Even Better than the Best Building Ever?The ZICER and Elizabeth Fry Low Energy Buildings

Keith Tovey M.A., PhD, CEng, MICEEnergy Science Director: Low Carbon Innovation Centre

School of Environmental Sciences

Main Energy Conservation Projects at UEA

• Constable Terrace/ Nelson Court Student Residences

• Elizabeth Fry Building

• Combined Heat and Power

• School of Medicine

• ZICER Building

The Future

• Absorption Chilling

Constable Terrace - 1993

Constable Terrace – Key Points

• Four Storey Student Residence

• Divided into “houses” of 10 units each with en-suite facilities

• Common Room/ Kitchen for each house

• Each house has a mechanical heat recovering Air Handling Unit which recovers much of the heat from cooking, appliance use, body heat etc.

• Fresh Air is fed via the AHUs for heating, and additional heat is provided electrically

• Individual rooms are provided with small 250W panel supplementary heaters

Constable Terrace – Key Points

• Constructed in 1992/1993

• 100mm insulation on floor – U value 0.18 W m-2 K [ Standard U – Value at time 0.45 W m-2 K (0.25 W m-2 K in 2002)]

• Walls: 2 leaves of lightweight concrete blocks with 100 mineral fibre cavity insulation – U value (0.22 W m-2 K) [ Standard U – Value at time 0.45 W m-2 K (0.35 W m-2 K in 2002)]

• Roof: 200 mm insulation – U value (0.15 W m-2 K) [ Standard U – Value at time 0.25 W m-2 K (0.16 W m-2 K in 2002)]

• Specified pressure test at 50 Pa – 1 ach ~ 0.05 ach @ normal pressure[ actual performance – 2 ach – but much better than conventional buildings]

Energy Use - Constable Terrace

0

50

100

150

200

250

300

350

UEA Low Medium

Kw

h/m

2 /yr

Fossil Fuel

Electricity

Carbon Dioxide Emissions - Constable Terrace

0

20

40

60

80

100

120

140

UEA Low Medium

Kg

/m2 /y

r

Constable Terrace

Comparison of Constable Terrace with DOE standards

Electricity Use

21%

18%

17%

18%

14%

12%

Appliances

Lighting

MHVR Fans

MHVR Heating

Panel Heaters

Hot Water

The Elizabeth Fry Building

The Elizabeth Fry Building

•Termodeck Construction

•Air is circulated through whole fabric of building

•Heated using a normal domestic heating boiler (24 kW)

•No heat supply needed at temperatures as cool as 9oC

•Triple glazing with Low Emissivity Glass ~ quadruple glazing

•180 mm insulated cavity

•300 mm roof insulation

•100 mm floor insulation

•Air – Pressure Test at 50 Pa – not to exceed 1.0 ach

• Actual performance 0.97 ach

• Has deteriorated slightly since 1996

• Uses regenerative Heat Exchangers 85% with heat recovery

Fresh Air

Stale Air

Stale Air

Fresh Air

Operation of Regenerative Heat Exchangers

Winter heating

Experience shows that slab pre-heating is usually unnecessary – when used – often results in excess heat expelled later in day by AHUs

Summer Cooling

Slab temperature > 2oC above ambient

Cool air at night is circulated around slab to cool building

No air-conditioning required

In early years performance was not optimised

In later years energy efficiency has improve

even though air-tightness has deteriorated

Electricity Comsumption - Elzabeth Fry

0

20

40

60

80

100

120

140

Elizabeth Fry low average

kWh

/m2/y

rGas Consumption - Elizabeth Fry

0

50

100

150

200

250

Elizabeth Fry Low Average

kWh

/m2/y

r

Heating/Hot Water

0102030405060708090

1995 1996 1997

kW

h/m

2/yr

Hot Water

Space Heating

The performance of the building has improved with

time

Energy Consumption in Elizabeth Fry

Heating provided by domestic sized boilers.

Energy requirement 20% of good practice for Academic Buildings.

44

96

ECON 19 Good PracticeType 3 Office

Elizabeth Fry

100

90

80

70

60

50

40

30

20

10

0

kg/m2/an

num

gas electricity

carbon dioxide emissions

thermal comfort +28%

air quality +36%

lighting +25%

noise +26%

Elizabeth Fry

User Satisfaction

An energy efficient building reduces carbon dioxide

AND

is a better building to work in.

