Let there be light

The extra hours of daylight gained as we swing into summertime will undoubtedly be lifting spirits from Land’s End to Loch Ness. But it will also gladden the hearts of a growing number of convenience retailers who are successfully harnessing the natural power of daylight to keep their energy bills low and create better store environments in which to browse, spend, and work. And as we’ll go on to demonstrate, there are many different ways of putting this natural power to good use.

Solar panels are probably the first to spring to mind. Contrary to popular belief, modern-day solar panels take in daylight for power generation and do not need direct sunlight to work. They will function on rainy, overcast days, although they are at their most effective on clear, bright days.

There are two main types of solar panels: photovoltaics (PV) which convert the sun’s energy into electricity and solar thermal, which use the sun’s energy to heat water.

And the good news for retailers contemplating solar panels is that the outlay isn’t what it used to be. The cost of installation has fallen steadily as demand has increased, with a significant reduction in 2012, and more falls predicted in 2013/14.

“Just like chiller doors, the cost of green energy, and solar panels in particular, is coming down all the time,” says retailer Jonathan James who owns two Budgens stores and leases four forecourts in Cambridgeshire. “They can still represent quite a hefty upfront cost, though, if you don’t qualify for green financing such as the Green Deal. Their appearance is also improving. I’ve seen some which are disguised as roof slates,” he adds.

A 50% grant from the Low Carbon Trust helped the community-run Lodsworth Larder in West Sussex to install 14 large solar photovoltaic panels back in 2010 at a cost of £20,000. Just over three years later it’s close to having achieved payback, thanks to savings on its energy bills and an additional revenue stream, as director Martin Lester explains.

The panels provide almost all of the store’s lighting needs and contribute towards the running of the chillers. However, thanks to the government’s Feed In Tariff, it also receives an income of just over £1,000 a year from its energy supplier. The tariff sees businesses, and homes, paid for the electricity that they generate. How much you are paid depends on the size of your system, but the lowest rate homes and small businesses will be paid is 21p per kilowatt hour (kWh) of electricity they generate. (To give you an idea, one kWh will allow you to boil 10 kettles for two minutes).

In addition to this ‘generation tariff’, you can also benefit from an ‘export tariff’ of 4.5p per kWh for selling any electricity that you generate but don’t use back to the national grid.

“We’ve had the system for three years now and in that time have generated just over 5,200 kWh,” Martin explains. “We have some rather large trees at the back of the store which block some of the sunlight,” explains Martin. “If they weren’t there we’d probably be getting about £2,500 a year.”

Chartman Stores director Clive Sheppard is another solar panel convert after having spent £100,000 installing solar PV panels at five of his eight forecourts in the South-West of England.

“Installation wasn’t a problem, and the benefits are manifold,” he says. “The first is that by generating your own electricity you can keep a handle on your energy bills. The fact that you generate a second income stream via the Feed In Tariff is also another great benefit, and then there is the environmental side. Using electricity generated by natural resources means my carbon footprint is kept low. I believe that shoppers will care much more about this, and I’ll be looking to communicate my sustainable credentials to shoppers,” he says.

“The big misconception is that the technology is not reliable. It’s come on leaps and bounds in the past couple of years alone and we’ve had no glitches,” he adds.

Natural light

Another way to reduce your energy bills is by slashing your reliance on electrical lighting and instead let more natural light in.

In Wells, Somerset, large glass panels in the forecourt canopy of the Symonds Budgens not only give it a softer look, but also filter natural light, thus reducing the need for electric lighting.

The addition of natural light can also have a dramatic impact on mood, motivation and productivity. A recent study by US firm Pennsylvania Power & Light reported that after completing building upgrades to use more daylight, staff absenteeism rates dropped 25%, productivity increased 13.2% and energy costs declined 69%.

It can also have an incredible impact on retail sales. The old, but regularly quoted, 1999 Pacific Gas & Electric Company study examined a chain of 108 retail stores where two-thirds of the stores were fitted with skylights and one-third were not. Incredibly, the study found that the natural-lit stores reported 40% higher sales than those without.

For Chris Taffs, marketing director of Solar Spot, the findings aren’t surprising. “Natural light makes people feel better and colours look as they should, so it makes sense that customers will be more inclined to spend longer in retail outlets,” he says.

Large lantern-style skylights in the in-store café at Greensmiths in London’s Waterloo reduce the need for electric lighting, and incidentally solar thermal panels on the roof provide most of the store’s hot water needs.

Kept clean and regularly maintained, these attractive windows to the sky create a bright environment for Greensmith’s shoppers to sit and sip their coffees.

However, there are a few rules when it comes to skylights, the first being that if you are thinking of retrofitting them into your roof, some strengthening might be needed. You should also consider that glare from the overhead sun could cause your air-conditioning to work harder in the summer, and your heating in the winter.

Where you position your skylights is also important. When installed on a north-facing roof, a skylight will provide fairly constant, but cool illumination, which many argue is not that welcoming. One on an east-facing roof would provide maximum light and solar heat gain in the morning, while a west-facing skylight will provide afternoon sunlight, but also unwanted heat in the late afternoon. Because of all these variables, an increasingly popular alternative to skylights are tubular daylighting systems.

Also known as sun or light tunnels, these reflective tubes funnel in daylight from the outside, illuminating your shop floor, back office or stock-room. They can be easily retrofitted into existing roofs, and can fit all manner of roof sizes, shapes and angles.

Depending on the width and efficiency, light tunnels can pipe light over distances that exceed 25 metres, and because of their high reflectiveness require a much smaller opening than a traditional skylight to light even larger spaces, a fact which will also appeal to security-conscious retailers, Taffs adds. To give you an idea of cost, one 375mm diameter unit can light about 20sq m and costs on average £800 to be supplied and fitted.

Like solar panels, light tunnels also do not require clear sunny days to work, but are at their most effective on bright days.

When properly installed, light tunnels can be really effective, minimising the requirement for other forms of electrical lighting. Just ask Ian Proudfoot, joint managing director of the Proudfoot Group, which boasts 30 of them at its 4,000sq ft Seamer store in North Yorkshire.

The tunnels, which were retrofitted into the roof of the 60-year-old store, hardly require any maintenance at all, Ian says. “They give out an excellent natural light and enable us to turn off at least 33% of the store’s internal lighting during the day,” Ian says. “They create a really welcoming atmosphere and help to keep energy bills low,” he adds.

Clear benefits

There are, of course, lots of simple ways to make the most of natural light in your store, without having to splash much cash. A basic cleaning routine can make a world of difference. Energy provider Npower’s White Paper on small business energy consumption recently revealed that without regular maintenance of windows, skylights and artificial lights, light levels in stores can fall by as much as 50% in just three years.

De-cluttering your doors and windows can be equally effective. “Making the most of natural light is one of the simplest ways of keeping costs down,” points out Jonathan. “I never understand retailers who have large windows and clog them up with vinyls, posters and stickers. Letting in natural light reduces the need for you to have as many store lights on, and shoppers prefer it as it means they can see inside, which can be less intimidating.”

So what are you waiting for? Let more light into your life this summer.•