By Leslie Thomas,

Lighting Technology Manager at Fagerhult 

LEDs are efficient, but a fifth of the UK’s electricity still goes to lighting, so our net zero goals won’t be met without action in that area. Light fittings, like any other manufactured product, also need to be made and transported. Leslie Thomas, Lighting Technology Manager at Fagerhult UK, discusses how we can make and use lights sustainably.

Awareness and regulation are encouraging more artificial light not less

Workspace lighting is tightly regulated. Traditionally, those rules focussed on task lighting, which primarily meant assessing the amount of light falling on a work surface. But, light affects us in other ways too. Brightly lit spaces can create a sense of wellbeing, with regulation increasingly encouraging more and more light around us in work environments.

Light is also central to our ability to sleep well. Humans have a circadian rhythm, a biological clock that makes us feel wakeful at certain points in the 24-hour cycle, and sleepy at others. But we also experience circadian entrainment – clock adjustment in response to stimuli such as bright morning light. Even quite powerful artificial lights give us much less Illuminance than life under a big blue sky, perhaps not enough to work as an alertness trigger. Standards such as the WELL certification for healthy buildings require bright morning light, because this ensures both daytime alertness and evening drowsiness.

Regulation is also capturing the fact that developed-world workers are an ageing population, with older eyes needing more light. Meanwhile, many developing countries are expecting developed-world levels of light.

So how do we limit artificial light?

The result is a world that generates more and more light, but knows it should be doing the opposite. What can be done? The answer is smarter control of our lighting, using each artificial light only as needed.

If daylight sensors assess how much light is coming in the window, a smart system that knows how much is required overall can adjust minute to minute, dimming or deactivating fittings where the need is already being met. More light is going to be present nearer that window, so these systems must work per luminaire, not per room. Architects and others must play their part also, harvesting that precious resource, daylight.

Many spaces now have presence detectors, so lighting switches off automatically when it would be wasted. Subtler systems go further, assessing for example which desks in the room are occupied, and adjusting so that light levels fall off, away from each worker.

Material matters

Right now, most of the carbon cost of a light comes from electricity. But, for those using renewable energy, the majority of the footprint is materials. This matters, because we are all heading to that world. How can we cap the impact of lights as physical objects?

There isn’t a single answer, but some choices are more sustainable than others. Multilume Re:Think is a lightweight unit made entirely from hardened cardboard. Discovery is a plastic fitting, with around 30% of the plastics made by fossil free plastics. With a wooden frame and recycled reflectors from discarded TVs, Kvisten is 77% made up of recycled or renewable materials.

Fagerhult also has an initiative called Re:Furbish. Send along one old light fitting, even one we didn’t create, and we’ll assess what we could do with it. A typical case would see LED strips replacing fluorescent tubes in the same housing.

Lighting makes our lives better and more productive. With commitment and smarter systems, we can enjoy the benefits of that sustainably.