energy saving measures in refurbishment of dwellings in
TRANSCRIPT
Dušan Petráš
Energy Saving Measures in Refurbishment
of Dwellings in Slovakia
Slovak University of Technology in Bratislava, Faculty of Civil Engineering, Slovakia
Energy Auditing and Certification of Buildings
The total energy system
Production Distribution Consumption
Industry
Buildings
ENergy CONservation (ENCON) :
is saving energy with
an economic and environmental profit !
Energy Conservation ?
1.
2.
3.
Energy Conservation Project
Objectives :
Evaluation of the ENCON potential
Implementation in order to achieve profitable energy
savings
Achievement of calculated energy saving potential and
keeping it permanently on the right level
Detailed Auditing with guarantee
Simplified
Auditing
Operation
Implementation
Scanning
Project
Identification
ENCON Potential USD, kWh/year
Profit
Training
Maintenance
Project
Management
Energy
Monitoring
Business Planning
The ENCON Process
What is influencing the
Energy Conservation Potential ?
Electrical
systems
Operation /
user pattern
HVAC
systems
Building
envelope
ENCON Potential
Building:
ENSI® Head Office, Oslo
Project no:
10130
Heated area:
2.300 m²
ENCON measures Investment Net saving Payback NPVQ*
[USD] [kWh/yr] [USD/yr] [year]
1. Energy efficient showers 400 2 300 200 2,0 2,51
2. O&M manuals / Energy managem. 15 000 81 000 7 100 2,1 2,32
3. Sealing of windows 10 000 80 000 8 000 1,3 2,28
4. Insulation of attic 12 500 17 800 1 800 6,9 0,79
5. Insulation of pipes, etc. 9 500 17 700 1 800 5,3 0,73
6. Balancing and thermostatic valves 22 500 53 800 5 400 4,2 0,69
7. Heat recovery, ventilation system 25 000 37 000 3 200 7,8 0,17
8. Automatic control 20 000 38 000 3 300 6,1 0,16
Total ENCON measures 114 900 327 600 30 800 3,7
*) Real interest rate 7%
To promote the improvement of the energy performance of
buildings through cost effective measures (new and existing
buildings)
The Directive require the following to be introduced:
Methodology for calculating the energy performance of buildings (EN ISO
13790);
Application of performance standards for new and existing buildings;
Certification schemes for buildings;
Regular inspection and assessment of boilers, heating systems and
air conditioning systems
Objective:
To prepare “Certificate” and identify “Cost effective
measures” Energy Auditing (Directive 2006/32 EC, EN 15217)
EU Directive on the Energy Performance of Buildings
Energy Performance and Energy Requirements
Energy Performance: overall indicator EP = weighted sum of net delivered
energy per energy carrier (per m2 conditioned area). EP may represent:
Primary energy;
CO2 emissions;
Net delivered energy weighted by any other nationally defined
parameters
EP may be completed by other indications, defined by national bodies. Energy Requirements: minimum level of EP to be achieved.
To ways of expressing the energy requirements EPr:
1. Overall EP requirement
2. Specific requirements:
Energy use for heating, ventilation, DHW, cooling and lighting
Energy need for heating, ventilation, DHW, cooling
Characteristics of the building itself or its technical building systems
considered as a whole
Characteristics of the building itself or its technical building systems
components
New buildings and major renovations: one overall EP requirement shall be
included
Types of Energy Rating
Name Input data Purpose
Use Climate Building
Calculated Design Standard Standard Design Building permit,
Certificate under
condition
Standard Standard Standard Actual Energy Certificate,
compliance with
building regulations
Tailored Actual (*) Actual (*) Actual Optimisation, retrofit
planning (EE
measures)
Measured Operatio
nal
Actual Actual Actual Energy Certificate,
regulations
(*) could partly be based on standard input data, depending on the purpose of
the calculation
Standard
Standard
Building geometry
Actual/standard
Climate Actual
Use Actual
Actual Tech. systems
EE Measures Investment Net savings PB
[euro] [euro/yr] [year]
1. Energy efficient showers
400 450 0,9
2. Automatic control system
20 000 12 270 1,6
3. O&M / EM 15 000 2 140 7,0
4. Heat recovery, ventilation
25 000 4 510 5,5
5. Thermostatic radiator valv
22 500 3 050 7,4
6. Insulation of pipes, valves.
9 500 1 640 5,8
7. Insulation of roof 12 500 1 970 6,4
Profitable measures 104 900 26 030 4,0
Energy Auditing of Buildings
Climate
Use
Tech. systems
Software for Auditing/Certification
Energy use
for heating & cooling
Energy need
External climate data (ISO 15927-4)
Delivered energy per energy carrier
Energy use
for hot water, ventilation, lighting, ...
