The route to Zero Carbon – Part 1
Every 3 years Part L of the building regulations ‘Conservation of Fuel and Power’ changes.
In 2006 the regulations improved over the previous 2002 level, with new dwellings roughly 20% better than previously. The SAP calculation methodology also got more involved. By 2010 the regulations tightened again, this time new dwellings improved by around 25% over 2006 levels (Again a new version of SAP came out with more data inputs and a more accurate reflection of the built dwelling). The 2013 regulations change is under consideration (consultations closed at the end of April for England; In October for Wales), with a few changes proposed and various options considered in the consultations for improvements beyond 2010 levels, with different proposals put forward for Wales then for England; Again with an aligned increase in complexity for SAP. For 2016, the Government’s target is ‘Zero carbon’ by 2016 for new dwellings – but what does that really mean?
The Scottish Building standards have also followed a similar theme, typically with targets set a little tighter than those for England and Wales. Northern Ireland have followed the England and Wales regulations levels albeit at a couple of years behind. Wales have now taken control of their own Building regulations and similar to Scotland, moving forward will set their own targets. The Welsh Assembly are committed to cut emissions by 40 per cent by 2020.
Ultimately, the UK along with the rest of Europe is moving towards an aim of ‘Zero Carbon’.
The actual timeline and target proposed overall is an 80% cut in greenhouse gas emissions by 2050, also a reduction in emissions of at least 34% by 2020 (both targets against a 1990 baseline). These targets are a legally binding framework set out in the Climate Change Act (2008).
The 2016 zero carbon target on the other hand is a commitment by the Government, but not a legally binding one, although it did have cross party support when it was made back in late 2006. The policy should contribute to the UK meeting its climate change goals and renewable energy commitment. It aims to reduce energy bills for consumers, promote innovation in low carbon technologies and benefit the long-term energy security of the UK. Zero carbon was initially equated to Code for Sustainable Homes Level 6 definition of Zero Carbon, which was to reduce regulated emissions by 100% and also to account for unregulated emissions from cooking and appliance usage. Following the March 2011 Budget, the zero carbon target was ‘watered down’ to regulated emissions only (i.e. the requirement to also compensate for cooking and appliances emissions was dropped).
The Zero Carbon Hub undertook considerable work advising Government as to how to achieve zero carbon for new dwellings. It was determined fairly early on that the ‘Code 6’ definition could not be made to work for all building types. The approach proposed was therefore a three level hierarchy of energy efficiency, “carbon compliance” and “allowable solutions” Carbon reduction in new buildings will be achieved using energy efficiency and carbon compliance measures until 2016, when allowable solutions will also be available to meet the ‘zero carbon’ targets.
We’ve gone from zero meaning zero, to something else.
2016 targets for the Energy Efficiency of new dwellings has been proposed as 39 kWh/m²per annum for apartments and mid terrace dwellings and 46 kWh/m² per annum for end terraced and detached dwellings. I think these targets could have been improved upon – the Welsh 2013 targets were at one point at least considering a step beyond these to a FEES+ level, although they dropped the idea of FEES (Fabric Energy Efficiency target) from the consultation proposals. The Passivhaus lobby and others have suggested a more stringent ‘Spec C’ requiring very low air tightness’s and Mechanical Ventilation with Heat Recovery in all new homes for the zero carbon target.
The recommendations at present for carbon compliance level for 2016, including on-site renewables are that the “built performance” emissions from new homes should not exceed:
- 10 kg CO2(eq) /m2/year for detached houses
- 11 kg CO2(eq) /m2/year for other houses
- 14 kg CO2(eq) /m2/year for low rise apartment blocks
Again, Carbon Compliance level does not seem too harsh.
Certainly in various parts of Europe, these kinds of levels are already being built to and exceeded.
The allowable solutions requirement on top of carbon compliance is still to be fully defined (The Zero carbon Hub again have produced a body of work covering a variety of options), but should via various means compensate for the remainder of emissions down to ‘zero carbon’. Allowable solutions does seem a little woolly. My personal feeling is that the level should be set such that builders need to seriously consider whether they would be better focusing on further on-site measures against the cost of allowable solutions. They should have to weigh up for themselves which is best for the particular circumstances of the site.
So that’s broadly where we’re heading to and also where we’ve been. Greenpeace have previously stated “climate change is already gripping the planet and (there is a need to) take urgent action to avoid catastrophic global warming”. There are also arguments about ensuring security of future energy supply and reducing demand, rising fuel prices and issues of addressing fuel poverty. Some developers are arguing for no changes in regulations, claiming that it will stifle building and therefore growth. At the same time, past messages have been ‘greenest government ever’ and that the government is committed to achieving cuts in carbon emissions.
But… there seems to be disagreement within Government as to whether the business case or the climate case has priority. Whether the 2016 aims are likely to be met (or go far enough) is open to debate. In a separate post, I’ll discuss the proposed 2013 waypoints in more depth.
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