Nearly zero energy buildings

The EU Directive on the energy performance of buildings was adopted in 2002. It was intended to improve the energy efficiency of buildings, reduce carbon emissions and reduce the impact of climate change.

A recast directive 2010/31/EU was adopted on 19 May 2010 to strengthen energy performance requirements and to clarify and streamline some of the provisions from the 2002 Directive.

The recast directive suggests that buildings account for 40% of total energy consumption in the European Union, and that as the sector expands, so will its energy consumption. In order to reduce the Union’s energy dependency and to honour its commitment to reduce overall greenhouse gas emissions by at least 20% below 1990 levels by 2020, it is necessary to reduce energy consumption in the building sector and to increase the proportion of energy from renewable sources. This will also help improve energy security.

A number of measures are set out to help achieve these objectives (see Energy Performance of Buildings Directive for more information).

Article 9 of the Directive requires member states ensure that:

• by 31 December 2020, all new buildings are nearly zero-energy buildings (nZEB).
• After 31 December 2018, new buildings occupied and owned by public authorities are nearly zero-energy buildings.

It requires that member states draw up national plans for increasing the number of nearly zero-energy buildings and develop policies and take measures to stimulate the transformation of buildings that are refurbished into nearly zero-energy building.

However, member states may decide not to apply the requirements in specific and justifiable cases where cost-benefit analysis over the economic lifecycle of a building is negative.

Article 2 of the Directive defines a nearly zero-energy building as ‘…a building that has a very high energy performance, as determined in accordance with Annex I. The nearly zero or very low amount of energy required should be covered to a very significant extent by energy from renewable sources, including energy from renewable sources produced on-site or nearby.’

Annex 1 lists the items that should be considered in calculating the energy performance of a building, such as the building fabric, heating and cooling, ventilation, lighting and so on as well as positive influences that may be considered such as solar systems, cogeneration, district heating, natural lighting and so on.

However, it does not define a specific standard of performance that might be considered ‘nearly zero’ and instead, says that national plans should include, ‘detailed application in practice of the definition of nearly zero-energy buildings, reflecting their national, regional or local conditions, and including a numerical indicator of primary energy use expressed in kWh/m2 per year….’

There had been considered to be some alignment between the requirement for nearly zero-energy buildings and the UK definition of zero-carbon homes and zero-carbon non domestic buildings. However, on 10 July 2015, the government published ‘Fixing the foundations: creating a more prosperous nation’ a plan for increasing Britain’s productivity. Amongst a great number of wide-ranging changes, the report stated, 'The government does not intend to proceed with the zero carbon Allowable Solutions carbon offsetting scheme, or the proposed 2016 increase in on-site energy efficiency standards, but will keep energy efficiency standards under review, recognising that existing measures to increase energy efficiency of new buildings should be allowed time to become established.'

This announcement was made with no consultation and came as a surprise to much of the industry. It is not clear where this leaves the UK in terms of plans to implement the requirements of the directive.

There was an attempt to revive zero carbon homes as the Housing and Planning Bill 2015 went through the House of Lords, however, following some political ping pong between the Lords and the Commons, the proposed amendment to the Bill was defeated.

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Comments

Does anyone know if this 'nearly zero' scheme has targets set in the UK?