Many Local Authorities in the UK now require a report as part of a planning application to assess the energy demand of the proposed development and which then shows how a percentage of either this energy demand, or the associated carbon emissions, will be reduced through the installation and operation of on-site renewable/sustainable energy systems. This policy is often known as the ‘Merton Rule’ after the London Borough which pioneered this policy. The information, detail and percentage thresholds required in these reports varies between the local authorities and in this case, Runnymede District Council, implementing Surrey Structure Plan Policy SE2, required a 10% of annual energy use to be generated from on-site renewable/sustainable energy technologies, to be demonstrated through a standard report.
As is often the case when proposed developments seek planning approval, full details regarding building construction and specification were not available, however, building dimensions were and this allows ‘rule-of-thumb’ figures to be used to assess projected annual energy use and to break this down into component parts. From this, a picture of how and to what degree the various renewable/sustainability energy technologies can reach the 10% threshold can be established.
In this instance, heat pumps, either air source, or ground source were felt to be the best potential solution and these could also be connected to a cooling function, to further improve energy offset.
The Blewburton Partnership has over ten years of experience of working in the renewable/sustainable energy field and brings this to bear when producing this type of report.