Explanation of Nearly Zero-Energy Buildings (NZEB’s)

Buildings are central to the EU’s energy efficiency policy, as nearly 40% of final energy consumption and 36% of greenhouse gas emissions are in houses, offices, shops and other buildings. Improving the energy performance of Europe’s building stock is crucial, not only to achieve the EU’s 2020 targets but also to meet the longer term objectives of our climate strategy as laid down in the low carbon economy roadmap for 2050.

Therefore, in 2010 the EU issued a Directive 2010/31/EU Article 9(1) on the energy performance of buildings (EPBD) as the main legislative instrument at EU level for improving the energy efficiency of European buildings. A key element of the EPBD, especially for achieving these longer term objectives, is its requirements regarding Nearly Zero-Energy Buildings (NZEB’s).

Article 9(1) of the EPBD requires Member States to ‘’ensure that:

a) By 31 December 2020, all new buildings are nearly zero-energy buildings.
b) After 31 December 2018, new buildings occupied and owned by public authorities are nearly zero-energy buildings.’’

Under this Directive, it also states that Member States must draw up national plans for increasing the number of NZEB’s. It also states that Member States must develop policies and take measures such as setting of targets in order to stimulate the transformation of buildings that are refurbished into NZEB’s. How these were to be developed was left to each Member State.

Each Member State was left to develop their national plan but should include the following elements:

a) Definition of the Member State’s detailed application in practice of the definition of NZEB’s, reflecting their national, regional or local conditions. More importantly, a numerical indicator of primary energy use expressed in KWh/m2 per year. This would then allow the EU to compare each Member States target heating/cooling demand for buildings.

b) Intermediate Targets for improving the energy performance of new buildings by 2015, with a view to all new buildings being NZEB’s after December 2020.

c) Various other information regarding financial or other measures for the promotion of NZEB’s, including details of energy from renewable sources in new buildings etc.

On the basis of these national plans, the EU Commission is required to publish a report on the progress of Member States starting December 2012 and every three years thereafter.

Only eight Member States hit the target for 2012, one of which was the UK.

The UK submitted their national plan by September 2012 and the UK Government set a target for all new homes in England to be zero carbon from 2016 and an ambition for all new non-domestic buildings in England to be zero carbon by 2019. This was to be achieved by increasing the fabric performance of the buildings with a U-value of 0.15 W/m2/K or less. This would allow the target energy requirements of their buildings to be set at 45 KWh/m2 per year. This was to be assisted by renewable and low carbon technologies, together with carbon off-sets, as an allowable solution.

Portugal released their national plan under Decree Law No 118/2013 in August 2013 and set intermediate targets for improving energy efficiency before 2015, so as to set out the roadmap for 2018 and 2020. However, their national plan did not indicate the targets for KWh/m2 per year.

By October 2014, 26 of the 28 Member States had submitted their national plans apart from Spain and Greece. We await the next progress report from the EU.

The table below gives us an indication between the current UK building regulations and the Portuguese targets for thermal insulation indicated from their last report to the EU, as follows on table 1.

The UK values for the above are nearly equal to Passivhaus design which complies with the principles of high energy performance of the building fabric. Passivhaus design is the benchmark for ‘Extreme Fabric’ design to achieve a zero carbon/energy rated building.

In the meantime, the current targets being stipulated in the Algarve are almost three times less efficient than the current UK building regulation values.

However, we can offer specialist advise on meeting NZEB’s targets in the Sustainable Superstore by assisting in the design of the following on table 2.

We incorporate the local traditional construction materials and improve on the construction techniques, as well as introducing hi-tech solutions to achieve the targets of NZEB’s.

In addition, we offer Project Management services to ensure that these measures are incorporated in the design stages and are implemented during construction stages.

The cost of incorporating these initial design measures into your home will be recuperated over time by significantly reducing your energy bills.

By Kevin Conroy
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Kevin Conroy is partner of the Sustainable Superstore and owner of MPB Services, offering Insulation Solutions, Construction and Project Management. 915 239 933
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