Transcript Low Energy Buildings - University of East Anglia

Master Class:
25th February 2010
Presentation available at: www2.env.uea.ac.uk/gmmc/env/energy.htm
Recipient of James Watt Gold Medal
5th October 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
1
Low Carbon Strategies at the
University of East Anglia
Energy Tour
Energy and Climate Change – the
Hard Choices facing us.
2
Low Carbon Strategies at the University of
East Anglia
• Low Energy Buildings and their Management
• Low Energy Buildings and their Management
• Low Carbon Energy Provision
– Photovoltaics
– CHP
– Adsorption chilling
– Biomass Gasification
3
Original buildings
Teaching wall
Library
Student
residences
4
Nelson Court楼
Constable Terrace楼
5
Low Energy Educational Buildings
Nursing and
Midwifery Thomas Paine Study Centre
School
Medical School Phase 2
ZICER
Elizabeth Fry
Building
Medical School
6
Constable Terrace - 1993
• Four Storey Student Residence
• Divided into “houses” of 10
units each with en-suite facilities
• Heat Recovery of body and cooking
heat ~ 50%.
• Insulation standards exceed 2006
standards
• Small 250 W panel heaters in
individual rooms.
Electricity Use
Carbon Dioxide Emissions - Constable Terrace
12%
21%
140
Appliances
120
Lighting
100
MHVR Fans
MHVR Heating
18%
Panel Heaters
Hot Water
18%
Kg/m2/yr
14%
80
60
40
20
0
17%
UEA
Low
Medium
7
Educational Buildings at UEA in 1990s
Queen’s Building 1993
Elizabeth Fry Building 1994
Elizabeth Fry Building Employs Termodeck principle and uses ~
25% of Queen’s Building
8
The Elizabeth Fry Building 1994
Elizabeth Fry Binası - 1994
Cost ~6% more but has heating requirement ~20% of average
building at time.
Significantly outperforms even latest Building Regulations.
Runs on a single domestic sized central heating boiler.
Maliyeti ~%6 daha fazla olsada, ısınma
ihtiyacı zamanın ortalama binalarının ~%20’si.
En son Bina Yönetmeliklerini bile büyük
ölçüde aşmaktadır.
Tek bir ev tipi merkezi ısıtma kazanı ile
çalışmaktadır.
9
2
Toplam Enerji Tüketimi (kWh/m /yıl)
Conservation: management improvements
Koruma: yönetimde iyileştirmeler
140
120
Heating/Cooling
Hot Water
Electricity
100
80
60
40
20
0
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Careful Monitoring and Analysis can reduce energy consumption.
Dikkatli İzleme ve Analiz, enerji tüketimini azaltabilir.
10
Comparison with other buildings
Diğer Binalarla Karşılaştırma
150
2
kWh/m /yıl
200
gas
electricity
CO2/m2/yıl
250
100
50
0
Elizabeth Fry
Low Energy
Average
120
100
80
60
40
20
0
electricity
gas
Elizabeth
Fry
low energy
average
Energy Performance
Carbon Dioxide Performance
Enerji Performansı
Karbon Dioksit Performanı
11
Non Technical Evaluation of Elizabeth Fry Building Performance
Elizabeth Fry Bina Performansının Teknik Olmayan
Değerlendirmesi
User Satisfaction
Kullanıcı memnuniyeti
thermal comfort +28%
Isıl rahatlık
+%28
air quality
+36%
Hava kalitesi
+%36
lighting
+25%
aydınlatma
+%25
noise
+26%
gürültü
+%26
A Low Energy Building is also
a better place to work in.
Bir Düşük Enerji binası ayrıca
içinde çalışmak için de daha
iyi bir yerdir.
12
ZICER Building
Won the Low Energy Building of the Year Award 2005
• 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
13
The ground floor
open plan office
The first floor open
plan office
The first floor
cellular offices
14
The ZICER Building –
Main part of the building
• High in thermal mass
• Air tight
• High insulation standards
• Triple glazing with low emissivity ~
equivalent to quintuple glazing
15
Operation of Main Building
Mechanically ventilated that utilizes hollow core ceiling slabs as supply air
ducts to the space
Incoming
air into the
AHU
Regenerative heat
exchanger
16
Operation of Main Building
Filter
过滤器
Heater
加热器
Air passes through
hollow cores in the
ceiling slabs
空气通过空心的板层
Air enters the internal occupied space
空气进入内部使用空间
17
Operation of Main Building
Recovers 87% of Ventilation
Heat Requirement.
Space for future
chilling
将来制冷的空间
Out of the
building
出建筑物
The return air passes
through the heat
exchanger
空气回流进入热交换器
Return stale air is extracted from
each floor 从每层出来的回流空气
18
Fabric Cooling: Importance of Hollow Core Ceiling Slabs
Hollow core ceiling slabs store heat and cool at different times of
the year providing comfortable and stable temperatures
Warm air
Winter
Day
Warm air
Heat is transferred to the air
before entering the room
Slabs store heat from appliances
and body heat.
