Transcript The Zicer building, its construction and

A Stern Warning
The Zicer building, its construction and
performance and other Low Carbon Strategies
at UEA.
24th May 2007
CRed
Carbon Reduction
Keith Tovey (杜伟贤) M.A., PhD, CEng, MICE, CEnv
Energy Science Director: CRed HSBC Director of Low Carbon Innovation
School of Environmental Sciences, University of East Anglia
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Original buildings
Teaching wall
Library
Student
residences
2
Nelson Court
Constable Terrace
3
Low Energy Educational Buildings
Nursing and
Midwifery
School
Medical School Phase 2
ZICER
Elizabeth Fry
Building
Medical School
4
The Elizabeth Fry Building 1994
Cost ~6% more but has heating requirement ~25% of average building at time.
Building Regulations have been updated: 1994, 2002, 2006, but building
outperforms all of these.
Runs on a single domestic sized central heating boiler.
Would have scored 13 out of 10 on the Carbon Index Scale.
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8
Conservation: management improvements –
250
gas
200
kWh/m2/yr
electricity
150
100
50
0
Elizabeth Fry
Low
Average
User Satisfaction
thermal comfort +28%
air quality
+36%
lighting
+25%
noise
+26%
A Low Energy Building is
also a better place to work in
Careful Monitoring and Analysis can reduce energy
consumption.
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ZICER Building
Low Energy Building of the Year Award 2005 awarded
by the Carbon Trust.
Heating Energy consumption as new in 2003 was reduced by further 57%
by careful record keeping, management techniques and an adaptive
approach to control.
Incorporates 34 kW of Solar Panels on top floor
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The ZICER Building Description
• Four storeys high and a basement
• Total floor area of 2860 sq.m
• Two construction types
Main part of the building
• High in thermal mass
• Air tight
• High insulation standards
• Triple glazing with low emissivity
~ U – value ~ 1.0 W m2 K-1
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The ground floor
open plan office
The first floor
open plan office
The first floor
cellular offices
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ZICER Building
Photo shows
only part of top
Floor
•
•
•
•
Top floor is an exhibition area – also to promote PV
Windows are semi transparent
Mono-crystalline PV on roof ~ 27 kW in 10 arrays
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Poly- crystalline on façade ~ 6/7 kW in 3 arrays
Operation of the Main Building
• Mechanically ventilated that utilizes hollow core ceiling
slabs as supply
air ducts to the space
Regenerative
heat
Space for future
exchanger
chilling
Incoming
Filter Heater
air into
the AHU
The air passes
through hollow
cores in the
ceiling slabs
Recovers 87% of
Ventilation Heat
Requirement.
The
Out
of return
the air passes
through the heat
building
Return stale air is
Air enters the internal
exchanger
extracted from each floor occupied space
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used to store heat
and coolness at different times of the year to provide
comfortable and stable temperatures
Cold air
night ventilation/
free cooling
Draws out the heat
accumulated during
Cools the slabs to
the day
act as a cool store
the following day
Summer
night
Cold air
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used to store heat
and coolness at different times of the year to provide
comfortable and stable temperatures
Warm
air
The concrete
Pre-cools
thestores
air
absorbs and
before
entering
thea
the heat
– like
occupiedinspace
radiator
reverse
Warm
air
Summer
day
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used to store heat
and coolness at different times of the year to provide
comfortable and stable temperatures
Winter Day
TheHeat
concrete
is
slabs
transferred
absorbs
to the
and
air before
store heat
entering
the room
Winter
day
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used to store heat
and coolness at different times of the year to provide
comfortable and stable temperatures
Winter
Night air
When
the internal
temperature drops,
heat stored in the
concrete is emitted
back into the room
Winter
night
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Performance of ZICER Building
2004
2005
EFry
ZICER
New Management
• Initially performance was poor
• Performance improved with new Management Strategy
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Good Management has reduced Energy Requirements
The Energy Signature from the Old and the New Heating
Strategies
Heating and hot-water
consumption (kWh/day)
1000
The space heating
consumption has
reduced by 57%
800
800
600
400
350
200
0
-4
-2
0
2
4
6
8
10
12
14
16
18
Mean external temperature over a 24 hour period (degrees C)
New Heating Strategy
Acknowledgement: Charlotte Turner
Original Heating Strategy
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Effect of New Control Strategies on Thermal Comfort
Winter
Summer
50
50
Year 2
Year 1
30
20
Year 2
30
20
10
10
0
0
-3
-2
-1
Year 1
40
Percentage
Percentage
40
0
1
2
3
-3
-2
-1
Actual Vote
Winter
0
Actual Vote
1
2
3
Summer
Number
Mean Vote
Number
Mean Vote
2004
224
0.10
352
0.12
2005
256
0.12
273
0.44
Only data for relevant Metabolic Rates included in above table
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Performance of PV cells on ZICER
70
7000
PV electricity
PV % of total
6000
60
5000
50
4000
40
3000
30
2000
20
1000
10
0
(Jan ) 1
PV percentage of the total electricity usage
Electricity used/generated (kWh)
Electricity from conventional sources
0
(Mar) 11
(May) 21
(Aug) 31
Time (week number)
(Oct) 41
(Dec) 51
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Arrangement of Cells
on Facade
Individual cells are
connected horizontally
As shadow covers one column
all cells are inactive
If individual cells are connected
vertically, only those cells actually in
shadow are affected.
