Strutt & Parker Positive Energy

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1 Strutt & Parker Positive Energy November 15 Resources & Energy The Bower at Stockley Park Energy Costs Report Strutt & Parker Resources & Energy 20, Gracechurch Street London EC3V 0BG Contents 1.0 Introduction Building Performance Comparison with Existing Offices Financial Comparison with Existing Offices Commentary 4 Appendix A 5 Appendix B 6 Resources & Energy The Bower at Stockley Park November 15 1

2 1.0 Introduction The Bower Building is an energy efficient new office development which is presently in the early stages of construction. The pre-construction design and energy evaluation has achieved an Energy Performance Certificate (EPC) rating of a high B. The actual EPC score is 27 which is two away from achieving an A rating and in addition the design and construction is aiming to achieve a BREEAM Excellent score. 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 3m³/(h.m²) 70% better than 2010 Part L regulations (unchanged from 2006 regulations). Energy generation from Solar PV panels VRF heat recovery air-conditioning system. Heat recovery ventilation (HRV), saving energy and reducing heating costs. 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 zone controlled and LED s are used throughout the building. The figures in this report are based on the Pre-construction EPC assessment (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 (ECG019) Energy Use in Offices. The document provides Typical and Good Practice energy use, cost and carbon emission benchmarks for office buildings in the UK. 2.0 Building Performance Comparison with Existing Offices Figure 1 shows the data from Table 1 and compares energy use on a per square feet basis 2 at the Bower to a Typical and Good Practice Office Building CIBSE Typical Office Building CIBSE Good Practice Office Building Bower 0 Heating + Hot Water Figure 1- Annual kilowatt hour energy consumption per sq.ft The Bower significantly outperforms both the Typical and Good Practice Office Buildings for energy consumption with significant improvements across most energy use categories Floor area taken from EPC total useful floor area 3 CIBSE and EPC figures converted from m 2 to sq.ft using a conversion factor of sq.ft per m 2. 4 Subject to CIBSE building model Cooling Auxilliary Lighting Equipment Total Resources & Energy Energy Costs Report November 15 2

3 The Typical Office Building can be likened to office stock constructed in the 1990 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 2006 and The Bower makes an improvement over Part L2A 2013 of 27% 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 10w/m 2 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. 3.0 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 2. This assumes an energy price of 4.51p/kWh gas and 10.82p/kWh for electricity 6. Figure 2- Financial comparison 5 EPC Benchmark rating B (Score 37) if Newly Built 6 Pricing from DECC Commercial Energy User Pricing 2015; 2 nd Quarter Average Resources & Energy Energy Costs Report November 15 3

4 4.0 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 is targeting a BREEAM excellent rating with the assessment taking into account the high performance systems specified. The BREEAM excellent rating will be 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 2 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 rising energy prices predicted for the coming decade and beyond coupled with increasing demands for environmental responsibility, the benefits of leasing an energy efficient building will only increase over time. Energy prices have experienced peaks and troughs in recent months due to artificially low oil prices, however they will continue to steadily rise 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. Resources & Energy Energy Costs Report November 15 4

5 Appendix A The Bower Building Energy Performance Certificate Resources & Energy Energy Costs Report November 15 5

6 Appendix B The Bower Building Technical Data Sheet Resources & Energy Energy Costs Report November 15 6