Controls, commissioning and carbon commitments

23 March 2011

A group of lighting experts gathered in London to discuss the vital role of controls in cutting carbon emissions in commercial lighting.

Ben Cronin: Do you think that commercial landlords are conscious of the amount that can be saved on lighting?

Phil King: Well if they’re not conscious of it, it’s not for lack of trying. We regularly present at all sorts of different forums. We always draw the energy pyramid to show how passive design and good daylighting are key.

One thing I’ve drawn on some slides is the advantage of what I call the 15m rule - 15 metres glass-to-glass. Not only can you get good daylight in from both sides, you can naturally ventilate a space that’s two and a half times the depth compared to the height. So I wondered if in the future we’ll be having E-shaped and H-shaped buildings to respect the 15m rule. On the other hand you can’t let the tail wag the dog.

Jonathan Rush: I think that’s going to have to be necessary. It’s interesting talking about the tail wagging the dog because that’s exactly what’s happening with Part L. Basically it just says you have to make 25 per cent reduction against the notional building every time. What it needs then is people with design input to say, okay, within those confines, we are going to have to make a solution work.

Phil King: The thing that’s driving that if you’re delivering a Cat A office they expect it to be 300-500lux and that’s what we have to do. So we have to challenge those things.

Challenging Cat A

Ben Cronin: So how would you change that?

Peter McMunn: That’s one of the nubs of the problem in designing Cat A offices, that grid of lights. What else can one do, you don’t know who the end user is.

Peter McMunn: This country has ridiculous speculative office building. We are one of the only countries that build offices without thinking of the end user. In Germany they design buildings for end users. What a wonderful thing to do.

Jonathan Rush: And the 15m rule sounds very much like the German DIN standards. There’s a lot to learn from other people.

Ben Cronin: How often do you liaise with the end users and how often do they really get what they want?

Nick Brown: It doesn’t actually get round this problem, initially they want uniform lighting, even if they know at the design stage, which is rare, where the desks are going to go, they immediately say in a few years we will probably want to move them. I think the only way round it is to have lights that can move. That’s what we usually propose - a very low level ambient so you can get around the building and task lighting on the desks.

Mike Summers: Desk oriented lighting is coming back. I did it in the early 1980s.

Richard Forster: One of the things I find helps is if you stop thinking of lighting as a building service, it isn’t there for the building, it’s there for the people, if you talk about this it’s got to be related to the occupants of the building.

Jonathan Rush: A happily motivated person will work in most conditions. I have sat on my own in complete darkness working just from the glow of the screen, terrible for my eyes but I was quite happy and I think that’s one side that needs to be explored, user control.

Phil King: The thing about people being happy is all down to wellbeing. Now Breeam has 10 categories, energy being one and wellbeing is another. I think the message is getting over. The thing that’s changed message here is that 10 years ago we used to design a building and use Breeam to score it; now we use Breeam to inform.

Andrew Bissell: I think Breeam has been good for certain sectors but I think the fact you can just drop daylight without having to justify it to anyone is criminal. In the guides in schools, we have put daylight first and we have made the criteria really tough and we are going to get criticised for it but we’ve decided for learning environments, for health and wellbeing, daylight and sunlight have got to be there.

Scott Crease: That’s the way to use Breeam, it should be informed, a meeting, a discussion with the client of various aspects of how the building gets used and how in the end that benefits sustainability.

Jonathan Rush: This is the problem with all of these tickbox elements, if you look at the new Part L it says you get 10 per cent saving if you put in a daylight linking system, there’s very little to say how that’s working, whether it’s working properly, how it’s integrated, whether you’re actually making the benefits you thought it should do…

Andrew Bissell: We’ve got to drop this idea of daylight factors. Start using the sunlight and the daylight and the façade design so we can actually turn more lights off and people are happier within the space.

Commissioning controls

Ben Cronin: Do you think lighting controls are commissioned properly?

Arfon Davies: There are many buildings I’ve seen that haven’t been commissioned properly. It’s the norm more than anything. Who is to blame for that I’m not sure, but perhaps the responsibility should lie with the designer or lighting designer to see it through to the end.

Phil King: Breeam addresses that in a few ways: calls for an independent testing and commissioning specialist as opposed to just the contractor doing it.

