

in total FE (kWh/m

2)

Total final energy

6saving %


surface PV panels


ars)


Envelope renovation

Ventilation System

installation

Ligh

ting system

replacement

Heating system

replacement

Natural gas or oil

Electricity

Total

Var A

7

Var B

8

Var C

9

Var A

Var B

Var C

ITC Don M

ilani

1265 113 8 121 1 51 51 51 55 0,55

29/30

157 m2 PV

panel

29/30

157 m2 PV

panel

29/30

157 m2 PV

panel

34‐36

yes NV LEDgas

condensing boiler

1265 113 8 121 2 59 59 59 63 0,48

33/34

178 m2 PV

panel

33/34

178 m2 PV

panel

33/34

178 m2 PV

panel

39‐41

yes MV LEDgas

condensing boiler

1265 113 8 121 3 51 49 48 53 0,56

28/29

151 m2 PV

panel

28/29

151 m2 PV

panel

28/29

151 m2 PV

panel

37‐38

yes MVHR LEDgas

condensing boiler

Salaman

que

Group school

2303 85 15 100 1 45 44 43 56 0,44

45/30

243 m2 PV

45/30

243 m2 PV

45/30

243 m2 PV

28‐29

yes

MVHR LED no

Bédarieux Group school

3445 107 28 135 1 38 36 33 51 0,62

49/9

265 m2 PV

49/9

265 m2 PV

49/9

265 m2 PV

20‐21

yes no no biomass boiler

3445 107 28 135 2 34 31 29 46 0,77

32/6

173 m2 PV

32/6

173 m2 PV

32/6

173 m2 PV

23‐24

yes no LEDbiomass boiler

Table 3. Results of the implementation of energy measures to achieve nearly zero energy schools (m2 refers to conditioned

area except for PV panels)

According to each result, the values for var A, var B and var C don’t change significantly; only cases with low compactness (like Sta. Maria d'Avià School) or high percentage of window surface are sensitive to an insulation increase of the envelope (from var A to var C). Then, globally speaking variant A is appropriate for reducing energy demand in most of the cases.

Final energy kWh/m2

(in heating, cooling, ventilation and lighting)

Current building

After renovation

% savings

Heating after renovation (gas or oil) kWh/m2)

Miguel Hernandez School ‐result 1 89 22 64% 13

Miguel Hernandez School ‐result 2 89 19 67% 10

Sta. Maria d'Avià School ‐result 1 100 26 59% 17

Sta. Maria d'Avià School ‐result 2 100 28 57% 20

30

Primary school 13‐33 th‐result 1 46 25 44% 22



Primary school 25 th‐result 1 37 22 33% 17



ITC Benincasa‐result 1 112 22 63% 10

ITC Einstein‐result 1 163 65 54% 60



Primary school Salvetti‐result 1 93 24 68% 24



ITC Don Milani‐result 1 117 59 55% 49



Group school Salamanque‐result 1 98 44 44% 35

Group school Bédarieux ‐result 1 113 36 62% 22

Group school Bédarieux ‐result 2 113 31 77% 24

Table 4. Average of final energy in heating, cooling, ventilation and lighting before and after renovation (simulation values)

Figure 2. Final energy consumption in (heating, cooling, ventilation and lighting) in current situation and after renovation

31

Figure 3. Kg of CO2/m2 y during the use of case studies

To accomplish with requirement 2 [CFE ≤ 25 kWh/m conditioned area².year in heating, cooling, ventilation and lighting] the following is observed:

Results depend strongly on the current situation of case studies (see Table 4); in general terms, school buildings with less than 100 kWh/m2 y in gas or oil consumption reaches values around 25 kWh/m2.

Results related to ventilation system; in the 5 case studies in which 3 versions of ventilation systems have been simulated (Primary school 13‐33 th, Primary school 25 th, ITC Einstein, Primary

school Salvetti and ITC Don Milani), mechanical ventilation with no heat recovering appears not be an energy and costly efficiency measure compared with natural ventilation or mechanical ventilation with heat recovering, even in Mediterranean climates as higher energy consumption in current schools is in heating.

