A burning issue

I

The Code for Sustainable Homes needs to catch up with new lighting technologies,

writes Robin Morris

nvestment in lighting is an essential ingredient for creating energy efficiency and reducing fuel poverty. Yet, despite being the third-largest consumer of energy in the home, lighting is often overlooked.

“White LEDs are poised to take over the majority of lighting tasks in the next five to 10 years”

At a recent retrofitting conference organised by the National Housing Federation, it was argued that investment in low-energy lighting can be more cost-effective than loft insulation. The independent energy assessors’ body National Energy Services found that, in a sample dwelling, moving from 30 per cent to 100 per cent low-energy lamps effectively reduces that dwelling’s emission rate by around seven per cent. LED (Light Emitting Diode) lighting can double that saving. But the Code for Sustainable Homes (CSH) needs to catch up, as its modelling tool, SAP, does not recognise new lighting solutions. Indeed, the national body that stimulates innovation, the Technology Strategy Board (TSB), had to develop its own extension spreadsheet to SAP to account for upgraded lighting measures during its own Retrofit for the Future competition. However, the CHS does reward the provision of dedicated low-energy light fittings. The definition was introduced by Building Regulations, and, at that time, implied compact fluorescent lamps (CFLs). Initially, the code awarded 1.2 points for at least 40 per cent of fittings dedicated to low-energy light fixtures, and 2.4 points for at least 75 per cent. In May 2009, the description was streamlined to give one and two points respectively for these same minimum proportions. Although regarded by some as a box-ticking measure, it

helps the code maintain focus on energy consumption from domestic lighting. But, with the phase-out of incandescent lamps, the definition of dedicated energy-efficient fittings is being lost from the Building Regulations that underpin the code. In a move that is to be welcomed, the 2010 code will reward the whole contribution that efficient lighting makes to reducing dwelling emission rates. However, this cannot be properly represented in the modelling tool, SAP 2005, and even the 2009 SAP revision does not cater adequately for lighting. Currently relying on the light-source lumens per

watt measure, introduction of standard illumination efficacy comparisons (W/sq m/100lux) would bring a marked improvement to SAP. The Energy Efficiency Partnership for Homes is looking at LENI, or Lighting Energy Numerical Indicator (the calculation method for annual lighting consumption), BS EN 15193, as a more

20

CIBSE Journal June 2010

meaningful way to recognise the most energy-efficient lighting systems, rather than look at the light emitter’s lumens per watt, which is a rather crude yardstick. Unfortunately, the Department for Environment,

Food and Rural Affairs (Defra) Market Transformation Programme, which helped to create the market for CFLs in the UK, and the EU Energy Related Products Directive, expect banned incandescent lamps will be replaced either by CFLs, creating an 80 per cent saving, or halogen lamps, resulting in a 30 per cent improvement. But this restriction to two types of low-energy lamp shows a lack of ambition for further cost-effective energy savings when better alternatives are already available.

There is a plethora of new and emerging technologies

that promise radical cuts in energy, although many are not ready for use today. For example, electrode-less fluorescent lights offer efficiencies similar to conventional tubes, but these are recommended as suitable for large spaces in non-domestic settings. Metal halide lights are only used for high brightness applications and get very hot. Electron stimulated luminescence lamps aim to replicate incandescent reflector lamps, but are still in development. Also under development are lamps that use thin-film, doped silicon oxide emitters of red, green and blue light, in place of the traditional tungsten filament, although details of projected performance are scant and prototypes not expected until next year. OLEDs (organic light-emitting diodes) are still in the early stages of development too, although absolute levels of light output and lifetime still need to be addressed. Micro-plasma panels are similar to plasma television screens, and light panels could be developed to exceed 100

Used fluorescent lamps are classified as hazardous waste by the Environment Agency.

www.cibsejournal.com Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24