Arfon Davies: Normally the contractor wants to get out of the job and lighting control is the last thing that happens, the place is furnished and fitted out, then you commission the lighting control.

Jonathan Rush: You need to build all of those systems in. For instance, you’ve got a big office, big windows, daylight sensors, blinds. The occupants come in in the morning, close the blinds, all the lights come on and they never get up, in this country we are terrible at fitting automatic blinds or external systems that automatically change with the weather.

Martin Preston: I think you do need to have automatic blinds but also the individual, the manual override, that’s what a lot of people don’t get. They go manual or they go automatic, but we have got to give them the override to suit them. The end-user is looking at productivity, and productivity is all about wellbeing. If you have a good chair, good lighting and so on, productivity goes up.

Ben Cronin: Do you engage with them enough to train them to use these things?

Bruce Griffin: What’s interesting is with the new post occupancy evaluation over three years. Who’s going to go back and do it? The obvious choice is the facilities guy for the client. With the NY Times building it took the engineer two and a half years to get it to the optimum efficiencies and that was 70 per cent savings at the end of the day.

Bruce Griffin: The reality is most of these buildings are overlit for individuals to start with. We are never going to get it right as designers, but we are doing the best possible.

Andrew Bissell: We have got that with an office in London. We said there’s 20 per cent more lights than they need, which is 20 per cent more lamps to change, 20 per cent more waste, 20 per cent more mercury, which you just don’t need to do. But you’re limited again as it’s the client’s perception that this is what we must have. It’s an educational thing. If you educate and explain to the client then they may go with it.

Arfon Davies: Education is a big issue. We deliver these very complex systems and two or three years down the line you’re gone and they don’t really know what to do.

Mike Summers: There is something coming out that I think could be quite good, which is compulsory display energy certificates. They were originally going to be compulsory but it was watered down. I think that’s really powerful, to have that certificate on the outside of your building.

FMs and lighting control

Ben Cronin: Do you think facilities managers understand lighting controls?

Jonathan Rush: No.

Nick Brown: They have often been let down by manufacturers or installers who do not commission properly. Several clients have said: “Look, I do not want any form of automatic lighting control, I’ve had a nightmare with it in the past, I want light switches.”

Martin Preston: We did a huge amount of research when we started looking into this suite of products we’ve launched. We spoke to a lot of people - consultant engineers, architects - and got feedback. One thing that came back was exactly what you said. They were sold the system, nobody looked after it, nobody commissioned it properly, nobody was there when the original facilities manager left. So we need the ability to go back and keep educating the right people.

Andrew Bissell: Clients have latched on to that. Clients are telling us we want you here four times to commission and we will pay you because we know the day the building is finished we will not see you again.

Scott Crease: I think education, being lectured to, that’s forum controls not the best way to learn. What you need is have some self-interest and motivation to do it and feedback.

Bruce Griffin: More organisations are actually appointing energy managers.

Bruce Griffin: Don’t you think that lighting control systems have just grown and mutated rather than taking a fresh look at what’s actually required. We did a lot of research and it came to light that the graphical user interface is critical.

Talking the talk

Ben Cronin: Is it important to get building management systems and lighting control systems to talk to each other?

Simon Barden: Requirements suggest integrating where integrating is useful, not just for the sake of integration.

Jonathan Rush: Intelligence in these systems is going to be important as well, look at patterns for instance, there will be a general pattern of what time people are leaving or coming into work.

Martin Preston: That’s the important thing. In a typical office building a huge amount of the controls should be predone - but you must have the ability for personal override.

Jonathan Rush: It’s about getting in at the beginning stages to be able to say “have you considered this and this”, and get it built into the cost plan and the expectation of the building.

The participants in the Lutron/Lighting controls forum were:

● Simon Barden, Arup
● Andrew Bissell, Cundall
● Nick Brown, Max Fordham
● Scott Crease, Max Fordham
● Arfon Davies, Arup
● Richard Forster, BSRIA
● Bruce Griffin, Lutron
● Phil King, Hilson Moran
● Peter McMunn, Siddell Gibson
● Martin Preston, Lutron
● Jonathan Rush, Hoare Lea
● Mike Summers, Arup