The 56% are the energy savings in heating, cooling, ventilation and lighting for the case studies accomplishing the requirement 2.

1‐floor buildings don’t have an improvement potential as buildings with higher compactness, e.g. ITC Don Milani.

Furthermore, energy strategies such as the reduction of the internal loads with the improvement of lighting with LED technology can contribute to less than 25kWh/m2 in FE. The average of lighting consumption in current case studies is 9 kWh/m2 y, and with LED lighting can reach 5 kWh/m2 y.

The case of Salamanque Group School (with 2 buildings and one of them 1‐floor building), consumes in heating, 85 kWh/m2 y in current situation and 35 kWh/m2 after proposed renovations. Its current envelope compounded mainly by wood panels makes a special case to be studied deeply.

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It is highly recommended to produce fresh air by natural ventilation with dynamic systems in terms of energy saving, but it will depend of each case if natural ventilation is feasible in front of forced ventilation. In general terms, the requirements about interior air quality (requirement 3) are guaranteed with mechanical ventilation more easily than with natural ventilation, especially in renovation works.

In relation to avoid overheating during summer time, mobile horizontal slats have been suggested as a general rule in classrooms, but there have been some cases (e.g. Group school Salamanque, ITC Benincasa) which ventilated façades and roofs have been an option in some facades. In other cases, relatively little spaces that have some appliances installed have given more hours than 40; special attention in ventilation rate is recommended to evacuate heat loads in these cases.

Following requirement 1, in which primary energy yearly (heating, cooling, ventilation, lighting and DHW) is produced by renewable energies, next values are the prediction of RES production for the cases accomplishing requirement 2:

Final energy kWh/m2(in heating, cooling, ventilation

and lighting)

Current building

After renovation

RES production kWh/m2 y

% RES in energy balance

Miguel Hernandez School ‐result 1 89 22 15 70%

Miguel Hernandez School ‐result 2 89 19 14 73%

Sta. Maria d'Avià School ‐result 1 100 26 20 76%

Sta. Maria d'Avià School ‐result 2 100 28 10 35%

Primary school 13‐33 th‐result 1 46 25 17 66%



Primary school 25 th‐result 1 37 22 13 56%

Primary school 25 th‐result 3 37 17 10 55%

ITC Benincasa‐result 1 112 22 30 134%

Primary school Salvetti‐result 1 93 24 13 55%

Table 5. Percentage of predicted RES

The average of RES production is 62% of the final energy consumption in heating, cooling, vent. and lighting. In the case of Benincasa, high production of DHW in the gyms raises the RES production in comparison to others cases. For Avià case study, 76% (heating by gas condensing boiler) versus 35% (heating produced by biomass).

In terms of payback periods10, deep renovation processes implemented by different stages (considered each 4 years) take more than 50 years in total in all case studies, otherwise, for deep renovation processes carried out in a unique stage, not less than 20 years, but around 25 – 35 years (see Table 3).

Nevertheless, it has to be highlighted that case studies have been developed in order to be conservative in terms of energy saving final results, and have not considered two steps of the nZEB Energy Steps as presented in the toolkits: the use and management of the measures, and the building management systems. The reason is that energy systems of case studies have been simulated by ideal systems and seasonal average performances and with some just elementary timer controls. This means that the

10 The calculations are based on a constant average yearly energy prices increases and inflation rates obtained from the last 10 years in each country (source Eurostat).

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resulting simulations used for case studies, are conservative, giving a "worse case" results, while literature shows are highly cost‐effective e.g. a good use and simple energy management actions can result in average energy savings of around 10% (even though savings can differ widely depending on the status quo).

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6. CONCLUSIONS

The ZEMeds project intents to elucidate the relationship between nearly zero‐energy and cost‐optimal measures and to develop an argumentation on how to ensure a smooth transition from current MED schools to nearly zero energy school buildings.