Elizabeth Fry: Carbon Dioxide Emissions and User Satisfaction

EFRY average yearly energy consumption for heating and hot-water

0

10

20

30

40

50

60

70

1995 1996 1997 1998 1999 2000 2001 2002 2003

year

ener

gy c

onsu

mpt

ion

(kW

h/m

2/ye

ar)

energy consumption

Normalised energy consumption to the year 2000'sdegree daysA new heating strategy was

introduced in March 1996

The ZICER Building

• Follows the tradition of the Elizabeth Fry Building

• Uses Termodeck construction

• Draws heat from University Heating Main

• Has a 34 kW array of Photo Voltaic cells on top floor and roof

Zuckerman Institute for Connective Environmental

Research

ZICER Construction

ZICER Construction

ZICER Construction

Ducts in floor slab

Installation of Solar Panels

0

10

20

30

40

50

Eli

za

be

thF

ry (

Ne

w)

Eli

za

be

thF

ry (

20

02

)

ZIC

ER

kg

CO

2/m

2/y

r

gas

electricity

Elizabeth Fry performance has improved over years. ZICER will be better and less than 70% of emissions of mid 90’s best practice building

Photovoltaic cells will generate ~ 30 kW and save 20 tonnes CO2 per annum.

Projected Performance of ZICER

Variation of Carbon Emission and Carbon Index with Building Regulations

0

10

20

30

40

50

60

70

0 1 2 3 4 5 6 7 8 9 10

Carbon Index

kg

CO

2/m

2 /yr

1976

19901985

2002

1994

Elizabeth FryZICER

Theorectical Perfection in 2002 Regulations

pre-war

1955

1965

Variation of Carbon Emission and Carbon Index problems with current Building Regulations

0

2

4

6

8

10

12

14

16

18

20

7 8 9 10

Carbon Indexk

g C

O2/

m2 /y

r 2002

Elizabeth FryZICER

Theorectical Perfection in 2002 Regulations

Performance of Elizabeth Fry and ZICER

UEA Combined Heat and Power Scheme

UEA CHP Scheme

• Until 1999 most heat for space heating was supplied by large boilers

• Primary main temperature ~ 110 – 120oC

• All electricity imported

• Energy bill was in excess of £1 million per year

• Three 1 MWe generators are now installed

• Provide the majority of the electricity for the campus

• Export electricity at periods of low demand

• Waste heat is used a primary heat source

• Supplemented by existing boilers

• CHP has reduced that figure by £400 000 per year

CHP Review

839015101.79.26537.68555.0tonnes   0.2770.1860.43kg/kWh   331503514815819895328kWh1997/98balloons  totaloilgaselectricity  

571010278.0255.55256.92698.90.02486.7-420.1 tonnes 

  0.2770.1860.186 0.43-0.43 kg/ kWh 

  922563282630771451007815630431578310097700020436531kWh1999/00

balloonstotaloilCHPboilersGener-ationimportexportelectricity  

Saving in CO2 emissions as a result of CHP - 4824 tonnes CO2 or 31.9%

Equivalent to 2680 hot air balloons.

[Note: UEA expanded during time and consumption increased so CO2 savings are really higher than this].

CHP Review

• Installation of CHP units reduced carbon dioxide emissions by around 8000 tonnes or 35%.

• Reduced primary heating main temperature > lower distribution losses

• Extends the life of the boiler house plant,

In summer

• Heat Dump fans must be used to remove excess heat

• The heat demand in summer dictates how much electricity can be generated

In summer

• Increased demand for cooling of scientific equipment

• A 1MW absorption chiller is currently under installation

Condenser

Evaporator

Throttle Valve

Heat rejected

Heat extracted for cooling

High TemperatureHigh Pressure

Low TemperatureLow Pressure

Absorber

Desorber

Heat Exchanger

Heat from external source

W ~ 0

Absorption Heat Pump

UEA has been leading the way with energy conservation.

Technically

• Constable Terrace

• Elizabeth Fry

• ZICER

• CHP

• Absorption Chilling

CRed is pioneering ways in which to reduced carbon dioxide emissions

• Building partnerships

• Education

• Working in an integrated way

Concluding Remarks

N. Keith Tovey, MA, PhD, C.Eng, MICELow Carbon Innovation Centre

University of East AngliaNorwich

Н.К.Тови М.А., д-р технических наукФакультет экологических исследований

Университета Восточной Англии