Experience at the University of East Anglia Chongqing - 23rd September Low Energy Buildings and Low Carbon Strategies Keith Tovey ( ) M.A., PhD, CEng, MICE HSBC Director of Low Carbon Innovation: and Charlotte Turner: School of Environmental Sciences CRed

Construction of Low Energy Buildings Careful Monitoring of performance and adaptation where relevant Fuel efficient and alternative methods to provide energy Promoting awareness among occupants Tackling issues for reducing energy in existing buildings which are Grade 2 listed and of historic interest. Low Energy and Low Carbon Strategies at UEA

Low Energy Student Residences e.g. Constable Terrace Low Energy Educational Buildings using TermoDeck construction Elizabeth Fry Building ZICER Building Low Energy Building Projects at UEA In all cases Capital Cost was an issue The Termodeck buildings cost just 5% more yet consume only one quarter of energy

Constable Terrace

Low Energy Building Projects at UEA Student Residence: Constable Terrace – 1993 Over 50% of ventilation heat is recovered U-Values (Wm -2 K -1 ) WallsWindowsRoofFloor Actual standard 0.455*

Constable Terrace The building has a low energy consumption. It shows a significant saving on carbon dioxide emissions.

The Elizabeth Fry Building

Heater Diffuser Supply duct to hollow core slabs Two channel regenerative heat exchanger Floor Slabs Incoming Air Exhaust Air Filter Exhaust Air from rooms Principle of TermoDeck Operation Air is circulated through whole fabric of building Uses regenerative Heat Exchangers ~ 85% efficient

Quadruple Glazing Thick Insulation Air circulates through whole fabric of building Principle of Operation Mean Surface Temperature close to Air Temperature Heated using a single domestic heating boiler (24 kW) No heating needed at temperatures as cool as o C 87% of ventilation heat recovered In summer building is pre-cooled overnight Key Facts

Performance of Elizabeth Fry Building thermal comfort +28% User Satisfaction noise +26% lighting +25% air quality +36% A Low Energy Building is also a better place to work in ActualLow Energy Normal kg CO2/ m2 / yr Carbon Dioxide Emissions for Space and Water Heating

Performance of Elizabeth Fry Building Careful Monitoring and Analysis can reduce energy consumption

Termodeck construction Zuckerman Institute for Connective Environmental Research The ZICER Building 34 kW Photo Voltaic Array

ZICER Construction Ducts in floor slab

Performance of ZICER Building Initially performance was poor Performance improved with new Management Strategy EFry ZICER

Temperature of air and fabric in building varies little even on a day in summer (June 21 st – 22 nd 2005) Performance of ZICER Building

Construction of Low Energy Buildings Careful Monitoring of performance and adaptation where relevant Fuel efficient and alternative methods to provide energy Promoting awareness among occupants Tackling issues for reducing energy in existing buildings which are Grade 2 listed and of historic interest. Low Energy and Low Carbon Strategies at UEA

Engine Generator 36% Electricity GAS 61% Flue Losses 3% Radiation Losses 36% efficient Generation of Electricity with a Gas Engine

Engine Generator 36% Electricity 45% Heat GAS Engine heat Exchanger Exhaust Heat Exchanger 11% Flue Losses 3% Radiation Losses 81% efficient Combined Heat and Power at UEA Localised generation can make use of waste heat. Reduces conversion losses significantly

1997/98electricitygasoilTotal MWh Emission factorkg/kWh Carbon dioxideTonnes ElectricityHeat 1999/ 2000 Total site CHP generation exportimportboilersCHPoiltotal MWh Emission factor kg/kWh Carbon dioxide Tonnes Performance of CHP units Before installation After installation This represents a 33% saving in carbon dioxide

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

Condenser Evaporator Throttle Valve Heat rejected Heat extracted for cooling High Temperature High Pressure Low Temperature Low Pressure Heat from external source Absorber Desorber Heat Exchanger W ~ 0 Normal Air-conditioning 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 Compressor Adsorption Air-Conditioning

Legislation can help and hinder effective use of energy The method by which electricity is traded in the UK ( The BETTA System) has adversely affected viability of CHP in the UK. The European Union Emission Trading System has anomalies which hinder effective developments such as Adsorption Chilling. Building Regulations can hinder the building of most energy efficient buildings

Performance of Photo Voltaic Array 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 Peak output is 34 kW

Construction of Low Energy Buildings Careful Monitoring of performance and adaptation where relevant Fuel efficient and alternative methods to provide energy Promoting awareness among occupants Tackling issues for reducing energy in existing buildings which are Grade 2 listed and of historic interest. Low Energy and Low Carbon Strategies at UEA

Raising Awareness Each person in UK causes the emission of 9 tonnes of CO 2 each year. What do 9 tonnes of CO 2 look like? 5 hot air balloons China: 2.5 tonnes or 1.4 balloons

Comparison of emissions of different countries Raising Awareness

Computers do NOT switch off when using the soft SHUT DOWN. Typically they will waste 60 kg CO 2 a year. A Toyota Corolla (1400cc): 1 party balloon every 60m. 10 gms of carbon dioxide has an equivalent volume of 1 party balloon. Standby on electrical appliances 80 kWh a year balloons. A Mobile Phone charger: > 20 kWh per year ~ 1000 balloons each year.

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

An integrated approach to Energy Efficiency is needed. Technical – initial good design Effective management – up to 50% can be saved. Awareness on the part of the user. Up to 25% can be saved. Ventilation heating requirements are becoming a dominant issue in low energy buildings To achieve full potential of low energy buildings effective record keeping, analysis, and management is essential. Conclusions - 1 Effective design of low energy buildings will cost little more than conventional buildings.

Combined Heat and Power can be effective in reducing carbon emissions when GAS is available. Tri-generation should always be considered when there are significant summer or year long chilling requirements. Incorporation of renewable energy systems into buildings is attractive. However an integrated approach to generation and use in needed. Conclusions - 2 Promoting effective awareness can reduce energy consumption in low energy buildings dramatically. Ways to prevent back- sliding must be researched Some Regional, National, and International legislation is not conducive to promoting the most energy efficient strategies in communities.

Experience at the University of East Anglia Chongqing - 23rd September Low Energy Buildings and Low Carbon Strategies Keith Tovey ( ) M.A., PhD, CEng, MICE HSBC Director of Low Carbon Innovation: and Charlotte Turner: School of Environmental Sciences CRed