The proposed new SAP calculation is intended to allow assessment of the effects of the Future Homes Consultation proposed options. One of the headline-grabbing proposals in SAP 10.1 is the proposed carbon factor for electricity at 0.136 – this will mean ground source heat pumps have carbon factors of 0.030 – 0.045 compared to a gas boiler at 0.23. That’s a saving of more than 80% in carbon emissions just by switching heating to ground source heat pumps.
With lots of councils across the country declaring climate emergencies, many of which commit to carbon-neutral targets ahead of the UK’s 2050 ambition, a growing number of new-build developments are already embracing the low-carbon approach.
In adherence to the Committee for Climate Change’s recommendation that homes should make use of low-carbon sources of heating, in particular electrically-powered heat pumps that produce no point-of-use emissions, and the new National Design Guide, which singles out ground source heat pumps and district heating systems as recommended heating technology, Bristol is witness to a number of new-build schemes utilising this ultra-low carbon, non-air polluting, and low-cost heating solution to support its 2030 carbon-neutral pledge.
50 affordable homes are being constructed at Shaldon Road in Bristol to Passivhaus standards by United Living in partnership with United Communities and the Bristol Community Land Trust. The energy-efficient ‘self-finish’ properties will each feature a mini Kensa Shoebox ground source heat pump connected to an ambient shared ground loop array. Complementing the low-carbon ground source heat pumps will be an MVHR system and solar PV panels. The homes will be constructed using a thermally -efficient, single-skin Porotherm block. A green transport plan and protected green corridor harmonise the projects’ environmental credentials.
The push by local planning authorities to place energy efficiency and carbon-saving requirements on buildings that go beyond the requirements of the national Building Regulations is resulting in some ground-breaking ultra-low carbon, energy-efficient developments. Notably:
1: Bristol City Council requires developers to reduce CO2 emissions by 20% and to follow a heat hierarchy that encourages renewable and low-carbon heating.
2: The Greater London Authority requires developers to reduce CO2 emissions for new developments by 35% (10% must be from fabric improvements) compared to current Building Regulations.
The Future Homes Standard consultation proposes reductions of 20% (option 1) or 31% (option 2) in CO2 emissions for all new dwellings. However, it is also consulting on whether to remove the ability for local planning departments to impose deeper reductions via the planning process. This threatens the planning process being a major influence to impact CO2 emissions and achieve the UK’s zero-carbon targets.
The London Energy Transformation Initiative (LETI) comments “local authorities will lose the ability to meet their climate emergency zero-carbon commitments if they are stripped of their powers to go above and beyond the new Part L”. Whilst the Future Homes Standard offers many significant highlights, the lowlight of lower carbon compliance targets is troubling. Kensa has addressed this in its response to the consultation.