1. Carbon Reduction Strategies at the University of East Anglia
NBS-M
Carbon Reduction Strategies at the University of East Anglia
Recipient of James Watt Gold Medal
2007
N.K. Tovey (杜伟贤) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
School of Environmental Sciences / Norwich Business School

2. Original buildings Teaching wall Library Student residences
This is an ariel view of the University campus
The University was established in 1963
The original buildings are outlined in red

3. Nelson Court
Constable Terrace

4. Low Energy Educational Buildings
Thomas Paine Study Centre
Nursing and Midwifery School
ZICER
Medical School
Elizabeth Fry Building
Medical School Phase 2
You can see that the University has expanded in size
In recent years 4 educational building have been built on the campus to strenuous green design guidelines – all of which have the same construction type
EFRY – 1995
Medical School – 2001
ZICER – 2003
Nursing and Midwifery – 2005
This talk focuses on the third building – the ZICER building 4 4

5. 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. 8

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.

7. Educational Buildings at UEA in 1990s
Elizabeth Fry Building 1994
Queen’s Building 1993
Elizabeth Fry Building Employs Termodeck principle and uses ~ 25% of Queen’s Building

8. Conservation: management improvements –
User Satisfaction
thermal comfort %
air quality %
lighting %
noise %
Careful Monitoring and Analysis can reduce energy consumption.
A Low Energy Building is also a better place to work in

9. 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 50% by careful record keeping, management techniques and an adaptive approach to control. Incorporates 34 kW of Solar Panels on top floor

10. The first floor open plan office The first floor cellular offices
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
The first floor open plan office
High in thermal mass – lots and lots of concrete. The external walls are built out of dense concrete blocks with a thickness of 23cm. All the ceilings are concrete blocks.
Air tight – very little air leakage in and out of the building. So if you put heat into the building it actually stays within the building without escaping through gaps in the structure.
High insulation standards - that exceed the current UK building regulations
Triple glazing windows with low e – effectively the equivalent to quadruple glazing
The main part of the building includes
Basement ….
The first floor cellular offices

11. Regenerative heat exchanger Incoming air into the AHU
Operation of Main Building
Mechanically ventilated that utilizes hollow core ceiling slabs as supply air ducts to the space
Regenerative heat exchanger
Incoming air into the AHU 11 11

12. Air passes through hollow cores in the ceiling slabs
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 12 12

13. Recovers 87% of Ventilation Heat Requirement.
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 13 13

14. Operation of Regenerative Heat Exchangers
Stale air passes through Exchanger A and heats it up before exhausting to atmosphere
Fresh Air is heated by exchanger B before going into building B
Fresh Air
Stale Air A 14 14

15. After ~ 90 seconds the flaps switch over
Operation of Regenerative Heat Exchangers
After ~ 90 seconds the flaps switch over
Stale air passes through Exchanger B and heats it up before exhausting to atmosphere
Fresh Air is heated by exchanger A before going into building B
Fresh Air
Stale Air A 15 15

16. 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
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
Winter Day

17. 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
In late afternoon heating is turned off.
Heat is transferred to the air before entering the room
Slabs also radiate heat back into room
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
Winter Night

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
Cool air
Draws out the heat accumulated during the day
Cools the slabs to act as a cool store the following day
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
night ventilation/
free cooling
Summer night

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
Warm air
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
Summer day

20. Good Management has reduced Energy Requirements
Space Heating Consumption reduced by 57%
能源消耗（kWh/天）
800
350
原始供热方法 新供热方法 20 20

21. Life Cycle Energy Requirements of ZICER compared to other buildings
建造209441GJ
自然通风221508GJ
54%
28%
51%
34%
使用空调384967GJ
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%

22. Life Cycle Energy Requirements of ZICER compared to other buildings
Compared to the Air-conditioned office, ZICER as built recovers extra energy required in construction in under 1 year.

23. Photo shows only part of top Floor
ZICER Building
Photo shows only part of top Floor
Mono-crystalline PV on roof ~ 27 kW in 10 arrays
Poly- crystalline on façade ~ 6.7 kW in 3 arrays

24. Arrangement of Cells on Facade
Individual cells are connected horizontally
Cells active
Cells inactive even though not covered by shadow
If individual cells are connected vertically, only those cells actually in shadow are affected.
As shadow covers one column all cells are inactive 24 24 24

25. Performance of PV cells on ZICER
All arrays of cells on roof have similar performance respond to actual solar radiation
The three arrays on the façade respond differently