Following a deep renovation strategy, different packages of measures have been examined dealing with the building envelope and energy systems. In this context, the results are presented with case studies of school buildings that have been analysed in terms of the energy efficiency and cost optimality so as to define a detailed renovation action plan.

• A typical Mediterranean school built in the period 60‐80’s may consume around 110 kWh/m2/y (final energy), count with many overheating hours, has glare problems and inefficient ventilation;

• With the suggested measures, classrooms used during summertime reduce overheating hours to less than 40h;

• There is a lack of information of the costs in maintenance and replacements concerning the existing building;

• The payback periods are not less than 20 years for deep renovation works carried out in a unique stage; for work plans in different stages it takes more than 50 years

• Although improving building efficiency is often profitable, investments are hindered by barriers In general in any case, actual NZEB renovation requires the implementation for the "deep renovation" measures that are necessary for achieving the almost zero consumption level but also economically not sustainable. This lead to the final effect that NZEB renovation usually requires very high ROI periods, and this seems to be quite critical for the actual implementation of the NZEB plan and measures. Setting the priorities for building renovations will be based on different needs (safety, maintenance, spatial requirements, energy savings, etc.) and will heavily depend on the budget availability and the existing funding channels. Nowadays, the economic crisis in most of Mediterranean countries has led to very reduced self‐financing capacity, being the budgets allocated to cover only urgent needs and significantly reducing the capacities of municipalities and regional administrations. This fact highlights how overlooked are other funding opportunities, such as the use of ERDF funds. Specifically, it is expected that ‐especially for school manager with a wide school building heritage‐ authorities will prefer to implement few cost effective measures in more schools than the whole NZEB plan (with also high ROI measures) in just one or few schools. It is important to consider that this choice can be reasonable also in a global climate change perspective, as with the same funding, probably a Public Authority can achieve higher energy saving and CO2 reduction implementing more cost‐effective measures in more schools, than investing for having just one of few NZEB buildings. A foremost recommendation that can be given is to “carefully evaluate the project design, viability and expected results”. Precisely on this topic the ZEMedS project has developed and extensive set of tools and resources that will greatly help administrators to carry out this preliminary evaluation. Furthermore, the consortium strongly recommends that regional energy agencies or other regional related organisms become trained to provide practical and detailed advice to any interested parties. Considering the previous points and the existing budgetary constraints throughout Europe and especially in the Mediterranean Region the following recommendations should be considered:

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a. Prioritize renovations in the least energy performing buildings and infrastructures.

b. Prioritize NZEB‐like renovations in buildings that already have a normal renovation plan.

c. When doing the calculation of the payback periods do not use the full cost of the renovation action but rather calculate the difference in cost between a standard renovation and a NZBE renovation (on very rough terms this is normally between 15% to 25%). For example if a school is well below the temperature comfort standards it may decide to change the insolation in a few given areas. The cheapest solution which matches the legal construction requirements may be as low as 24€m2 whilst a system providing a much higher energy performance could be installed for 34€m2, thus the real cost of the additional investment required for energy performance would be 10€ m2, and any payback calculation should be carried out using these differences in figures.

It’s not always about the money; energy efficiency, suitable education facilities and the conservation of the environment are not costs but investments that have to be done for the wellbeing of future generations.

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7. ANNEXES

7.1. nZEBrenovationmeasuresforcasestudies

Miguel Hernandez School nZEB renovation measures:

Variant A Variant B Variant C

Step 1

Uwindows and doors

1.8

6mm/16mm(AIR)/6mm le (<0.04) aluminum window frame (with thermal break) . Ug=1.64 Uf= 2.2

1.5

6mm/16mm(ARGO)/6mm le (<0.04) aluminum window frame (with thermal break) . Ug=1.34 Uf= 2.2

