EPBD in Wales
Wales route to NZEB
On the 31st December 2011 the Welsh Government were granted devolved powers to set their own Building Regulations standards independently from the UK Government. Both would still need to meet the mandate of the EU Recast Energy Performance of Buildings Directive (EPBD), which will require all new buildings to be ‘near zero energy buildings’ (NZEB) by 2020. However, this new law allowed Wales to be able to set their own strategy and standards for the implementation of the NZEB targets.
Since the devolvement of Regulatory powers for Wales did not happen as quickly as anticipated, Wales has made less progress towards setting out their routemap towards NZEBs than England. In lieu of a routemap for Wales at this time, currently the industry is assuming the requirements are likely to be similar to those set out in England.
Zero Carbon/ NZEB requirements for England
The Zero Carbon Hub have helped the UK Government derive a definition and policy for zero carbon homes that would be flexible and practical to deliver. There are therefore three components to meeting the new standard:
- The Fabric Energy Efficiency Standard (FEES) , which represents the overall energy demand of the building and reflects its intrinsic energy performance as a result of its insulation levels and airtightness, etc. (Measured as ‘primary energy use per m2/ year’, similar to the standard used in Passivhaus – kWh/m2y)
- The Carbon Compliance Standard (CCS) , which reflects the efficiency of the delivery of heating, hot water and lighting and will include a contribution from on-site renewable energy generation. (Measured as an absolute limit on the as-built CO2 emissions per m2/ year.)
- Allowable Solutions , which will include a range of potential additional measures, mostly comprising off-site solutions, to deliver any shortfall from the above actions in delivering a net zero carbon dwelling. This third requirement may also be met by ‘over performing’ on the requirements of the FEES and CCS. The Passivhaus approach to building fabric performance combined with renewable energy systems (RES) should be a viable mechanism for delivering this goal.
The contribution that each of these three factors must make towards achieving the overall zero carbon target is still to be finalised, but the ZCH recommend:
- The FEES limit for the building fabric should be set at 39 kWh/m2y for mid terrace houses and apartments and 46 kwh/m2y for all other housing, including end terrace, semi detached and detached dwellings. This reflects the inherent efficiency of form of each dwelling type and acknowledges that it is more difficult and less cost effective to achieve such low energy use on buildings with more exposed surfaces.
- The CCS limit looks likely to be set at 10 kg CO2(eq)/m2y for detached houses, 11 kg CO2(eq)/m2y for attached houses and 14 kg CO2(eq)/m2y for low rise apartment blocks.
- A consultation on the exact structure of Allowable Solutions, though believed to include options to invest in near- or off-site carbon saving projects, in energy refurbishment, district heating initiatives, or other carbon saving schemes, particularly that will bring a wider community benefit.
Now Wales has devolved control of the energy performance of buildings, the policies and methods to deliver NZEBs over coming years are likely to follow similar principles in some areas to the English initiatives above, but vary in others. There is therefore still potential that Welsh Government will aim for a stronger fabric first approach, then subsidised by RES (as proposed in PassREg).
However, Welsh Government have recently issued a statement (March 2014) indicating that they will not be aspiring to meet the NZEB targets earlier than required by the EPBD. It requires that all new public buildings will need to be NZEB by 2019 with all other buildings from 2021.
The UK Government has placed a strong focus on the refurbishment of existing buildings and has set up the ‘Green Deal’ initiative to help fund refurbishment measures. However, the targets set are essentially those to be ‘deemed cost effective’ (based on a simple payback within 15-20 years) rather than ultra-low energy. The intention is to encourage the wide scale modest refurbishment of a large number of buildings, rather than a very low energy refurbishment of fewer buildings. Unfortunately, many retrofit measures do not currently appear cost effective under the scheme, although new subsidies are being introduced to encourage their uptake.
Subsidies exist to encourage new renewable energy sources; the Feed in tariff for electricity generating systems and the Renewable Heat Incentive for heat generating systems. There are requirements for existing buildings to meet a minimum fabric energy performance standard before they are eligible for the full rate of the subsidy for renewable energy systems, though this is not a very low energy standard (only EPC rating of C or above).