Guiding regulations

26 September 2011

Following our launch of the Lighting Systems Legislation Campaign last month more organisations have come on board to lend their support. Lighting looks at how the debate has developed since September

The International Association of Lighting Designers (IALD) has become the latest organisation to back moves for a more systems-based approach to lighting regulation in the UK and the use of the lighting energy numeric indicator (LENI) to calculate energy consumption.

The move by the US-based organisation to back Lighting’s campaign and similar initiatives by bodies under the umbrella of the Lighting Liaison Group, call on the UK government to take into account ‘used’ rather than ‘installed’ load and the effective use of controls when revising Part L of the Building Regulations. “The IALD strongly believes that so-called ‘energy’ metrics that only use luminaire efficiency or connected load are inadequate to meet today’s needs,” says Kevin Theobald, president elect of the IALD.

“We globally support efforts to save lighting energy by means of metrics, such as LENI, that reflect actual usage and encourage the use of daylighting, controls and electric lights to meet building users’ varying needs.”

Feedback

Lighting launched the campaign in the last issue and has obtained initial feedback from the government, with a civil servant pointing out that the ways in which Part L, the simplified building energy model (SBEM) and LENI handled lighting calculations for new-build and large extensions were very similar.

We put this point to three of the people we quoted in our last article: Peter Raynham, president of the Society of Light and Lighting; Liz Peck, director of LPA Lighting; and Mike Simpson, technical and design director at Philips Lighting.

In a joint response, they said: “We accept that LENI is included in the SBEM whole building energy assessment calculation but not as a separate item. SBEM also assumes uniform lighting across the working plane and doesn’t take account of the task or ambient solution, which will deliver further savings in used energy. It also assumes full control for daylight and occupancy, which isn’t required in the lighting section, so [it] may not give accurate results.

“What we are seeking is for LENI to be brought out as the main calculation for the lighting part of a building’s energy load. It can then be put back into SBEM as part of the whole building energy calculation.”

The civil servant in question also argued that LENI may not be a practical solution for smaller projects and could discriminate against smaller electrical contractors. Alan Tulla, managing director of Alan Tulla Lighting, is a strong advocate of LENI but admits to some sympathy with the regulators here.

“The big advantage of minimum efficiency targets for lamps and luminaires is that performance is very easily verifiable. My one worry about LENI is that there are so many variables. I can see the appeal of something as simple as luminaire lumens per circuit watt.”

Iain Macrae, head of global lighting application management at Thorn Lighting and president elect of the Society of Light and Lighting, admits it would be unrealistic to recalculate an entire room when replacing a couple of light fittings. “There is a benefit there for having a simple performance number like luminaire lumens per circuit watt, but to put it to 75 really limits people’s choices,” he says.

“It’s not beyond the wit of the industry to come up with a simple Q&A spreadsheet or web page, which asks contractors to fill in the boxes for the size of the room and the hours of use and to have some standard figures on how much an office runs at daytime and night-time and then to pull off some performance information from our database and get a LENI figure. The industry can make it simple for people who don’t understand or haven’t got the resources to do it themselves.”

Looking overseas for standards

Kevan Shaw, design director at KSLD, professional member of the Professional Lighting Designers’ Association (PLDA), and its recently retired director of sustainability, disagrees that such efforts may be beyond the scope of some electrical contractors.

“In respect of LENI, the basic method of calculation set out is not particularly onerous,” he says. “It is a lot less complex than proper cable sizing and circuit-breaker selection. It is ridiculous to lose the power and effectiveness of mandating design to a LENI benchmark, for the sake of small-scale projects.”

Models from abroad can also provide some pointers for a more effective system than the one currently being suggested.

James Benya, principal at Benya Lighting Design in Portland, Oregon, suggests California’s Title 24 and the ASHRAE/IES 90.1-2010 codes are both useful foundations for adoption, while Macrae says the European Energy Performance of Buildings Directive gives designers more flexibility in how they approach an overall installation.

Fred Bass, managing director at Neonlite International, which owns the Megaman brand, adds: “International standards need to define minimum standards within each discipline of building services to make sure really inefficient equipment is not used.

“They also need, however, to define overall maximum consumption in such a way that design freedom is given back to the professional specifier. With a broad approach, I can foresee international agreements that will allow local variation. A more inclusive approach is vital.”

Proposals for amending Part L and Part F of the Building Regulations’ are scheduled for publication by the UK government in December 2011. To influence the debate and to stay up to date with developments, join the ‘Lighting Discussions’ LinkedIn group.