1.4

6mm/16mm(ARGO)/6mm le (<0.04) wooden window frame. Ug=1.34 Uf= 1.8

Solar protection

Exterior mobile slats Exterior mobile slats Exterior mobile slats

Mechanical Ventilation

Ventilation system with heat recovery (control when occupancy) 6.5 l/s person, 70% heat recovery

Step 2

Uroof 0.30Internal insulation system (12 cm of MW Mineral Wool rolls)

0.22Internal insulation system (17 cm of MW Mineral Wool rolls)

0.15 Internal insulation system (25 cm of MW Mineral Wool rolls)

Uwall 0.4

External insulation system (7 cm of EPS Expanded Polystyrene (standard))

0.3

External insulation system (10 cm of EPS) Expanded Polystyrene (standard))

0.2

External insulation system (17 cm of EPS Expanded Polystyrene (standard))

Ugroundfloor

current (U groundfloor 1.4)

Step 3.1

Lighting replacing T8 tubes for LED tubes in classrooms 6.3 W/m2

Heating system & DHW in primary school and pre‐school

current system: gas boiler for heating and electric heater for DHW in pre‐school, efficiency 0.81

current system: gas boiler for heating and DHW in pre‐school, efficiency 0.85

Cooling system no cooling system

PV system 27 kWp / 32 kWh/m2 (conditioned area)

Step 3.2


Heating system in primary school

gas condensing boiler (efficiency 1.05) in primary school for heatingcurrent electric heater for DHW

Heating system & DHW in pre‐school

current system (gas boiler for heating and DHW, 0.85)


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PV system 26 kWp , 31 kWh/m2

m2 (conditioned area)

Miguel Hernandez School renovation under current Spanish regulation:

Current regulation Technical Building Code (update 2013), Thermal Building Regulations (Royal Decree 1027/2007) and Catalan Decree 21/2006 and Decree 111/2009

Uwindows and doors

Uw = 3.3 // 6mm/16mm/6mm metal window frame. Ug=2.6 Uf= 4.7

Solar protection Exterior mobile slats


12.5 l/per sec (mechanical ventilation, 70% heat recovery)

Uroof 0.41 (Internal insulation system (8 cm of MW Mineral Wool rolls)

Uwall 0.7 (External insulation system, 3 cm of EPS Expanded Polystyrene (standard))

Ugroundfloor current (U groundfloor 1.4)

DHW current

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Sta. Maria Avià School nZEB renovation measures:


Step 1

Uwindows and doors

1.8

6mm/16mm(AIR)/6mm le (<0.04) aluminum window frame (with thermal break) . Ug=1.64 Uf= 2.2

1.5

6mm/16mm(ARGO)/6mm le (<0.04) aluminum window frame (with thermal break) . Ug=1.34 Uf= 2.2

1.4


Solar protection

Exterior mobile slats Exterior mobile slats Exterior mobile slats



Step 2

Uroof 0.30Internal insulation system (10 cm of MW Mineral Wool rolls)

0.22Internal insulation system (14 cm of MW Mineral Wool rolls)

0.15 Internal insulation system (21 cm of MW Mineral Wool rolls)

Uwall 0.4

External insulation system (6‐8 cm of EPS Expanded Polystyrene (standard))

0.3

External insulation system (10 ‐12 cm of EPS) Expanded Polystyrene (standard))

0.2

External insulation system (16‐18 cm of EPS Expanded Polystyrene (standard))


Step 3.1

Ligthing classrooms 6.3 W/m2. offices 10 W/m2. corridors 4.2 W/m2. LED tubes 10 W, 20 W, 25 W

Heating system

Condensing boiler (efficiency 1,05)

Cooling system

current (library)

PV system 20kWp / 22 kWh/m2 17 kWp / 19 kWh/m2 16 kWp / 18 kWh/m2

Step 3.2

Ligthing classrooms 6.3 W/m2, offices 10 W/m2, corridors 4.2 W/m2. LED tubes 10 W, 20 W, 25 W

Heating system & DHW

Biomass boiler, 320 kW / (>0,92)