Internal heat sources.
Ventilation and
transmission heat
transfer
Monthly method
Specified indoor
conditions
13790: 2008
Recoverable thermal losses
Non-recoverable
thermal losses +
auxiliary energy
Building zone
Lighting systems (EN15193-1)
Ventilation systems (EN 15241)
Room conditioning systems
(EN 15243)
Hot water systems (EN 15613-3)
Heating systems
(EN 15316-2-1, 2-3 and 3-1)
Indoor criteria, automation and
controls (EN 15251, EN 15232)
Building data (EN 15603)
Solar properties
Air flow/infiltration (EN 15242)
Transmission properties (ISO 13789)
Energy need for
heating and cooling
ENSI® EAB Software for Auditing/Certification
According ISO 13790 and other, relevant standards
Software results – existing situation
Budget item Existing
situation
Global indicator
[kWh/m² a] [kWh/m² a]
Heating 94,3 95,4
Ventilation 11,4 11,8
Domestic hot water 14,5 14,6
Fans (ventilation) 9,4 9,4
Pumps, heating 1,1 Incl. in heating
Pumps, ventilation 0,4 Incl. in ventilation
Pumps, DHW 0,1 Incl. in DHW
Pumps, cooling 0 -
Lighting 30,1 30,1
Various 8,8 -
Cooling 0 -
Total 170,1 161,3
Global indicator -
heating
Primary energy and CO2 emissions
Results – after EE measures
Budget item After
measures
Global indicator
[kWh/m² a] [kWh/m² a]
Heating 33,5 34,6
Ventilation 8,8 9,2
Domestic hot water 12,9 13,0
Fans (ventilation) 9,4 9,4
Pumps, heating 1,1 Incl. in heating
Pumps, ventilation 0,4 Incl. in
ventilation
Pumps, DHW 0,1 Incl. in DHW
Pumps, cooling 0 -
Lighting 15,0 15,0
Various 8,8 -
Cooling 0 -
Total
90,0
81,2
Global indicator -
heating
Energy efficiency of buildings in Slovakia
The energy efficiency, except of other influences, is dominantly
dependent on the physically properties of the building envelope
The assumption of their quality is given through the technical standards
Dividing the construction of buildings follows the validity of our national
standards:
Till 1950 were built buildings from brick, square roof (mostly wooden)
1951 – 1970 beginning of prefabrication, using of light beton (porous beton)
1971 – 1983 beginning of laminated constructions (sandwich construction),
light building envelopes (metal-plastic basis)
EAS v1.0
Quick and easy handling application based on European standard
The database contains:
42 apartment buildings (most built)
8 typical single family houses
Countable in two climatic zones (-12°C and -18°C)
Structure of EAS v1.0:
1. Photo documentation
2. Drawing documentation
3. Building description
4. Energy – economy calculation
5. Grafical presentation
6. What is an energy audit...
1. Photo documentation
View on the selected type of
building
Identification of the building
2. Drawing documentation
Technical recods (ground-plan,
typical floor,...)
Necessary dimensions (calculation
of heated areas,...)
Description of BE, HS, HW
EAS v1.0 - structure
3. Energy – economy calculation
Calculations of:
Energy savings
Investments
Profitability
Calculate measures individually
(depends on the customer)
Three basic domains of energy
measures:
Heating
System
Building
Envelope
EAS v1.0 - structure
Hot
Water
Prof. Application of measurement Energy saving measures
Insulation of external walls
Insulation of f loor or insulation of unheated basement
Insulation of roof
New windows
Building Env elopeBE
Table 1 Energy saving measurements of Building Envelope
Prof. Application of measurement Energy saving measures
Automatic control sy stem and temperature set back f or HS
Insulation of pipes, v alv es,... on the HS
Reconstruction of boiler room (new boiler, accessories,...)