热量在进入房间之前被传递
到空气中
板层储存来自于电器以及人
体发出的热量
Air Temperature is
same as building fabric
leading to a more
pleasant working
environment
19
Fabric Cooling: Importance of Hollow Core Ceiling Slabs
Hollow core ceiling slabs store heat and cool at different times of
the year providing comfortable and stable temperatures
Cold air
Winter
Night
Heat is transferred to the air
before entering the room
Slabs also radiate heat back into
room
In late afternoon
heating is turned off.
热量在进入房间之前被传递到
空气中
板层也把热散发到房间内
Cold air
20
Fabric Cooling: Importance of Hollow Core Ceiling Slabs
Hollow core ceiling slabs store heat and cool at different times of
the year providing comfortable and stable temperatures
Cool air
Summer
night
Draws out the heat accumulated
during the day
Cools the slabs to act as a cool
store the following day
night ventilation/
free cooling
把白天聚积的热量带走。
冷却板层使其成为来日的冷
存储器
Cool air
21
Fabric Cooling: Importance of Hollow Core Ceiling Slabs
Hollow core ceiling slabs store heat and cool at different times of
the year providing comfortable and stable temperatures
Warm air
Summer
day
Slabs pre-cool the air before
entering the occupied space
concrete absorbs and stores heat
less/no need for air-conditioning
空气在进入建筑使用空间前被
预先冷却
混凝土结构吸收和储存了热量
以减少/停止对空调的使用
Warm air
22
Energy Consumption (kWh/day)
能源消耗（kWh/天）
Good Management has reduced Energy Requirements
Space Heating
Consumption reduced
by 57%
1000
800
800
600
400
350
200
0
-4
-2
0
2
4
6
8
10
12
14
16
18
Mean |External Temperature (oC)
Original Heating Strategy
New Heating Strategy
原始供热方法
新供热方法
23
Life Cycle Energy Requirements of ZICER compared to other buildings
与其他建筑相比ZICER楼的能量需求
自然通风
221508GJ
54%
28%
51%
使用空调
384967GJ
34%
建造
209441GJ
Materials Production 材料制造
Materials Transport 材料运输
On site construction energy 现场建造
Workforce Transport 劳动力运输
Intrinsic Heating / Cooling energy
基本功暖/供冷能耗
Functional Energy 功能能耗
Refurbishment Energy 改造能耗
Demolition Energy 拆除能耗
29%
61%
24
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
25
Low Carbon Strategies at the University of
East Anglia
• Low Energy Buildings and their Management
• Low Carbon Energy Provision
– Photovoltaics
– CHP
– Adsorption chilling
– Biomass Gasification
26
ZICER Building
Photo shows
only part of top
Floor
• Mono-crystalline PV on roof ~ 27 kW in 10 arrays
27
• Poly- crystalline on façade ~ 6.7 kW in 3 arrays
Performance of PV cells on ZICER
18
Façade
16
Roof
Output per unit area
Little difference between
orientations in winter
months
kWh / m 2
14
12
10
8
6
4
2
0
Jan Mar May Jul Sep Nov Jan Mar May Jul Sep Nov
Load factors
Façade:
2% in winter
~8% in summer
Roof
2% in winter
15% in summer
2005
16%
façade
roof
average
14%
12%
Load Factor
2004
10%
8%
6%
4%
2%
0%
Jan Mar May Jul Sep Nov Jan Mar May Jul Sep Nov
2004
2005
28
Performance of PV cells on ZICER
Wh
%
100
100
Block1
90
90
Block 2
80
80
Block 3
70
70
Block 4
60
60
Block 5
50
50
Block 6
40
40
Block 7
30
30
Block 8
20
20
Block 9
10
10
Block 10
0
0
radiation
9
10
11
12
13
14
All arrays of cells on roof
have similar performance
respond to actual solar
radiation
15
Time of day
%
Wh
The three arrays on the
façade respond differently
200
180
160
140
120
100
80
60
40
20
0
100
90
80
70
60
50
40
30
20
10
0
9
10
11
12
13
Time of Day
14
15
Top Row
Middle Row
Bottom Row
radiation
29
Elevation in the sky (degrees)
20
18
16
14
12
10
8
6
4
2
0
120
8.00
9.00
150
10.00
180
210
12.00
13.00
14.00
Orientation relative to True North
11.00
15.00
240
16.00
30
Elevation in the sky (degrees)
25
January
May
September
P1 - bottom PV row
February
June
October
P2 - middle PV row
March
July
November
P3 - top PV row
April
August
December
20
15
10
5
0
6.00
7.00
8.00
9.00
10.00
11.00
12.00
Time (hours)
13.00
14.00
15.00
16.00
31
Arrangement of Cells on Facade
Individual cells are connected
horizontally
Cells active
Cells inactive even though
not covered by shadow
As shadow covers one column
all cells are inactive
If individual cells are connected
vertically, only those cells actually in
shadow are affected.