Cooling system

current (library)

PV system 9 kWp / 10 kWh/m2 9 kWp / 10 kWh/m2 9 kWp / 10 kWh/m2

m2 (conditioned area)

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Sta. Maria Avià School renovation under current Spanish regulation:

Current regulation Technical Building Code (update 2013), Thermal Building Regulations (Royal Decree 1027/2007) and Catalan Decree 21/2006 and Decree 111/2009

Uwindows and doors

Uw = 3.3 // 6mm/16mm/6mm metal window frame with thermal break. Ug=2.6 Uf= 4.7

Solar protection Exterior mobile slats


12.5 l/per sec with heat recovery

Uroof 0.41 (Internal insulation system (8 cm of MW Mineral Wool rolls)

Uwall 0.7 (including thermal bridge) (External insulation system, 5 cm of EPS Expanded Polystyrene (standard))


DHW current

40

13th‐33th Primary School nZEB renovation measures:


Step 1

Uwindows andexterior doors

1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air)and aluminum frame (with thermal break) .Ug=1.6 Uf= 2.2Variant B: low‐e double glazing,16mm(argon) and aluminum frame (withthermal break) . Ug=1.3 Uf= 2.2Variant C: low‐e double glazing,16mm(argon) and aluminum frame . Ug=1.3Uf= 2.2

Solar protection Interior Curtains ‐

Uroof 0.3 0.22 0.15

Variant A: 3cm roof tiles with cool materialcoating and 7.5cm EPS attachedVariant B: 3cm roof tiles with cool materialcoating and 10.5cm EPS attachedVariant C 3cm roof tiles with cool materialcoating and 145m EPS attached

Uwall 0.4 0.3 0.2

Variant A: External wall insulation 6cm EPS &plaster with cool coatingVariant B: External wall insulation 10cm EPS& plaster with cool coatingVariant C: External wall insulation 12cm EPS& plaster with cool coating

Ugroundfloor current ‐

Step 2 Lighting led lamps efficiency 66lm/W and dimmer

Step 2.1

Natural Ventilation Windows open sceanrio ( 0,008 m3/sec/person)

Heating system Boiler (COP 2)


PV system 246m2 PV panels

Step 2.2

Mechanical Ventilation Ventilation systems without heat recovery (control when occupancy) 6.5 l/s person




Step 2.3

Mechanical Ventilation Ventilation systems without heat recovery (control when occupancy) 6.5 l/s person, 70% heat recovery




13th‐33th Primary School renovation under current Greek regulation:

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Schedule

Hours 8

Days 5

Months 8 (October till May)

Envelope

U wall 0,4

U roof 0,4

U floor 0,75

Internal Gains, Ventilation and Set points

Ventilation 11m3/h/m2

Lighting 9,6 W/m2

Equipment 5 W/m2

Heating / Cooling 20˚C / 26˚C

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25th Primary School & Kindergarten nZEB renovation measures:


Step 1


1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air) and aluminum frame (with thermal break) . Ug=1.6 Uf= 2.2Variant B: low‐e double glazing, 16mm(argon) and aluminum frame (with thermal break) . Ug=1.3 Uf= 2.2Variant C: low‐e double glazing, 16mm(argon) and aluminum frame . Ug=1.3 Uf= 2.2


Uroof 0.3 0.22 0.15

Variant A: 3cm roof tiles with cool material coating and 7.5cm EPS attached Variant B: 3cm roof tiles with cool material coating and 10.5cm EPS attached Variant C 3cm roof tiles with cool material coating and 145m EPS attached

Uwall 0.4 0.3 0.2

Variant A: External wall insulation 6cm EPS & plaster with cool coating Variant B: External wall insulation 10cm EPS & plaster with cool coating Variant C: External wall insulation 12cm EPS & plaster with cool coating


Step 2 Lighting led lamps efficiency 66lm/W and dimmer

Step 2.1

Natural Ventilation Windows open scenario (0,008 m3/sec/person)


