CRed Carbon Reduction 1 Environmental Challenges: Low Carbon Strategies at the University of East...

CRedCarbon Reduction

1

Environmental Challenges: Low Carbon Strategies at the University of East Anglia

Rotary Friendship Exchange Visit - 19th September 2008

Recipient of James Watt Gold Medal5th October 2007

Keith Tovey ( 杜伟贤 ) Н.К.Тови M.A., PhD, CEng, MICE, CEnv Energy Science Director: Low Carbon Innovation Centre

School of Environmental Sciences, UEA

Keith Tovey: Junior Vice-President Rotary Club of Norwich


University of East Anglia

Founded in 1963 with 87 students

• 45 years old next month

• Currently over 12000 students

• 2000+ staff

University Sites

• The Plain

• Earlham Hall (School of Law)

• The Village (Student Accommodation)

• School of Nursing


School of Environmental Sciences

A World Renowned 5** Research Department• Excellent Teaching Rating• Several Important Research Units with School

Centre for Ecology, Evolution and Conservation (CEEC)

Centre for Economic and Behavioural Analysis of Risk & Decision (CEBARD)

Centre for Environmental Risk (CER)

Centre for Social and Economic Research on the Global Environment (CSERGE)

Climatic Research Unit (CRU)

Community Carbon Reduction Project (CRed)

East Anglian Business Environment Club (EABEC)

Zuckerman Institute for Connective Environmental Research (ZICER)

Laboratory for Global Marine & Atmospheric Chemistry (LGMAC)

Tyndall Centre for Climate Change Research (TYN)

WeatherQuest Ltd

Original buildings

Library

Student residences

Teaching wall

Nelson Court

Constable Terrace

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

21%

18%

17%

18%

14%

12%

Appliances

Lighting

MHVR Fans

MHVR Heating

Panel Heaters

Hot Water

Carbon Dioxide Emissions - Constable Terrace

0

20

40

60

80

100

120

140

UEA Low Medium

Kg

/m2 /y

r

Low Energy Educational Buildings

Nursing and Midwifery School

Elizabeth Fry Building

ZICER

Medical School

Medical School Phase 2

88

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.

Quadruple Glazing

Thick Insulation

Air circulates through whole fabric of building

Principle of Operation of TermoDeck Construction

Exhaust air passes through a two channel regenerative heat exchanger which recovers 85+% of ventilation heat requirements.

Mean Surface Temperature close to Air Temperature

1010

Conservation: management improvements –

Careful Monitoring and Analysis can reduce energy consumption.

0

50

100

150

200

250

Elizabeth Fry Low Average

kWh/

m2/

yr

gas

electricity

thermal comfort +28%User Satisfaction

noise +26%

lighting +25%

air quality +36%

A Low Energy Building is also a better place to work in

0

20

40

60

80

100

120

140

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004

Ene

rgy

Con

sum

ptio

n kW

h/m

2 /ann

um Heating/Cooling Hot Water Electricity

1111

ZICER Building

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

Low Energy Building of the Year Award 2005 awarded by the Carbon Trust.

1212

The ground floor open plan office

The first floor open plan office

The first floor cellular offices

Incoming air into

the AHU

Regenerative heat exchanger

Operation of Main BuildingMechanically ventilated using hollow core slabs as air supply ducts.

Air enters the internal occupied space

Filter Heater

Air passes through hollow

cores in the ceiling slabs

Operation of Main Building

Return stale air is extracted

Return air passes through the heat exchanger

Out of the building

Operation of Main Building

Recovers 87% of Ventilation Heat Requirement.

Space for future chilling

Operation of Regenerative Heat Exchangers

Fresh Air

Stale Air

Fresh Air

Stale Air

A

B

B

A

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

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

After ~ 90 seconds the flaps switch over

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.

Heat is transferred to the air before entering

the room

Slabs store heat from appliances and body

heat

Winter Day

Air Temperature is same as building fabric leading to a more pleasant working environment

Warm air

Warm air



Heat is transferred to the air before entering

the room

Slabs also radiate heat back into room

Winter Night

In late afternoon heating is turned off.

Cool air

Cool air



Draws out the heat accumulated during the

day

Cools the slabs to act as a cool store the following day

Summer night

night ventilation/ free cooling

Cold air

Cold air



Slabs pre-cool the air before entering the

occupied spaceconcrete absorbs and stores heat less/no need for air-

conditioning

Summer day

Warm air

Warm air

0

200

400

600

800

1000

-4 -2 0 2 4 6 8 10 12 14 16 18

Mean |External Temperature (oC)

En

ergy

Con

sum

pti

on (

kW

h/d

ay)

Original Heating Strategy New Heating Strategy

O

Good Management has reduced Energy Requirements

800

350

Space Heating Consumption reduced by 57%

22

As Built 209441GJ

Air Conditioned 384967GJ

Naturally Ventilated 221508GJ

Life Cycle Energy Requirements of ZICER as built compared to other heating/cooling strategies

Materials Production

Materials Transport

On site construction energy

Workforce Transport

Intrinsic Heating / Cooling energy

Functional Energy

Refurbishment Energy

Demolition Energy

28%54%

34%51%

61%

29%

23

0

50000

100000

150000

200000

250000

300000

0 5 10 15 20 25 30 35 40 45 50 55 60

Years

GJ

ZICER

Naturally Ventilated

Air Conditrioned

Comparison of Life Cycle Energy Requirements of ZICER

Compared to the Air-conditioned office, ZICER recovers extra energy required in construction in under 1 year. 0

20000

40000

60000

80000

0 1 2 3 4 5 6 7 8 9 10

Years

GJ

ZICER

Naturally Ventilated

Air Conditrioned

Comparisons assume identical size, shape and orientation

2424

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

• Poly- crystalline on façade ~ 6/7 kW in 3 arrays

2525

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.

