Zero carbon homes: the good, the bad and the ugly

CSE’s Kieran dissects the consultation outcome

11 July 2014

I've been waiting very patiently (most of the time) for the outcome of the zero carbon homes consultation, which closed in October 2013.

The Government is aiming for new housing to be made zero carbon from 2016. Sometimes it won't be technically possible for developers to fully meet these standards on site. This consultation was an exercise to decide on a pragmatic, flexible way to help house builders meet the zero carbon homes standard though using 'Allowable Solutions', which permit them to reduce carbon emissions somewhere else (like retrofitting existing houses) and count this towards meeting their obligations.

The tumbleweed has rolled on by and now the consultation results are finally out! Here's a summary of the good, the bad and the ugly points.

The good

Most respondents to the consultation (43%) thought house builders should be required to invest Allowable Solutions within the locality of their development. Fingers crossed, the communities where new homes are built will benefit from funding for local carbon abatement projects. The continued mention of the ‘Code for Sustainable Homes’ also suggests the Government won’t be scrapping it just yet, though it will soon be voluntary for the majority of new homes – not mandatory in some local areas as it is now.

The outcome provides some clarity on the progression towards zero carbon homes:

  • On-site energy performance will be set at a level equivalent to Code for Sustainable Homes Level 4, representing a 20% improvement on current Building Regulations’ standards.
  • All four routes for delivering Allowable Solutions will be possible. This provides good variety, but all need further development to understand how they will work.
  • Allowable Solutions will help fund work to both residential and non-domestic buildings.
  • Local authorities will have a role to play in working with house builders to bring forwards Allowable Solutions projects, but this must be within the National Framework for Allowable Solutions – they cannot set local frameworks or delivery targets for Allowable Solutions specific to their area.

The bad

There still seem to be some unanswered questions. We need more answers and key decisions if we are to understand the true trajectory of zero carbon homes. For example:

  • Small sites will be excluded from achieving the same standards, but we don’t know what standards they will have to meet, or the definition of a small site.
  • The upper price limit of Allowable Solutions (per tonne of CO2 saving) requires further consultation; we are still no clearer on what this will be, or whether there will be a lower limit. Whilst most respondents (48%) supported a cost of £90/tonne, 70% of builders and developers opted for a much lower price of £30.
  • The types and locations of projects Allowable Solutions can fund remains unclear, including whether to limit them to England or the UK’s built environment, but is likely to include large carbon-trading projects under the EU ETS scheme.
  • The process of matching house builders with projects (‘brokerage’) has yet to be decided. I’m sure suggestions to use the ECO brokerage system as a starting point will worry those of you who’ve had experience of ECO.

The ugly

The most worrying remark I read in the document was that “30 years of residual carbon emissions was suggested as the [Allowable Solutions] time period for two reasons: 30 years is broadly representative of the lifetime of onsite technologies and the period beyond which the electricity grid will be substantially decarbonised”.

I hope this is a misunderstanding of facts. I rather hope that building fabric improvements have lifetimes far beyond 30 years, and that we actually decarbonise our electricity grid by 2030 – as the Committee on Climate Change recommends.

Would you still call a new house 'zero carbon' after its 30 years are up? And would you call it 'zero carbon' if everything we plug into our new home is causing additional emissions?

If we can get these issues sorted out, then perhaps we will finally reach a new frontier of zero carbon house building.

You can read the consultation outcomes for yourself here on the Government's website.

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