32
32
Use of PV generated energy
Peak output is 34 kW 峰值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
33
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
34
Efficiency of PV Cells
Mono-crystalline Cell Efficiency
• Peak Cell efficiency is ~ 14% and
close to standard test bed efficiency.
• Most projections of performance use
this efficiency
• Average efficiency over year is 11.1%
Poly-crystalline Cell Efficiency
• Peak Cell efficiency is ~ 9.5%.
• Average efficiency over year is
7.5%
Inverter Efficiencies reduce overall system efficiencies to
10.1% and 6.73% respectively
35
Life Cycle Issues
Monocrystalline
(kWh/kWp)
Polycrystalline
(kWh/kWp)
arising from Electricity use in manufacture)
3230
2750
Array supports and system connections
285
285
On site Installation energy
131.4
131.4
Transportation Spain > Germany > UK
11250 vehicle-kilometres
453.2
453.2
4.1
3.4
Embodied Energy in PV Cells (most
Total
Energy Yield Ratios
Mono-crystalline Cells
As add on features
Integrated into design
MWh/kWp
Life Time of cells (years)
20
3.2
3.5
25
3.8
4.2
30
4.6
5.4
36
Conversion efficiency improvements – Building Scale CHP
3% Radiation Losses
11%
61% Flue
Flue Losses
Losses
36%
86%
Gas
Localised generation makes use of
waste heat.
Reduces conversion losses
significantly
Exhaust
Heat
Exchanger
Engine
Heat Exchanger
Generator
36% Electricity
50% Heat
37
UEA’s Combined Heat and Power
3 units each generating up to 1.0 MW electricity and 1.4 MW
heat
38
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
9
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
39
Conversion efficiency improvements
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
40
绝热
Heat rejected
高温高压
High Temperature
High Pressure
节流阀
Throttle
Valve
Compressor
冷凝器
Condenser
蒸发器
Evaporator
低温低压
Low Temperature
Low Pressure
压缩器
为冷却进行热提
取
Heat extracted
for cooling
A typical Air conditioning/Refrigeration Unit
41
Absorption Heat Pump
外部热
Heat from
external source
绝热
Heat rejected
高温高压
High Temperature
High Pressure
吸收器
Desorber
节流阀
Throttle
Valve
冷凝器
Condenser
蒸发器
Evaporator
为冷却进行热提
取
Heat extracted
for cooling
低温低压
Low Temperature
Low Pressure
热交换器
Heat
Exchanger
W~0
吸收器
Absorber
Adsorption Heat pump reduces electricity demand
and increases electricity generated
42
A 1 MW Adsorption chiller
1 MW 吸附冷却器
• Uses Waste Heat from CHP
• provides most of chilling requirements
in summer
• Reduces electricity demand in summer
• Increases electricity generated locally
• Saves ~500 tonnes Carbon Dioxide annually
43
The Future: Biomass Advanced Gasifier/ Combined Heat and Power
•
•
•
•
•
Addresses increasing demand for energy as University expands
Will provide an extra 1.4MW of electrical energy and 2MWth heat
Will have under 7 year payback
Will use sustainable local wood fuel mostly from waste from saw
mills
Will reduce Carbon Emissions of UEA by ~ 25% despite increasing
student numbers by 250%
44
Trailblazing to a Low Carbon Future
Low Energy Buildings
Low Energy Buildings
Photo-Voltaics
• Low Energy Buildings
• Absorption Chilling
• Effective Adaptive Energy
Management
• Advanced CHP using
Biomass Gasification
• Photovoltaics
Efficient CHP
• Combined Heat and Power
Absorption Chilling
• World’s First MBA in
Strategic Carbon
Management
45
45
45
Trailblazing to a Low Carbon Future
Photo-Voltaics
Efficient CHP
Advanced Biomass CHP using Gasification
Absorption Chilling
46
46
46
Trailblazing to a Low Carbon Future
Efficient CHP
1990
2006
Students
Floor Area (m2)
5570
138000
CO2 (tonnes)
CO2 kg/m2
CO2 kg/student
Absorption Chilling
14047
207000
Change since
1990
+152%
+50%
2010
16000
220000
Change since
1990
+187%
+159%
19420
140.7
21652
104.6
+11%
-25.7%
14000
63.6
-28%
-54.8%
3490
1541
-55.8%
875
-74.9%
47
47
47
Now the Energy Tour
• Elizabeth Fry Building
• ZICER Building
• Boiler House
48
Conclusions
• Hard Choices face us in the next 20 years
• Effective adaptive energy management can reduce heating
energy requirements in a low energy building by 50% or more.
• Heavy weight buildings can be used to effectively control energy
consumption
• 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
49