 The Energy Performance of Buildings Directive – a blessing in disguise?
June 01st 2005
The Energy Performance of Buildings Directive defines an approach for improving the energy performance of buildings across the EU, but not specific energy targets which are set by individual governments. It has to be transposed into UK law (and into all the other Member States’ legal systems) by 4 January 2006. This country’s targets are derived from the Kyoto commitment, the Government pledge of a 20% cut in CO2 emissions by 2010, the Climate Change Programme (currently under review) and the Energy White Paper The Directive applies to virtually all buildings (only those of less than 50m2 are exempt from its requirements). Overall the Government expects the performance of new buildings to improve by around 25%.
However, at the time of writing, some key decisions have not been finalised.
Does the UK need further regulation in this area? The short answer is ‘yes’. The performance of buildings has been improving slowly over the last 20 years but nowhere near fast enough to meet the climate change targets. Buildings account for around 48% of all emissions in the UK and the non-domestic sector for around 22%. Cost effective technology exists now to save around 20% of the energy currently used in buildings.
So will the directive be a boon or a burden to building owners, users and designers? There will obviously be some compliance costs, some new procedures and skills to learn. On the plus side, users will able to choose buildings of reduced operating cost and have every right to insist on specific levels of performance. These levers for change can be used to gain improvements which managers have been traditionally unable to insist upon, despite them being sound financial investments.
A key issue with all regulation is how it affects competitiveness. Studies by the Carbon Trust have shown that this directive will have no significant effect.
This matches our own assessment that, when capital and running costs are considered together, over 20% savings can be achieved with a payback of less than three years. However, this requires that more consideration be given to whole life costing.
The three key drivers for owners, users and designers will be: changes in the Building Regulations regarding energy performance (Part L); a requirement for energy certification; and regular inspection of boilers and airconditioning.
Part L The key change for new, non-domestic buildings in Part is that the energy performance of the building will be based on a carbon target for the whole structure. An initial target is calculated using the 2002 regulations to assess the CO2 emissions of a building of the same size, shape and use as the final building. This is then reduced by 15-20% depending on the type of services, and by a further 10% predicated on the possibility of using onsite renewable technology. For an air-conditioned building, for example, a 28% saving over current standards will be required. While renewable technology is included in generating the target, it does not have to feature in the design as long as the target is met. In practice, though, most designs will need to include at least 10% in order to meet the 28% saving.
Certain management techniques will have to be used to achieve the carbon savings. Automatic Monitoring and targeting (aM&T) and power factor correction both achieve a carbon reduction in the design – 5% and up to 2.5% respectively. We expect almost every building to include these features.
Most building services such as boilers, heating, hot water, air supplies, cooling, etc, operate for most of the time at part load – typically 15-20% – and seasonal differences also affect performance. Each major system will now have to meet part-load performance criteria.
For example boilers will be required to achieve at least at 80.8% system efficiency based on performance at 100%, 70% and 30% loads. Cooling system Coefficients of Performance (COP) will need to be above 2.25 based on loading at 25, 50, 75 and 100%.
The requirement for ventilation and air-conditioning fans to operate at 2 watts/litre/second at 25% load will effectively eliminate the typical damper-based solutions in favour of variable speed drives or variable pitch fans.
Energy performance certificates Energy performance certificates refer to both the intrinsic capability of the building (asset rating) and its operation in practice (operational rating) based on actual energy metered data. They will also include details of internal temperatures and of improvement measures. The rationale is that potential purchasers can make an informed decision about purchase or renting based upon the rating. This will be important to those considering running costs and those with an active CSR policy. The existence of the certificates should also create peer pressure to improve performance, just as in the white goods market.
We would expect the rating system to have an effect on asset and rent values, giving positive commercial advantage to those willing to provide energy efficient buildings.
Boiler and air-conditioning inspections The directive requires the setting up of inspection regimes for boilers and air-conditioning units over 12kW.
These would look at the efficiency of the overall systems and make recommendations regarding improvements.
As such, they are different to the regular safety inspections and would require different skills and measurements.
An alternative method, favoured by DEFRA (and, we understand, most other EU members) is to provide information on improving performance. However, governments must be able to show that this has an equal effect to the physical inspection regime.
This advice route is attractive because it does not require access to every boiler installation in the country. At its simplest, advice can be in the form of leaflets and manuals giving details of energy saving measures and better operational practice.
Another option being considered is for the boiler to be part of an automatic Monitoring and Targeting system; this would identify areas of energy waste from the energy consumption profile. A final decision on this issue is expected shortly.
Timetable The directive needs to be implemented in UK law by 4 January 2006; hence the imminent changes to the building regulations. Governments can delay implementation of energy certificates and inspections if they can show that there are not enough independent experts to carry out the work. To date the UK has not applied to take up this option. ESTA’s assessment is that a significant part of the required structures could be in place early in 2006. This is possible if the calculation methods are kept simple.
The directive requires that building standards are reviewed every five years so we can expect another review by 2011. The ODPM has already signalled that, in order to move towards the Government’s longer term goals, this is likely to require a further 25% improvement in energy performance.
Once the methodology of energy certification and its implementation are understood and operating, ESTA would like to see it made a standard management tool.
For example: one and three year plans could include targets for improvement in operational rating; operational certificates could be applied to every building over 1 000m2; and minimum standards could be set for existing buildings. More articles from ESTA: | 
