Let there be light

The new edition of Part L has placed yet more emphasis on designers, specifiers and installers to make office lighting solutions more energy efficient.

The more stringent regulations have presented challenges to lighters to improve energy efficiency by controlling energy usage whilst making sure occupants continue to enjoy optimum conditions for work.

The revised Part L specifies buildings other than dwellings require an improved average efficiency for the whole building of not less than 45 luminaire lumens/circuit Watt (lm/W), an increase from the previous 40 lm/W. This is a significant change, no longer allowing lighters the luxury of simply selecting a fitting from a list of high-efficacy lamps that meet the legal requirement.

Hugh King of Thorn Lighting says that, slowly but surely, the regulations are becoming more onerous: “The changes serve to illustrate that energy is one of the big drivers impacting on future lighting practice by contractors and product development by manufacturers. In the previous Part L, most lighters took the short cut by employing fittings from the given list of high efficacy lamps they knew wouldn’t fall foul of the requirements. That short cut has gone now, so you have to go through the calculations. Furthermore, there is no waiver for the first 500 W of installed lighting load.”

Bernard Pratley, technical manager of the Lighting Industry Federation says the new regulations shouldn’t be too much of a stretch for manufacturers: “The manufacturers are having to use more high-tech, better designed products, more high frequency ballasts, T5 lamps and the better optics that go with them, but they were geared up and already had the products there. When we were going through this re-write we said we could meet these extra requirements because we know we’ve got the products.”

King agrees that the new Part L should be tighter than its predecessors but warns that the regulations may not be wholly founded on lighting practice, more on the narrow-minded aim of driving down energy usage, in line with the government’s task of implementing the European Directive on Energy Performance in Buildings. “You can’t simply make all lighting decisions on a non-people basis,” he says. “Working conditions also have to be conducive for the occupants to perform efficiently and in comfort. People function better if the lighting is right.”

The refurbishment market presents contractors with huge opportunities to widen the use of new lighting technology, but Hagemeyer’s product marketing manager Gary Walker says this is the market that will prove slowest to adopt the changes: “As a wholesaler we’re always three or four years behind the technology in regards to the education of contractors, so we’ll have manufacturers coming to us with these new technologies but it takes a bit of time for the market to catch up. The slow down affects manufacturers’ ability to introduce more and more new products.”

Walker says further legislation that sets a timescale for old, non-compliant lamps and fittings to be replaced would help speed the process up. “Because there are still old lamps around, like a T12 tube, people don’t have to think about refitting, they can just put a new tube in. It would help if we had legislation that forced people to take out the old technology, the old control gear, and ensure that everything has to be replaced within, say, five years.

“It’s always this issue of the upfront cost of a refurbishment versus the long term energy saving. We’re trying to make people aware of those longer-term cost benefits of newer technology.”