The London Plan switches to SAP 10 - will this end CHP dominance in the capital?
21 Nov 2018
The GLA’s changes – coming into force in January – are set to end CHP dominance in the capital. Jon Ponting from the Energist Technical Team explains why.
The Greater London Authority (GLA) has surprised many in the construction industry by announcing changes to the London Plan; starting this January.
The seemingly small adjustments will change how developers invest in heating systems on large projects, and without so much as a fanfare to announce these changes, many could be caught out by this policy change.
Meanwhile, the London Plan is currently going through a major rewrite, which isn’t due to go live until the end of 2019 or later.
These latest announcements apply to the current London Plan which means sites currently getting ready to go into planning will need to follow the new guidance. It’s primarily focused on ‘referable’ schemes (which is the bigger housing developments), however the changes are being encouraged on smaller sites also.
The big change is the adoption of SAP10 emission factors. This will significantly change the result of the SAP and SBEM models which are used in planning strategies.
To unpack what this means we need to rewind to 2012, and the launch of the current Approved Document Part L. This building regulation requires all new homes and businesses to meet a strict Target Emission Rate, based on how much energy is needed for heating, hot water, ventilation and lighting.
The energy use is multiplied by the emission factors of relevant fuel types used (gas, oil, electric, wood) to create the Building Emission Rate. The higher the emission factor of a fuel, the higher emission rate a dwelling will have.
In 2012, the emission factor of electricity was 2.5x higher than gas. This was because of the UK’s reliance on coal power stations.
Six years on and we still use the same set of Building Regulations, which means we still use these emission factors.
In reality, the CO2 associated with the National Grid has plummeted. Every year we are breaking records for energy produced by wind and solar technology, which means the emission factor of electricity is much lower than what Building Regulations suggests.
Earlier this year, the BRE released a draft revision of the SAP calculator. In it, the emission factors were updated, and electricity was shown to no longer be the fly in the ointment. However, with no confirmed date for Part L to change, these emission factors have been left to sit on the shelf.
The GLA has taken the unprecedented move of asking for all new planning submissions to use SAP10 emission factors for calculating energy use, while still using the rest of the current SAP2012 methodology.
Under this adjustment, the use of electricity on site will provide much lower CO2 readings, which means electric heating systems will be more viable than before.
The GLA is still keen to promote District Heating Networks (DHN), but this change means gas is no longer the only contender.
Greener electricity won’t just change the way we assess heating options in our buildings – it also means generating your own energy on site won’t result in as big a carbon offset as we see currently. That could discourage developers from systems such as PV and CHP.
With such a significant change coming into force so quickly, it makes sense to work with a team who are on top of the changes, who commit to your deadlines, and who are ready with the answers.
The Energist Planning Team is on hand to do just that, with a new-look Energy Strategy which fully complies with these London Plan changes.