Last reviewed 27 December 2017

Light-emitting diode (LED) lighting has been touted as the technology that can slice energy bills. However, its ability to mimic natural daylight also opens up other possibilities for wellbeing and health. Laura King takes a look.

The Carbon Trust estimates that lighting consumes around 20% of the electricity used in commercial buildings; by extension it will almost certainly account for a significant chunk of a company’s energy bill. LEDs provide a relatively easy way to reduce these costs by offering energy savings of around 20% for fluorescent and high-intensity discharge lighting, and up to 85% for halogen lighting. A further boon for the environment is that, unlike florescent lights, they do not contain mercury that has to be specially disposed of.

LEDs are part of the solid-state lighting family and use semi-conductors to convert electricity into light. As the light is generated within the semi-conductors, this offers additional benefits as they are much sturdier than traditional lighting. Furthermore, their functionality is not dependant on climate, meaning that they will continue to work in difficult environments.

Durable, dependent, less toxic and with cheaper running costs, another bonus of using LED technology is its lifespan. LEDs are generally expected to last 50,000 hours, although some LEDs report operational lifespans of up to 100,000 hours. At 50,000 hours a light used for 10 hours a day, 7 days a week will last nearly 14 years.

Historically, one downside to installing LED lighting was the initial capital cost. However, with the price of components decreasing and the market growing, the technology is becoming increasingly affordable. Although high-end LEDs are still comparatively expensive, they will still offer a relatively quick return on investment when the whole life costs of the technology are taken into consideration.

LEDs also used to have a reputation for creating a stark light that could be quite uncomfortable. This too is a thing of the past. Advances now mean the LEDs come in a variety of brightness levels, with options for dimming, colour temperatures and width of beam. There is now an LED for almost any purpose.

As a tried and tested solution to high energy and maintenance bills, LED lighting is likely to be high up on most facilities manager’s wish list when cost-cutting. However, in the last few years, the technology has also entered the field of wellbeing. Called human-centric, biodynamic or circadian lighting, LED technology is now demonstrating that it can offer much more than pure financial savings.

Human-centric lighting

From an evolutionary perspective, we are still getting used to spending a large part of our day working indoors. Furthermore, although electric lighting, electricity and technological advancement has improved our productivity and ability to work well beyond sundown, it has also meant that many of us spend up to 90% of our time indoors under artificial light as well as a significant amount of time staring at screens.

Much has been written about the impact of all this light. Light sets our natural body clock — our circadian rhythm — regulating our cycles of sleep, appetite, immune responses and mood. The wrong light at the wrong time can put us out of sync and as a result our bodies suffer. Most noticeably, our ability to sleep is impaired due to the impact of light — particularly within the blue wavelengths — on melatonin, a hormone that influences sleep cycles. However, the harm can run much deeper, with research linking exposure to light at night to certain types of cancer, obesity, heart disease and depression.

At the other end of the scale, blue light at the right time has been shown to boost concentration, reaction times and mood. Indeed, exposure to bright light within the blue spectrum during the day has been shown to help — rather than hinder — sleep at night.

With this in mind, LED lighting could present a solution. As a digital light source it is inherently “tuneable” and with this has come the ability to bring nature indoors by imitating wavelengths from nature’s daily light cycle from sunrise through to sunset.

It is a convincing argument, and evidence is mounting to show a strong correlation between the colour of light and the state of a person — for example how alert or relaxed they are. Some forward-thinking schools are using the research to help students concentrate, and in hospitals, lighting that matches circadian rhythms has been used to help patients rest and recover.

As yet there are no definitive answers as to how much human-centric lighting can improve productivity in an office environment, and there are still many unanswered questions. However, some have likened human-centric lighting to the provision of other wellbeing benefits. At the very least it improves people’s perception of a workplace, and is likely to help promote happier and healthier employees — all of which can be done with a technology that has been proven to save money over its lifetime.

LED upgrades

LED lighting certainly has a lot of potential, and although the research behind the technology will continue to broaden, the following should be considered in any lighting project.

Solving a problem

What does the lighting need to achieve? Is it all about energy saving, reductions in maintenance regimes or improving lighting conditions? Although there may be an over-arching strategy, this should be refined for individual spaces as there will be different factors in play for different areas. For example, in a retail environment, high-quality light is important on the shop floor, but this is unlikely to be needed in the warehouse.

To understand the needs of the building, an audit can be done to see what the current lighting provision is, as well as how it is used. This includes understanding and prioritising what expectations are in terms of light levels, maintenance and energy efficiency.

Good design and good technology

A badly lit space is very obvious. A well-lit space, less so. A good lighting designer or reputable supplier can help develop plans into a lighting solution that will work well for all elements of the project.

This can include providing advice on the best type of LED technology and fittings to use, options for retrofitting, as well as use of task lighting, lighting accents and lighting controls. They can also provide advice on the quality of the fittings, certification, verification of data and warranties.

Designers should incorporate daylight into their schemes as much as possible and offer solutions that provide a balance between natural and artificial light. Lighting should be controllable and layered so that there is a mix of general lighting as well as personalised lighting. This will mean that the design can be tuned to suit the needs of occupants.

Thinking outside the box

Fundamentally, it should be remembered that human-centric lighting is designed to help emulate the natural cycle of the sun and reconnect people with nature. As well as creating something akin to daylight inside, employees should be reminded of the benefits of getting outside, as well as winding down in the evening by not using electronic devices that emit blue light. Encouraging staff to go for a walk at lunchtime could very well offer some of the same benefits.