Strutt & Parker Positive Energy

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1 Strutt & Parker Positive Energy December 16 Resources & Energy The Bower at Stockley Park Energy Costs Report Contents 1. Introduction. Building Performance Comparison with Existing Offices 3. Financial Comparison with Existing Offices 3 Strutt & Parker Energy The Bower at Stockley Park December Commentary 4 1

2 1. Introduction The Bower Building is an energy efficient new office development which has just been completed. The pre-construction design and energy evaluation predicted an Energy Performance Certificate (EPC) rating of a high B, however the actual construction has achieved an impressive A rating. The actual EPC score is 1 and the post construction BREEAM submission has targeted an Excellent rating with a score of 8.65%. Some of the features which give the building this rating are as follows 1 : Highly insulated external fabric with high performance glazing to reduce heat loss. Solar shading on external facades Air tightness rating 3.4m³/(h.m²) 7% better than 1 Part L regulations (unchanged from 6 regulations). Electrical energy generation from 37m² Solar PV panels VRF heat recovery air-conditioning system. Low NOx high efficiency gas boilers Heat recovery ventilation (HRV), saving energy and reducing heating costs. Natural ventilation solution for reception and atrium areas Low water consumption with dual flush WCs, aerating low flow taps, low flow showers and sensor activated low flush urinals. High level of sub-metering and zoned temperature control. Good natural day lighting to reduce use of artificial lighting. Artificial lighting is occupancy and daylight controlled and LED s are used throughout the building. The figures in this report are based on the Post-construction EPC certificate (Appendix A) and the BRUKL Output Document (Appendix B). They are compared with the Typical Office Building as defined in the Chartered Institute for Building Services Engineers (CIBSE) Energy Efficiency in Buildings (ECG19) Energy Use in Offices. The document provides Typical and Good Practice energy use, cost and carbon emission benchmarks for office buildings in the UK.. Building Performance Comparison with Existing Offices Figure 1 shows the data from Table 1 and compares energy use on a per square feet basis at the Bower to a Typical and Good Practice Office Building CIBSE Typical Office Building CIBSE Good Practice Office Building Bower Figure 1- Annual kilowatt hour energy consumption per sq.ft 1 Floor area taken from EPC total useful floor area 3 CIBSE and EPC figures converted from m to sq.ft using a conversion factor of sq.ft per m. The Bower Energy Costs Report December 16

3 The Bower significantly outperforms both the Typical and Good Practice Office Buildings for energy consumption with significant improvements across most energy use categories 4. The Typical Office Building can be likened to office stock constructed in the 199 s prior to the introduction of Part L of the building regulations. The Good Practice office building is broadly equivalent to office buildings built between 6 and 1. The Bower makes an improvement over Part LA 13 of 43% 5. Table 1- End Use Energy Consumption Summary Table Building Heating & HW kwh/sq.ft/.year Cooling Auxiliary Lighting Equipment* Total Typical UK Office Good Practice UK Office The Bower * Equipment includes items such as computers, servers and printers which are not part of the design specification of the building. They are estimated based upon typical usage related to office buildings in the EPC modelling software. Energy used by equipment does not count towards the total for emissions calculations. Good practise design lists electrical design load for small power as 1w/m however, The Bower has an electrical design load higher than this. This is the reasoning for the higher than good practise value seen under the equipment heading and is common for new buildings due to the ever increasing use of technology by occupants. The design value is notional and will be entirely under the control of the occupant as it relates to IT equipment, mobile device chargers and other small electrical items. 3. Financial Comparison with Existing Offices The financial benefit realised from lower energy consumption per sq.ft when occupying The Bower compared to occupying a Typical Office Building of the same type is shown in Figure. This assumes an energy price of 4.46p/kWh gas and 1.7p/kWh for electricity 6. 4 Subject to CIBSE building model 5 EPC Benchmark rating B (Score 37) if Newly Built 6 Pricing from DBEIS Commercial Energy User Pricing 16; nd Quarter Average The Bower Energy Costs Report December 16 3

