Part L 2010: time to take control
Doug Robins explains why building-management systems will play an important role in achieving the proposed targets of the next stage of Part L — and other new legislation.
Government has given the construction industry something to think about over the summer months, with the launch of a consultation on changes to the current Parts L and F of the Building Regulations. It is a long document, and no doubt many are still considering its content.
However, one proposal stands out even at a first reading, and that is the proposed increase in required energy efficiency of buildings by 25% on Part L 2006 standards.
Under the current Part L, new non-domestic buildings must demonstrate (via the SBEM modelling software) a 25% improvement on a similar building constructed to 2002 standards. Part L 2010 would expect the same improvement, against 2006 standards.
One of the other proposals is that this target is aggregated. The thinking is that since different buildings have different energy requirements it could be more effective to require some buildings to achieve a less than 25% improvement — and others higher than 25%.
Whatever course of action is decided on, these energy-efficiency targets will be a major challenge for construction teams. Coupled with the added proposals that will be tougher on compliance issues, designers and clients will be looking for the most cost-effective ways to reduce energy use in their buildings.
There is no doubt that building-management systems (BMS) can offer a highly cost- effective solution to reduction of energy waste and will play a major role in achieving these targets. CIBSE Guide H, which deals with building-control systems, states that a control system can make major contributions to reducing energy waste, particularly in limiting heating and cooling to the minimum period necessary and prevention of unnecessary plant operation. The BMS also monitors and gives early warning of inefficient operation.
The Carbon Trust also states: ‘Poor control of heating, ventilation, cooling and lighting is responsible for excessive energy consumption in many buildings.’ In premises with well-controlled systems, heating bills can be 15% to 34% lower than in poorly controlled buildings. By the same token, inadequate or incorrect application of boiler control can easily add 15% to 30% to fuel consumption, when compared with a boiler which is properly controlled.
The Part L 2010 proposal document makes little mention of building controls or BMS, which is disappointing. The main methods for increasing energy efficiency outlined in the document are raising energy performance standards for the building fabric and increasing levels of insulation. But improvements in building fabric and in building services equipment are subject to the law of diminishing returns. At some point, not far down the road, the energy performance of a building will rely on the control of HVAC systems to achieve maximum energy efficiency and occupant comfort at all times.
One of the most important points that the proposed new Part L makes is that improving the energy performance of existing buildings is crucial if the UK is to meet its carbon-reduction targets and achieve security of energy supply. Again, building controls and BMSs can make a tremendous contribution to energy reduction in existing buildings, either by more effective use of existing control systems or with retrofitting of controls. The latter has become easier, with wireless technology enabling faster and more cost-effective installation.
Part L of the Building Regulations is largely influenced by development of the Energy Performance of Buildings Directive (EPBD), which is also currently under review and set for relaunch some time in 2010. The EPBD makes a clearer link between controls and energy efficiency in buildings, and a number of its requirements highlight the important role that controls play, for example, in monitoring long-term energy performance and identifying improvements.
And the EPBD is not the only other piece of legislation that will require better monitoring and management of energy in buildings. The Carbon Reduction Commitment will affect many organisations, which will need to rely on their BMS to keep track of energy use and help to cut waste.
In the 2008 Budget, the Government announced its ambition for all new non-domestic developments to be zero carbon by 2019. But it has acknowledged that simply adding renewables to buildings is not enough: ‘The balance between energy efficiency and renewables is an important issue. It is important that the CO2 goal is not achieved by applying excessive amounts of renewable energy provision to buildings with poor energy efficiency.’
Building-management systems can help to reduce energy waste, and achieve this balance in the long-term.
Doug Robbins is president of the Building Controls Industry Association.
