As part of the Retained Energy Management Services (REMS) that Low Carbon Europe (LCE ) provide Central North West London (CNWL), LCE are committed to assist CNWL in achieving 10% reductions in green-house gas emissions, displayed in carbon dioxide equivalent, through identifying energy efficiency opportunities. This case study focuses on just one of the Trust core buildings where there has been demonstrable identification, implementation and monitoring of energy efficiency savings.
The Woodfield buildings are used to provide outpatient and in-patient mental health care. The buildings are brick and mortar built with double glazing, approximately 15 years old. Considering the building’s age, the energy performance was considered poor with an Operational Rating of G on its 2013 Display Energy Certificate. There is a requirement for NHS bodies to achieve a specific energy consumption (SEC) target of 55-65 GJ/100m3. The overall performance at Woodfield during 13/14 was 67.18GJ/m3 and CO2e of 527.45 (T).
LCE undertook a full energy audit of the building reviewing; lighting, heating, refrigeration, ventilation, small power and opportunities to implement renewable technologies. LCE identified several projects that went on to be financed through the Department of Health energy efficiency funding. LCE secured around £500,000 on behalf of CNWL in the form of a non-repayable grant. The following energy efficiency projects were identified and implemented;
Chillers
Woodfield used approximately 359,599kWh of electricity per year, of which the chillers’ operation accounted for around 71,920kWh. By reducing operating hours to match that of building and increasing flow temperature set-points to 10°C, LCE saved approximately 11,000kWh or £1,100 per year.
Ventilation
The reduction of ventilation plant operation in combination with the modification of temperature set-points saved approximately 16,000kWh or £1,600 per year.
Boilers
LCE identified an opportunity to modify the time-schedules thus saving 150,000kWh of gas or £6,000 per year. Through modification of the primary heating circuit return water set-point from 75°C to 65°C, LCE realised a saving of 46,000kWh, or £1,800 of gas per year.
Lighting
LCE recommended the Trust replace fluorescent lighting with LEDs as well as integrate and install intelligent controls; this led to a saving of 90,000kWh, or £9,000 of electricity per year.
Renewables
LCE identified the opportunity for a PV panel installation of 13.5 kWp. With the Trusts’ commitment to source alternative, green fuels, they supported the PV business case and LCE assisted in project managing the implementation of the PV panels. The installation has supported a significant reduction in the electricity bills of the Trust.
Two years after LCE’s initial engagement, annual grid-electricity consumption has reduced by 31.02% and gas consumption 36.78%. Furthermore, the overall energy performance (GJ/m3) has also decreased by 35.64% and CO2e by 33.47%; these savings are considered particularly substantial considering these buildings were built in the 21st Century.