Cooling system current cooling system

PV system 9 kWh/m2/ 32 m2 PV panels

Step 2.2





Step 2.3





25th Primary School & Kindergarten renovation under current Greek regulation:

43

Schedule

Hours 8

Days 5

Months 8 (October till May)

Envelope

U wall 0,4

U roof 0,4

U floor 0,75

Internal Gains, Ventilation and Set points

Ventilation 11m3/h/m2

Lighting 9,6 W/m2

Equipment 5 W/m2

Heating / Cooling 20˚C / 26˚C

44

ITC Benincasa nZEB renovation measures:


Step 1

Uwindows and doors

1.8

6mm/16mm(AIR)/6mm le (<0.04) aluminium window frame (with thermal break) . Ug=1.64 Uf= 2.2

1.5

6mm/16mm(ARGO)/6mm le (<0.04) aluminium window frame (with thermal break) . Ug=1.34 Uf= 2.2

1.4


Solar protection

Mobile slats Mobile slats Mobile slats



Step 2

Uroof current (U roof 0.42)

Uwall 0.4 Ventilated facade with insulation system

0.3 Ventilated facade with insulation system

0.2 Ventilated facade with insulation system

Ugroundfloor

current (U groundfloor 0.9)

Step3


Heating system & DHW

current

Cooling system

current

PV system 69 kWp / 20 kWh/m2 / 588 m2 PV panels

66 kWp / 19 kWh/m2 /551 m2 PV panels

62 kWp / 18 kWh/m2 / 529 m2 PV panels

ITC Benincasa renovation under current Greek regulation:

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Current regulation D.Lgs. 311/06

Uwindows and doors Window Uw=2.2; Ug=1.9

Solar protection Mobile slats


no mechanical ventilation

Uroof 0.29 (interior insulation system)

Uwall 0.36 (exterior insulation system)

Ugroundfloor Ugroundfloor= 0.36 (interior insulation system)

PV system 22 kWp / 6 kWh/m2 (50% of expected energy consumption for DHW, heating, cooling)

46

ITC Einstein nZEB renovation measures:


Step 1

Uwindows and exterior doors

1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air) and wooden frame (with thermal break) . Ug=1.6 Uf= 2.2 Variant B: low‐e double glazing, 16mm(argon) and wooden frame (with thermal break) . Ug=1.3 Uf= 2.2Variant C: low‐e double glazing, 16mm(argon) and wooden frame . Ug=1.3 Uf= 2.2


Uroof 0.3 0.22 0.15

Variant A: 3cm roof tiles with cool material coating and 4cm EPS attached Variant B: 3cm roof tiles with cool material coating and 7cm EPS attached Variant C 3cm roof tiles with cool material coating and 14cm EPS attached

Uwall 0.4 0.3 0.2



Step 2.1

Natural Ventilation Windows open sceanrio ( 0,008 m3/sec/person)

Heating system Condensing boilers



Step 2.2





Step 2.3





47

ITC Salvetti nZEB renovation measures:


Step 1


1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air) and aluminium frame (with thermal break) . Ug=1.6 Uf= 2.2Variant B: low‐e double glazing, 16mm(argon) and aluminium frame (with thermal break) . Ug=1.3 Uf= 2.2Variant C: low‐e double glazing, 16mm(argon) and aluminium frame . Ug=1.3 Uf= 2.2


Uroof 0.3 0.22 0.15

Variant A: 3cm roof tiles with cool material coating and 10cm EPS attached Variant B: 3cm roof tiles with cool material coating and 15cm EPS attached Variant C 3cm roof tiles with cool material coating and 20cm EPS attached

Uwall 0.4 0.3 0.2



Step 2 Lighting led lamps efficiency 66lm/W

Step 2.1

Natural Ventilation Windows open scenario ( 0,008 m3/sec/person)

Heating system Gas condensing boiler (COP 1.05)


PV system 146‐113m2 PV panels

Step 2.2





Step 2.3





48

Don Milani Primary School nZEB renovation measures:


