2 Carbon Reduction Strategies at the University of East Anglia Elizabeth Fry Building ZICER CHP Generation at UEA CRed Carbon Reduction 10 th May 2008 N.K. Tovey ( ) M.A, PhD, CEng, MICE, CEnv Н.К.Тови М.А., д-р технических наук Energy Science Director CRed Project HSBC Director of Low Carbon Innovation Recipient of James Watt Gold Medal 2007

3 Original buildings Teaching wall Library Student residences

4 Nelson Court Constable Terrace

5 Low Energy Educational Buildings Düşük Enerjili Eğitim Binaları Elizabeth Fry Building Elizabeth Fry Binası ZICER Nursing and Midwifery Hemşirelik ve Ebelik Okulu Medical School Tıp Fakültesi Binası Medical School Phase 2 Tıp Fakültesi Binası 2. Evre

6 The Elizabeth Fry Building 1994 Elizabeth Fry Binası 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 ~%20si. En son Bina Yönetmeliklerini bile büyük ölçüde aşmaktadır. Tek bir ev tipi merkezi ısıtma kazanı ile çalışmaktadır.

7 Conservation: management improvements – Careful Monitoring and Analysis can reduce energy consumption. thermal comfort +28% User Satisfaction noise +26% lighting +25% air quality +36% A Low Energy Building is also a better place to work in

8 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.

9 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 Structural Engineers: Whitby Bird

10 The ground floor open plan office The first floor open plan office The first floor cellular offices

11 Air enters the internal occupied space Return stale air is extracted from each floor Incoming air into the AHU Regenerative heat exchanger Filter Heater The air passes through hollow cores in the ceiling slabs The return air passes through the heat exchanger Out of the building Operation of the Main Building Mechanically ventilated that utilizes hollow core ceiling slabs as supply air ducts to the space Space for future chilling Recovers 87% of Ventilation Heat Requirement.

12 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 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

13 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 Pre-cools the air before entering the occupied space The concrete absorbs and stores the heat – like a radiator in reverse Summer day

14 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 The concrete slabs absorbs and store heat Heat is transferred to the air before entering the room Winter day

15 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 When the internal air temperature drops, heat stored in the concrete is emitted back into the room Winter night

The space heating consumption has reduced by 57% Good Management has reduced Energy Requirements

17 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 ZICER Building Photo shows only part of top Floor

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 Performance of PV cells on ZICER

21 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.

22 Use of PV generated energy 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

23 Actual Situation excluding Grant Actual Situation with Grant Discount rate 3%5%7%3%5%7% Unit energy cost per kWh (£) Avoided cost exc. the Grant Avoided Costs with Grant Discount rate 3%5%7%3%5%7% Unit energy cost per kWh (£) Grant was ~ £ out of a total of ~ £ Performance of PV cells on ZICER Cost of Generated Electricity

24 Engine Generator 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 61% Flue Losses 36% efficient

25 Conversion efficiency improvements 1997/98 electricitygas oilTotal MWh Emission factorkg/kWh Carbon dioxideTonnes ElectricityHeat 1999/ 2000 Total site CHP generation exportimportboilersCHPoiltotal MWh Emission factor kg/kWh CO 2 Tonnes Before installation After installation This represents a 33% saving in carbon dioxide

26 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

27 Conversion efficiency improvements 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 Chilling Compressor Adsorption Chilling 19

28 A 1 MW Adsorption chiller 1 MW Reduces electricity demand in summer Increases electricity generated locally Saves ~500 tonnes Carbon Dioxide annually Uses Waste Heat from CHP provides most of chilling requirements in summer CHP ~500

29 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?

30 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? Lao Tzu ( BC) Chinese Artist and Taoist philosopher "If you do not change direction, you may end up where you are heading."

31 WEBSITE cred-uk.org/ This presentation is available from tomorrow at above WEB Site: follow Academic Links Keith Tovey ( ) Energy Science Director HSBC Director of Low Carbon Innovation Carbon Reduction Strategies at the University of East Anglia