Halving energy use in buildings – Report for GCB
The Department for Business, Energy & Industrial Strategy (BEIS) asked the Green Construction Board to respond to the 2030 Buildings Energy Mission. We worked with Julie Godefroy Sustainability to produce the background report, published and available here.
Together, we reframed the brief and based our work on data and evidence from buildings which have already achieved a 50% reduction in energy consumption. We can learn a lot from these buildings. There are recurring approaches, techniques and systems that are responsible for their excellent energy efficiency. We consider these the ingredients of the ‘low energy building recipe’.
Recurring features of a low energy building
The key features common to case study buildings were that they:
- Set a contractual energy performance target
- Predicted future energy use at the design stage and during construction, therefore not relying on compliance calculations
- Optimised the form to reduce energy use and minimise capital costs
- Adopted a ”Fabric first” approach with a very energy efficient envelope
- Provided openings for a passive ventilation strategy in summer and Mechanical Ventilation with Heat Recovery (MVHR) for winter
- Had low total energy consumption with consideration of all energy uses (not just the uses currently covered by Building Regulations)
- Included energy performance quality assurance during construction and comprehensive commissioning
- Included aftercare to deliver low energy consumption in operation. With mechanisms for performance monitoring and evaluation integrated at design stage and followed-through during operation
Lack of reliable publicly available data
Alongside some fantastic examples of buildings working well, the search highlighted the limited amount of reliable, publicly available data on actual energy use in buildings. This is an issue in itself. Despite efforts to improve monitoring information there is still a need to significantly improve the approach to building energy data disclosure and analysis. There is a great potential for digital innovation in this area.
Achieving more than 50% reduction is already possible
The power of even a small amount of data is shown by the case studies used here. This report demonstrates that achieving at least a 50% reduction in the energy use of all types of new buildings is technically and financially feasible now. If we are to create the Zero Carbon future outlined by the latest Committee on Climate Change report, we should follow the example set by these buildings.
We are very grateful to Lynne Sullivan (Green Construction Board and Chair of Buildings Energy Mission Task group) and Jane Thornback (Construction Products Association) for their trust and input into this report. And we also want to thank the clients, architects and design teams, contractors and occupants of all 15 case studies selected: their work demonstrates that delivering buildings which are so energy efficient is possible.