EVORA Global London Plan

London Plan: Generating your own electricity in London just became less attractive

The London Plan, which dictates all planning and development in the capital, is currently undergoing a major rewrite but many in the sector are unaware that some significant changes and adjustments have already come into force.

In October last year, the Greater London Authority (GLA) published updated Energy Assessment Guidance which applies from January this year and directly impacts on developers. All new planning submissions in London are now ‘encouraged’ to use the new emissions factors detailed in the government’s latest Standard Assessment Procedure for Building Regulations (known as SAP10) alongside PART L 2013.

This is a highly unusual step for GLA to have taken, given SAP10 has yet to be incorporated into official building regulations. The government is not due to consult on new Part L regulations until Spring this year so the new emissions factors are unlikely to be made law until the latter part of the year at the earliest.

However, the GLA guidance states that any energy assessments which do not use SAP10 will be expected to provide a justification as to why not and presumably this will be a consideration in planning approval.


The reason behind this policy change is England’s rapid decarbonisation of the National Grid which has seen the amount of electricity sourced from wind and solar technologies increase year on year, while at the same time there is a move away from coal fired generation to gas fired generation.

The GLA believe the new SAP10 factors more accurately reflect actual carbon emissions as the electricity emissions factor in SAP10 is now 55% lower than that specified in PART L 2013. As a result, generating electricity onsite, by using combined heat and power engines (CHP) and/or photovoltaic solar energy systems, are no longer as attractive to London planners as previously.

Additionally, district heat networks using gas-engine CHPs are unlikely to be favoured because of concerns about the impact on air quality, which has become a high-profile issue in London.

The guidance makes it clear that applicants will be expected to use other low carbon technologies such as heat pumps. Ground source heat pumps are generally deemed more efficient than air source heat pumps, depending on ground conditions.

In practical terms, any PART L 2013 compliance should be accompanied by a separate spreadsheet document, supplied by the Greater London Authority (GLA), that translates energy consumption to SAP10 carbon emissions.


The changes, detailed in the GLA’s Energy Assessment Guidance, affect both residential and non-residential applications referred to the Mayor of London from January this year including:

  • Developments of 150 residential units or more
  • Development over 30 metres in height (outside the City of London)
  • Development on Green Belt or Metropolitan Open Land

Applications for commercial developments also need to show at least a further 35% reduction in carbon emissions on top of those specified in PART L of Building Regulations 2013. However, the Mayor has already said that he intends to introduce zero carbon emissions for commercial developments in the final version of the London Plan which will be published later this year.

Domestic residential developments are already required to achieve zero carbon emissions. However, if this is not feasible or viable then developers must show how they will reduce emissions on-site by a minimum of 35% on top of those specified in Part L. The remainder of the target needs to be met via carbon-offsetting either elsewhere in London (for example photovoltaic panels on a local school) or by contributing a carbon offset payment.


EVORA EDGE can help the success of planning submissions in London by modelling and testing how such ambitious targets could be achieved using sophisticated, dynamic simulation software both for passive design (such as fabric improvements and shading strategies) and active design (mechanical systems and lighting).

If you would like to discuss further please email Erieta Dimitriou edimitriou@evoraglobal.com or call on 07538141399 for further information.