Rapeseed Oil CHP helps BEST House Reduce Carbon Emissions
Bedfordshire East Schools Trust (BEST) is celebrating, following the completion of its brand new £2.2M low-carbon, Rapeseed oil-powered, co-location building, at the Samuel Whitbread Community College site in Shefford, Bedfordshire.
The project - which has been designed and constructed by the Stamford-based, low-carbon building specialist, LowC Communities Ltd - has achieved an Energy Performance Certificate (EPC) rating of ‘A’ and ‘Outstanding’ level under BREEAM’s energy guidelines.
Using an architectural design by Hanson Leddington Architects, the 805 square-metre building, named ‘BEST House’, is now home to a purpose-built nursery and a suite of offices for the delivery of children and family services via a number of public-sector partners.
Richard Griffin, LowC’s managing director, said: “From the outset, we aimed for outstanding energy performance from this building, and delivered it, with annual carbon emissions of less than 27Kg/m2. Although it was below the statutory threshold for compulsory BREEAM certification, we have worked to BREEAM’s ‘Outstanding’ level for energy and carbon credits – resulting in our client getting a high-efficiency building for a budget more suited to a traditional, less-efficient, new-build project.”
One of the key factors in the building’s performance was in the way that the load profiling was approached. The design team started with industry-standard modelling software, but then introduced a much more accurate process developed by LowC to determine the annual levels of energy consumption down to an hourly basis.
“This data enabled us to correctly size the generation technology to efficiently meet the needs of the building.” Griffin continued. “This level of accuracy is crucial to establishing operational performance. A building’s energy consumption can vary by as much as a factor of 200% depending on its occupants’ usage; and the associated electrical and thermal loads can also vary by up to 400% from the standard design tool modelling adopted through the traditional part L design approach.
“Even with energy-efficient technologies and insulation levels far in excess of the 2010 Building Regulations, it was clear that we needed to adopt a renewable energy technology to meet our own stringent performance targets in operation.”
The design team looked at all of the available options and, after careful evaluation, opted for an 8kWe, Pure Plant Oil combined heat and power (CHP) system, that would produce all of the renewable heat and power required – coupled to a thermal store to ensure renewable electricity could be generated when required without dumping heat.
Utilising locally-grown Rapeseed oil - an Ofgem-accredited renewable fuel with a carbon content of 0.009kg/kWh (2010 building regulations) - importantly, qualified the LowC Energy centre for double ROCS (Renewable obligation certificates) providing a revenue stream for the building’s owner, BEST.
Water use has also been minimised, by the building’s rain-harvesting roof collecting water and storing it in a tank to be used for toilet flushing.
Ian Kite, chief executive of BEST Ltd, said: “We are absolutely delighted with the new building and it will help us deliver our Trust’s aims of promoting the advancement of education and community cohesion.”
“The fact that construction started in May 2010, the nursery has moved in during January 2011 and the project is on time, within budget, and has overachieved its design commitments – is truly remarkable.”
“I couldn’t sing the team’s praises high enough as the process has been completely painless compared with the traditional construction routes previously adopted - so much so, that it’s almost unnerving!”