4 Figure - Financial comparison 4. Commentary Compared to the CIBSE Typical and Good Practice Office stock benchmarks, The Bower Building performs exceptionally well on energy use across all categories of fixed energy consumption. The total figures represent The Bower as being two times better performing than good practice and three times better than the typical office building. The Bower design and construction has achieved a BREEAM excellent rating with the assessment taking into account the high performance systems specified. The BREEAM excellent rating is an indicator that The Bower is an energy efficient building and will offer a high level of comfort to its occupants. As mentioned in Section the energy associated with Equipment is higher than the Typical value however this is entirely notional. Equipment energy consumption will depend on the occupant s use of technology and the function of the space and therefore more technology intensive occupants will have higher Equipment energy values. With energy prices being somewhat unpredictable in recent years, coupled with increasing demands for environmental responsibility, the benefits of leasing an energy efficient building will only increase over time. Energy price security is key for successful business and having the ability to record and demonstrate mandatory carbon reporting and CSR targets is both important and cost efficient. Energy prices have experienced peaks and troughs in recent months due to artificially low oil prices, however they have begun to rise as predicted and The Bower offers a hedge against this. Energy policy is now focused on commercial buildings (Minimum Energy Efficiency Standards and ESOS) and occupants will experience more regulation in respect of their individual energy use. The Government are in consultation now to Reform the business energy efficiency tax landscape with the aim to introduce mandatory energy reduction targets and/or carbon tax penalties. Occupying an energy efficient building like The Bower limits the risks imposed by these regulations which are aimed at more inefficient buildings. The Bower Energy Costs Report December 16 4

5 Energy Performance Certificate Non-Domestic Building 4, Roundwood Avenue Stockley Park UXBRIDGE UB11 1AF Certificate Reference Number: This certificate shows the energy rating of this building. It indicates the energy efficiency of the building fabric and the heating, ventilation, cooling and lighting systems. The rating is compared to two benchmarks for this type of building: one appropriate for new buildings and one appropriate for existing buildings. There is more advice on how to interpret this information on the Government's website Energy Performance Asset Rating Technical Information Main heating fuel: Natural Gas Building environment: Air Conditioning Total useful floor area (m ): Building complexity (NOS level): 5 Building emission rate (kgco /m ): 1.99 Benchmarks Buildings similar to this one could have ratings as follows: If newly built If typical of the existing stock Green Deal Information The Green Deal will be available from later this year. To find out more about how the Green Deal can make your property cheaper to run, please call

6 Technical Data Sheet ( vs. Notional Building) Building Global Parameters Area [m ] External area [m ] Weather LON 3 Infiltration [m 5Pa] 3 Average conductance [W/K] Average U-value [W/m K].33 Alpha value* [%] 1.3 Notional LON 5 1 * Percentage of the building's average heat transfer coefficient which is due to thermal bridging Building Use % Area Building Type A1/A Retail/Financial and Professional services A3/A4/A5 Restaurants and Cafes/Drinking Est./Takeaways 1 B1 Offices and Workshop businesses B to B7 General Industrial and Special Industrial Groups B8 Storage or Distribution C1 Hotels C Residential Inst.: Hospitals and Care Homes C Residential Inst.: Residential schools C Residential Inst.: Universities and colleges CA Secure Residential Inst. Residential spaces D1 Non-residential Inst.: Community/Day Centre D1 Non-residential Inst.: Libraries, Museums, and Galleries D1 Non-residential Inst.: Education D1 Non-residential Inst.: Primary Health Care Building D1 Non-residential Inst.: Crown and County Courts D General Assembly and Leisure, Night Clubs and Theatres Others: Passenger terminals Others: Emergency services Others: Miscellaneous 4hr activities Others: Car Parks 4 hrs Others - Stand alone utility block Energy Consumption by End Use [kwh/m ] Heating Cooling Auxiliary Lighting Hot water Equipment* TOTAL** Notional * Energy used by equipment does not count towards the total for calculating emissions. ** Total is net of any electrical energy displaced by CHP generators, if applicable. Energy Production by Technology [kwh/m ] Photovoltaic systems Wind turbines CHP generators Solar thermal systems 3.97 Notional Energy & CO Emissions Summary Heating + cooling demand [MJ/m ] Primary energy* [kwh/m ] Total emissions [kg/m ] Indicative Target * Primary energy is net of any electrical energy displaced by CHP generators, if applicable. Page 8 of 1