Current regulations for low energy lighting in buildings focus on luminaire efficiency. The Society of Light and Lighting (SLL) has been applying pressure on the government to move to systems-based targets in the next revision of Part L.
In this month’s issue of Lux, Iain Carlile wrote: ‘Part L is correct in its requirement to reduce energy consumption, but the metrics used for lighting are quite crude and predominantly only cover the efficacy of the luminaire – not the total energy consumption of the lighting system.’
Current legislation, which focusses on luminaires, would allow for a building to run off far more energy efficient lights than necessary and never switch them off.
Martin Valentine, a lighting expert at Municipality of Abu Dhabi City – and once part of the AECOM team putting together Part L – told Lux that Part L is ‘based mostly on the efficiency of lighting fixtures only — which is great — but overall load wasn’t really catered for.
‘There’s not enough coverage of controls. They weren’t really promoted enough. But they’re common and not expensive these days.’
Controls can reduce energy by 60-80 per cent in buildings, both commercial and domestic. Valentine said: ‘Maybe 60-80 is in extreme circumstances, but you could reach 50-60 per cent reductions easily, just by installing controls.’
Absence controls in commercial properties would be the difference between lights remaining on for days or even weeks, without anyone noticing and lights only being used when someone needs to see.
‘Light switches are not necessary anymore,’ he continued. ‘I think controls are essential.
‘Part L is affecting the rest of the world. I’ve been implementing those ideas in Abu Dhabi, but it’s just one part.
‘We need to be looking at controls and overall limits as well as luminaire efficiency. But we also need to not lose sight of light quality. The four things work hand in hand.’
Valentine warned that the danger with complicated legislation is that nobody really knows what is going on. He believes Part L is a good thing but needs to move with the times, rather be caught behind.
He said: ‘It needs to evolve and it needs to be clear cut. People need to know what’s going on and benchmarks need to be in place.’