2626

Use of PV generated energy

Sometimes electricity is exportedInverters are only 91% efficient

Most use is for computers

DC power packs are inefficient typically less than 60% efficientNeed an integrated approach

Peak output is 34 kW

2727

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

Performance of PV cells on ZICER

Cost of Generated Electricity

28

EngineGenerator

36% Electricity

GAS

11% Flue Losses3% Radiation Losses

Conversion efficiency improvements – Building Scale CHP

61% Flue Losses

36%

efficient

29

EngineGenerator

36% Electricity

50% Heat

GAS

Engine heat Exchanger

Exhaust Heat

Exchanger

11% Flue Losses3% Radiation Losses

86%

efficient

Localised generation makes use of waste heat.

Reduces conversion losses significantly

Conversion efficiency improvements – Building Scale CHP

UEA’s Combined Heat and Power

3 units each generating up to 1.0 MW electricity and 1.4 MW heat

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Conversion efficiency improvements

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

Electricity Heat

1999/2000

Total site

CHP generation

export import boilers CHP oil total

MWh 20437 15630 977 5783 14510 28263 923Emission

factorkg/kWh -0.46 0.46 0.186 0.186 0.277

CO2 Tonnes -449 2660 2699 5257 256 10422

Before installation

After installation

This represents a 33% saving in carbon dioxide

3232

Conversion efficiency improvements

Load Factor of CHP Plant at UEA

Demand for Heat is low in summer: plant cannot be used effectivelyMore electricity could be generated in summer

3333

Conversion Efficiency Improvements

Condenser

Evaporator

Throttle Valve

Heat rejected

Heat extracted for cooling

Normal Chilling

Compressor

High

TemperatureHigh

Pressure

Low TemperatureLow Pressure

3434

Condenser

Evaporator

Throttle Valve

Heat rejected

Heat extracted for cooling

High TemperatureHigh Pressure


Heat from external source

Absorber

Desorber

Heat Exchanger

W ~ 0

Adsorption Chilling

Conversion Efficiency Improvements

High Temperature

High Pressure


3535

A 1 MW Adsorption chiller

• 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

The Future: Advanced Gasifier Biomass CHP Plant

UEA has grown by over 40% since 2000 and energy demand is increasing.

• New Biomass Plant will provide an extra 1.4MWe , and 2MWth

• Will produce gas from waste wood which is then used as fuel for CHP plant

• Under 7 year payback

• Local wood fuel from waste rom waste wood and local sustainable wood and local sustainable sourcessources

• Will reduce Carbon Emissions of UEA by a further 35%

38

Reduction with biomass

Reducing Carbon Emissions at the University of East Anglia

Reduction with biomass

When completed the biomass station will reduce total emissions by 32% compared to 2006 and 24.5% compared to 1990

39

Target Day

Results of the “Big Switch-Off”

With a concerted effort savings of 25% or more are possibleHow can these be translated into long term savings?

UK Geographical Spread of CRed

Community focused148,000 pledges45,000 peopleGrowing at 1-2% per month

41

How many people know what 9 tonnes of CO2 looks like?

UK emissions is equivalent to 5 hot air balloons per person per year.

In the developing world, the average is under 1 balloon per person

On average each person causes emission of CO2 from energy used.

UK ~9 tonnes of CO2 each year.

France ~6.5 tonnes

Germany ~ 10 tonnes

USA ~ 20 tonnes

"Nobody made a greater mistake than he who did nothing because he thought he could do only a little."

Edmund Burke (1727 – 1797)

• Filling up with petrol (~£45 for a full tank – 40 litres) --------- 90 kg of CO2 (5% of one hot air balloon)

42

Raising Awareness• A tumble dryer uses 4 times as much energy as a washing

machine. Using it 5 times a week will cost over £100 a year just for this appliance alone and emit over half a tonne of CO2.

• 10 gms of carbon dioxide has an equivalent volume of 1 party balloon.

• Standby on electrical appliances 60+ kWh a year - 3000 balloons at a cost of over £6 per year

How far does one have to drive in a small family car (e.g. 1400 cc Toyota Corolla) to emit as much carbon dioxide as heating an old persons room for 1 hour?

1.6 miles

At Gao’an No 1 Primary School in Xuhui District, Shanghai

School children at the Al Fatah University, Tripoli, Libya

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A Pathway to a Low Carbon Future for business

4. Renewable Energy

5. Offsetting

Green Tariffs

3. Technical Measures

1. Awareness

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800

1000

-4 -2 0 2 4 6 8 10 12 14 16 18

Mean |External Temperature (oC)

En

ergy

Con

sum

pti

on (

kW

h/d

ay)

Original Heating Strategy New Heating Strategy

O

2. Management

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World’s First MBA in Strategic Carbon Management

First cohort January 2008

A partnership between

The Norwich Business School and the 5** School of Environmental Sciences

Sharing the Expertise of the University

45

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.

• Promoting Awareness can result in up to 25% savings

• The Future for UEA: Biomass CHP Wind Turbines?


Lao Tzu (604-531 BC) Chinese Artist and Taoist philosopher

"If you do not change direction, you may end up where you are heading."

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