SE1: Develop an area-wide minimum low or zero carbon energy target for new development

Description and rationale for policy objective

The objective of this policy is to set out for the local authority area as a whole a target percentage of the energy to be used in new development to come from decentralised and renewable energy or low carbon energy sources where it is viable. Although the Climate Change PPS talks about a target in terms of the percentage of energy, in practice most local authorities are expressing the target in terms of a percentage carbon reduction.

This type of target was originally pioneered by the London Borough of Merton, although there are now many examples that have been used by other local authorities and in regional spatial strategies. The policy RE5 in the draft South West RSS is an example (correct as of March 2010) – see the pages on Policy Context for more information.

Some key differences between the original 'Merton' type policies and the approach suggested in the Climate Change PPS are that:

  • Any targets should be for low and zero carbon (LZC) energy sources, i.e. not just renewable energy
  • The targets should not just be for “on-site” energy options, but should include “near site”, that is they should allow the possibility that any target could be met by connecting the development to a source of low carbon heat that may be outside the boundary of the development site, e.g. to an existing district heating network

You should be aware that the use of this sort of target may have now been made largely redundant by the proposed trajectory of future Building Regulations towards zero carbon, which came out after the Climate Change PPS. This is particularly the case for LDDs that are in the early stages of their development, and won’t be fully adopted until 2012 or 2013. See Policy Context pages for more detail.

A key distinction between the use of this sort of policy and the Building Regulations is that the latter requires a carbon reduction, but leaves it to developers to decide whether that is achieved through the use of energy efficiency, or LZC energy, or both. In practice, however, the Regulations will require significant quantities of LZC energy to be used in any case if the future carbon reduction requirements are to be met.

Paragraph 20: Planning authorities should expect a proportion of the energy supply of new development to be secured from decentralised and renewable or low-carbon energy sources

Paragraph 26: Planning authorities should have an evidence-based understanding of the local feasibility and potential for renewable and low-carbon technologies, including microgeneration, to supply new development in their area. This may require them, working closely with industry and drawing in other appropriate expertise, to make their own assessments.

Drawing from this evidence-base, and ensuring consistency with housing and economic objectives, planning authorities should:
26(i) set out a target percentage of the energy to be used in new development to come from decentralised and renewable or low-carbon energy sources where it is viable. The target should avoid prescription on technologies and be flexible in how carbon savings from local energy supplies are to be secured;
26(iii) set out the type and size of development to which the target will be applied; and
26(iv) ensure there is a clear rationale for the target and it is properly tested.

Paragraph 29: Well-founded development area and site-specific targets drawn up in line with this PPS may expect significant proportions of the energy supply of new development to be secured from decentralised and renewable or low-carbon energy sources

The SW Regional Spatial Strategy

REVision 2020. See section 6, in the main report and annex 7: on-site generation, which is in turn taken from the London Renewables Toolkit. This shows the technical feasibility and potential additional build costs of achieving different carbon reduction targets from the use of on-site renewable. Note that the carbon reduction targets and percentages considered in this analysis are on the basis of total predicted carbon emissions (regulated plus unregulated).

A later piece of work was carried out in support of the draft RSS policies for zero carbon development (what was Policy G). This is available from the Additional Technical Work Section of the RSS page on the SW Councils website, under “5.Carbon neutral / zero carbon development study”. This considers the additional build costs for achieving different levels of carbon reduction for three scales of new housing development as well as three classes on new non-residential development. Note that the carbon reduction targets and percentages considered in this analysis are on the basis of regulated carbon emissions only, and not total emissions.

This work also includes an analysis of the feasibility and viability of targets for small scale housing developments (10 or less dwellings) both on and off mains gas.

UK Government zero carbon consultations and impact assessments

The UK Government consultation on a definition for Zero Carbon New Homes and Non-Domestic buildings. The consultation document issued in December 2008 includes, in Annex E, a useful summary of the additional build cost of different technology options to achieve different levels of carbon reduction. The document does not consider in any detail the viability of targets for non-domestic buildings. This consultation is supported by two Impact Assessment reports prepared by Cyril Sweett and Faber Maunsell which you can refer to for more detailed information on the modelling. These documents are:

Costs and Benefits of Alternative Definitions of Zero Carbon Homes: Project report Published 26 February 2009

This updated an earlier research report by the same team, entitled: Research to Assess the Cost and Benefits of the Government's Proposals to Reduce the Carbon Footprint of New Housing Development, September 2008. This research provided information to underpin the full Regulatory Impact Assessment published alongside the Building a Green Future Policy Statement on 23 July 2007.

UK Government consultation on 2010 Part L

See Table 21 in Proposals for amending Part L and Part F of the Building Regulations – Consultation, Volume 1, June 2009. This sets out in Table 21, in the right hand column, indicative additional capital costs for achieving a 25% reduction in regulated emissions for a variety of non-domestic buildings. This does not identify whether the savings are achieved by energy efficiency alone, or the use of LZC energy options, or both. You should not use the data for the domestic sector, as the emissions savings are based on changing the way that emissions savings are calculating and the impact of insulating party walls. This means that the cost assumptions do not assume the use of any LZC energy technologies and therefore do not provide a guide as to the cost impact of an LZC policy.