26.
Orientation relative to True North

28. 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

29. Original Way Heat was supplied to UEA campus
Three 8MW oil fired boilers – 85% efficient on full load, but only ~25% on low load.
Heat distributed via ~ 4 km of pipe work which was originally poorly insulated leading to losses of 500 kW or more – now ~ 200 kW.
~ 1984 small 4 MW boiler added for use at times of low demand
1987 all boilers converted to run on either gas or oil
1998 – one boiler removed and 3 CHP units installed
2004 – absorption chiller installed to provide cooling throughout campus

30. Exhaust Heat Exchanger
Conversion efficiency improvements – Building Scale CHP
3% Radiation Losses
Localised generation makes use of waste heat.
Reduces conversion losses significantly
61% Flue Losses
Exhaust Heat Exchanger
11% Flue Losses
36%
86%
Gas
50% Heat
Engine
Generator
Heat Exchanger
36% Electricity

31. UEA’s Combined Heat and Power
3 units each generating up to 1.0 MW electricity and 1.4 MW heat

32. Conversion efficiency improvements Before installation
1997/98
electricity
gas
oil
Total
MWh
19895
35148 33
Emission factor
kg/kWh
0.46
0.186
0.277
Carbon dioxide
Tonnes
9152
6538 9
15699
After installation
Electricity
Heat
1999/
2000
Total site
CHP generation
export
import
boilers
CHP
oil
total
MWh
20437
15630
977
5783
14510
28263
923
Emission factor
kg/kWh
-0.46
0.46
0.186
0.277
CO2
Tonnes
-449
2660
2699
5257
256
10422
This represents a 33% saving in carbon dioxide 32

33. Trailblazing to a Low Carbon Future
Low Energy Buildings
Photo-Voltaics
Low Energy Buildings
Absorption Chilling
Advanced CHP using Biomass Gasification
World’s First MBA in Strategic Carbon Management
Low Energy Buildings
Effective Adaptive Energy Management
Photovoltaics
Combined Heat and Power
Efficient CHP
Absorption Chilling 33 33 33

34. Load Factor of CHP Plant at UEA
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 34 34

35. Heat extracted for cooling
冷凝器 绝热
Condenser
Heat rejected
高温高压
High Temperature
High Pressure
节流阀
Throttle Valve
低温低压
Low Temperature
Low Pressure
Compressor
压缩器
蒸发器
为冷却进行热提取
Evaporator
Heat extracted for cooling
A typical Air conditioning/Refrigeration Unit

36. Heat from external source Heat extracted for cooling
Absorption Heat Pump
外部热
Heat from external source
冷凝器 绝热
Condenser
Heat rejected
高温高压
High Temperature
High Pressure
吸收器
热交换器
Absorber
Desorber
Heat Exchanger
节流阀
Throttle Valve
蒸发器
为冷却进行热提取
Evaporator
Heat extracted for cooling
低温低压
Low Temperature
Low Pressure
W ~ 0
Adsorption Heat pump reduces electricity demand and increases electricity generated

37. A 1 MW Adsorption chiller
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

38. 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%

39. Trailblazing to a Low Carbon Future
Photo-Voltaics
Efficient CHP
Absorption Chilling
Advanced Biomass CHP using Gasification 39

40. Trailblazing to a Low Carbon Future
Efficient CHP
Absorption Chilling
1990
2006
Change since 1990
2011
Students
5570
14047
+152%
16000
+187%
Floor Area (m2)
138000
207000
+50%
220000
+159%
CO2 (tonnes)
19420
21652
+11%
14000
-28%
CO2 kg/m2
140.7
104.6
-25.7%
63.6
-54.8%
CO2 kg/student
3490
1541
-55.8%
875
-74.9% 40

41. Results of the “Big Switch-Off”
Target Day
With a concerted effort savings of 25% or more are possible
How can these be translated into long term savings?

42. UEA’s Pathway to a Low Carbon Future: A summary
Good Management
Raising Awareness
Improving Conversion Efficiency
Using Renewable Energy
Don’t need the English on this slide so Chinese is fine
Offset Carbon Emissions 42 42

43. Conclusions UEA has achieved Carbon reductions by:
Constructing Low Energy Buildings
Effective adaptive energy management which has typically reduced energy requirements in a low energy building by 50% or more.
Use of Renewable Energy: Photovoltaic electric generation
but opportunities were missed which would have made more optimum use of electricity generated.
The existing CHP plant reduced carbon emissions by around 30%
Adsorption chilling has been a win-win situation reducing summertime electricity demand and increasing electricity generated locally.
Awareness raising of occupants of buildings can lead to significant savings
By the end of 2013, UEA should have reduced its carbon emissions per student by 70% compared to 1990.