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Use of PV generated energy
Peak output is 34 kW
Sometimes electricity is exported
Inverters are only 91% efficient
Most use is for computers
DC power packs are inefficient
typically less than 60% efficient
Need an integrated approach
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Performance of PV cells on ZICER
Cost of Generated Electricity
Actual Situation excluding
Grant
Actual Situation with
Grant
Discount rate
3%
5%
7%
3%
5%
7%
Unit energy cost per
kWh (£)
1.29
1.58
1.88
0.84
1.02
1.22
Avoided cost exc. the
Grant
Avoided Costs with Grant
Discount rate
3%
5%
7%
3%
5%
7%
Unit energy cost per
kWh (£)
0.57
0.70
0.83
0.12
0.14
0.16
Grant was ~ £172 000 out of a total of ~ £480 000
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Conversion efficiency improvements – Building Scale CHP
3% Radiation Losses
11%
61% Flue
Flue Losses
Losses
Exhaust
Heat
Exchanger
36%
86%
GAS
efficient
Localised generation
makes use of waste heat.
Reduces conversion
losses significantly
Engine
Engine heat Exchanger
Generator
36%
Electricity
50% Heat
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Conversion efficiency improvements
Before installation
1997/98
MWh
electricity
gas
oil
19895
35148
33
Total
Emission factor
kg/kWh
0.46
0.186
0.277
Carbon dioxide
Tonnes
9152
6538
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Electricity
After installation
1999/
Total
CHP export
2000
site generation
MWh 20437 15630
977
Emission kg/kWh
-0.46
factor
CO2
Tonnes
-449
15699
Heat
import boilers CHP
oil
total
5783
14510 28263 923
0.46
0.186
0.186 0.277
2660
2699
5257 256 10422
This represents a 33% saving in carbon dioxide
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Energy Conversion
efficiency improvements
3000
2500
CHP
Import
Export
2000
Performance of
UEA CHP plant
1500
1000
500
0
-500
1999 - 00
2000 - 01
2001 - 02
2002 - 03
2003 - 04 2004 - 05
Load Factor of
CHP Plant at UEA
Demand for Heat is low in
summer: plant cannot be
used effectively
More electricity could be
generated in summer
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Conversion efficiency improvements
Normal Chilling
Adsorption
Chilling
Heat from external
source
Heat rejected
High Temperature
High Pressure
Desorber
Heat
Compressor
Exchanger
Condenser
Throttle
Valve
W~0
Evaporator
Absorber
Heat extracted
for cooling
Low Temperature
Low Pressure
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A 1 MW Adsorption
chiller
1 MW 吸附冷却器
• Adsorption Heat pump uses Waste Heat from CHP
•
•
•
•
Will provide most of chilling requirements in summer
Will reduce electricity demand in summer
Will increase electricity generated locally
Save 500 – 700 tonnes Carbon Dioxide annually
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Life Cycle Energy Requirements of ZICER as built compared to
other buildings of same size and design
Main TermoDeck Building only
54%
Naturally
Ventilated
221508GJ
28%
As Built
209441GJ
51%
Materials Production
Materials Transport
On site construction energy
Workforce Transport
Intrinsic Heating / Cooling energy
Functional Energy
Refurbishment Energy
Demolition Energy
Air Conditioned
384967GJ
34%
29%
61%
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Life Cycle Energy Requirements of ZICER compared to other buildings
300000
ZICER
250000
Naturally Ventilated
GJ
200000
Air Conditrioned
150000
100000
50000
0
0
5
10 15 20 25 30 35 40 45 50 55 60
80000
Years
GJ
60000
Compared to the Air-conditioned
office, ZICER as built recovers
extra energy required in
construction in under 1 year.
40000
20000
ZICER
Naturally Ventilated
Air Conditrioned
0
0
1
2
3
4
5
6
7
8
9
10
Years
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Conclusions
• Buildings built to low energy standards have cost ~ 5% more,
but savings have recouped extra costs in around 5 years.
• Ventilation heat requirements can be large and efficient heat
recovery is important.
• Effective adaptive energy management can reduce heating
energy requirements in a low energy building by 50% or more.
• Photovoltaic cells need to take account of intended use of
electricity use in building to get the optimum value.
• Building scale CHP can reduce carbon emissions significantly
• Adsorption chilling should be included to ensure optimum
utilisation of CHP plant, to reduce electricity demand, and allow
increased generation of electricity locally.
• Promoting Awareness can result in up to 25% savings
• The Future for UEA: Biomass CHP? Wind Turbines?
"If you do not change direction, you may end up where
you are heading."
Lao Tzu (604-531 BC) Chinese Artist and Taoist philosopher
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A Stern Warning
24th May 2007
The Zicer building, its construction and performance
and other Low Carbon Strategies at UEA.
This presentation is now accessible on the WEB at:
www2.env.uea.ac.uk/cred/creduea.htm
see also www.cred-uk.org
Keith Tovey (杜伟贤)
CRed
Carbon Reduction
Energy Science Director CRed
HSBC Director of Low Carbon Innovation
Acknowledgement: Charlotte Turner
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