Step 1


1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air) andaluminum frame (with thermal break) . Ug=1.6 Uf=2.2 Variant B: low‐e double glazing, 16mm (argon) andaluminum frame (with thermal break) . Ug=1.3 Uf=2.2 Variant C: low‐e double glazing, 16mm (argon) andaluminum frame (with thermal break) . Ug=1.3 Uf=2.2


Uroof 0.3 0.22 0.15

Variant A: 3cm roof tiles with cool material coatingand 4cm EPS attachedVariant B: 3cm roof tiles with cool material coatingand 7cm EPS attachedVariant C 3cm roof tiles with cool material coatingand 14cm EPS attached

Uwall 0.4 0.3 0.2

Variant A: External wall insulation 6cm EPS & plasterwith cool coatingVariant B: External wall insulation 10cm EPS & plasterwith cool coatingVariant C: External wall insulation 14cm EPS & plasterwith cool coating


Step 2 Lighting led lamps efficiency 66lm/W

Step 2.1

Natural Ventilation Windows open scenario ( 0,008 m3/sec/person)

Heating system Gas condensing boiler (efficiency 1.05)



Step 2.2





Step 2.3





49

Salamanque Group School nZEB renovation measures:


Step 1


1.8 1.5 1.4

Decreasing % window area on classrooms inprimary school and pre‐school Replacement of existing 20 years old windowsand exterior doors for:Variant A: low‐e double glazing, 16mm (air) andaluminum frame (with thermal break). Ug=1.6 Uf=2.2 Variant B: low‐e double glazing, 16mm (argon)and aluminum frame (with thermal break). Ug=1.3Uf= 2.2Variant C: low‐e double glazing, 16mm (argon)and wooden frame. Ug=1.3 Uf= 1.8

Solar protection current ‐

Uroof and Ufloor incontact with exteriorair

0.3 0.22 0.15

Ventilated roof with insulation system in pre‐school roofPaving concrete slabs in primary roof

Uwall 0.4 0.3 0.2 Ventilated facade with insulation system (exceptthe north façade in primary school and therenovated façade in pre‐school)


Step 2 Lighting replacing T8 tubes for T5 tubes in classrooms of pre‐school with 6.3 W/m2 (no saving in electricity consumption when replacing lighting in primary school)

Step 3

Mechanical ventilation

mechanical ventilation 6,5l/per sec in classrooms and offices

Heating system current

DHW current


PV system 42 kWp / 28 kWh/m2

50

Langevin Wallon School Group nZEB renovation measures:


Step 1

Uwindows and exterior doors

1.8 1.5 1.4

Replacement of existing single glazing for:Variant A: low‐e double glazing, 16mm(air) and aluminium frame (with thermal break) . Ug=1.6 Uf= 2.2Variant B: low‐e double glazing, 16mm(argon) and aluminium frame (with thermal break) . Ug=1.3 Uf= 2.2Variant C: low‐e double glazing, 16mm(argon) and wooden frame . Ug=1.3 Uf= 1.8

Solar protection current ‐

Uroof and Ufloor in contact with exterior air

0.3 (for gym current U=0.27)

0.22 0.15

LW1 : Ventilated roof with insulation system LW2 (restaurant): Ventilated roof with insulation system Pre‐school : Ventilated roof with insulation system Gym (except toilets): Interior insulation system

Uwall 0.4 0.3 0.2 LW1, pre‐school and gym: External insulation system LW2: Ventilated facade with insulation system


Step 2.1

Lighting current

Mechanical Ventilation no ventilation systems

Heating system & DHW Biomass boiler, 500 kW / (>0.92)



Step 2.2

Lighting classrooms 6.3 W/m2, offices 10 W/m2, corridors 4.2 W/m2 with LED tubes 10 W, 20 W, 25 W

Mechanical Ventilation no ventilation systems

Heating system & DHW Biomass boiler, 500 kW / (>0.92)



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