Balancing of the HS and installation of thermostatic v alv es
Heating Sy stemHS
Table 2 Energy saving measurements of Heating System
Prof. Application of measurement Energy saving measures
Water sav ing shower heads
Thermostatic mixer, showers
New automatic control sy stem on the HW
Insulation of pipes, v alv es,... on the HW
HW Hot Water
Table 3 Energy saving measurements of Hot Water
Three basic domains of energy measures
Profession Measurements Percentage of energy saving possibilities
BE Building Env elope 20 - 30 %
HS Heating Sy stem 10 - 25 %
HW Hot Water 5 - 10 %
Table 4 Energy potential for individual energy saving measures*
Input values:
Cost of GJ heat or m3 of natural gas
Calculation of the whole building vs.
just one flat
Investments for the profitability
calculations are running behind and
they contains from costs of:
Investment
Cost of supply
Design work
Installation
Test (running, pressure,…)
Taxes (VAT)
Energy potencial
Energy – economy calculation example
Energy savings:
Building Envelope (blue)
Heating System (green)
Hot Water (red)
Energy consumption
before / after
Contribution percentage of
each profession
4. Graphical presentation
Panel buildings are dominant type of residential buildings
Energy performance of buildings - HEATING
110 ~ 140 kWh / m2 ( E –F )
40 ~ 80 kWh / m2 (B –C )
• Do not comply with current requirements on thermal protection and
energy efficiency
• High energy consumption, poor insulation, leaky constructions
(envelope, roof)
• thermal discomfort
CASE STUDY in SLOVAKIA
• To clarify the relationship between energy consumption, energy
efficiency measures and the indoor environment
• To study occupant´s behavior and habits
• To show results at three time points:
A) Before renovation
B) After renovation with no-balanced heating system
C) After complex renovation
Objective of the case study
Description- general
• Prefabricate building built in 1987
• 9.NP : 1.NP – common premises, storage space
2.-9. NP – residential
• 32 apartments
The Facade Windows, doors
Heating system and DHW
Heat sources- Heat exchange station
Distribution - Instalation space
- Instalation shafts
Description- building services
Insulation of the roof
Energy efficient measures
Insulation of the fascade
New windows, doors
Hydraulic balance of the heating system
Installation of saving shower heads
Energy audit - Energy efficient measures
Category Energy efficient measure Savings
kWh/(m2.r) %
Constructions
Insulation of the facade 13,26
15,4
Insulation of the roof 2,32 2,65
New windows 6,4 7,4
Heating system
Hydraulic balance 28,87 33,8
Temperature setback 4,21 6,5
66
Energy efficient measures
Investments
(€)
Yearly
savings
(€)
NPV
(-)
NPVQ
(-)
Insulation facade 83590 3448 8496 0,10
Insulation roof 23510 603 -8510 -0,36
New windows 22218 1664 22228 1,00
Hydraulic balance 13146 7508 95230 7,24
Temperature setback 2618 905 10452 3,99
Inflation = 4,2%
Nominal interest rate = 5%
Energy audit – Economic feasibility
Energy consumption of heating system
Year Energy consumption*
real measured values
[kWh]
Energy consumption*
values from simulation program
[kWh]
2007 248 472 239 192
2008 190 733 194 472
2009 93 095 107 344
23 %
YEAR 2009
Hydraulic balance of the
heating system
Table: Comparison of energy consumption in each year
51 %
YEAR 2008
Insulation of the facade
New window, doors
Insulation of the roof
YEAR 2007
Original conditions
After renovation with
no-balanced heating system :
After complex renovation: Before renovation :
D
106 kWh/m2 72 kWh/m2
C
35 kWh/m2
B
Energy certification
Heating system
BEFORE: 106 AFTER: 35
Domestic Hot Water system
BEFORE : 41 AFTER: 30
GLOBAL INDICATOR
BEFORE : 147 AFTER: 65
E B
D C
D B
Aim
Reducing of input values and easy handiness of our application
Accuracy from 10-20% (it can not replace computer energy evaluations)
For purposes of the First Building Society Saving Bank in Slovakia
Result for the praxis
Reduce the nowadays high energy consumption in existing buildings
Increasing of the commercial value of the building
Improvement of the living standard
Conclusion
STU, Faculty of Civil Engineering in Bratislava
