GLA Encourage Revised CO2 Emissions Factors in Energy Strategies

This week saw the release of updated guidance on how to prepare energy assessments by the GLA. The new document will replace the 2016 guidance from the beginning of next year and echoes some of the policy changes proposed as part of the Draft London Plan.

The update is notable as it encourages the use of SAP 10 carbon emissions factors. These factors assign an amount of carbon per unit of energy consumed or generated in a building. Factors in the new guidance reduce the calculated carbon emissions emitted by a unit of electricity by over half, compared to the SAP 2012 figures, reflecting changes in electricity generation in the UK.

This change to the guidance will impact on energy strategies by both:

  • improving the potential for electrical heat generation to meet planning targets, depending on the efficiencies of the system used; and
  • diminishing the carbon emissions offset by renewable electricity generation technologies such as combined heat and power (CHP) engines and photovoltaic panels;

The guidance has however, stopped short of adopting other changes included in SAP 10, these could of:

  • significantly impacted on the suitability of heat networks to meet planning targets, through increased distribution loss assumptions;
  • discouraged the use of a backstop thermal bridging heat losses, promoting detailed assessment of building element junctions; and
  • rewarded the development of a low energy lighting strategy.

Until an updated Part L is adopted by the government, expected later next year, these additional impacts included in SAP 10 will not require consideration by developments in London. However, design teams should give appropriate thought to these topics to develop buildings that are comfortable for occupants and minimise their actual energy consumption.

Greengage’s Energy and Carbon Management Team have extensive experience of preparing energy assessments for a range of developments including Clapham Park and Lansdowne Road.

Should you wish to discuss any of the issues raised within this email, require energy services or have any queries on its applicability for your development, please contact tom.gwilliam@greengage-env.com or call 0203 544 4000.