Luke Sanders, Author at The Solar Centre Blog

The all-seeing Eye!

Solar and security lights may seem like an unlikely partnership to the uninitiated, but they are actually a perfect match. Some solar sceptics reading this will no doubt chuckle at the idea of relying on solar for their security needs, but hear me out if you will.

Having been in the business for 8 years there is no doubt in my mind that motion activated Solar Security Lights outperform every other type of solar light. They do that by reliably serving the right purpose at precisely the right time of year (even though that right time of year happens to be the wrong time of year from a solar point of view).

As soon as the clocks go back in October and the nights draw in we start to think about security lighting. For manufacturers and retailers of solar lights, the clocks going back is like the grim reaper ushering in the end of days. For a start its one hour less of daylight (where solar lights would normally be charging) and one hour more of pre-bedtime darkness where customers expect their lights to work. It also heralds the beginning of real winter where only the best solar lights in the best locations will work as the sun struggles to make it above the garden fence for 3 months. In summer the UK gets an average of 7 peak sun hours a day, but this drops to just 1 peak sun hour in winter. This means that a typical solar light that works for over 8 hours a night in summer, will work for about an hour a night in winter.

The reason solar security lights work well in winter even though they are brighter than all other solar lights is simple – they are only meant to come on a few times a night as and when they detect motion. This means that they can continue to work reliably through extended periods of bad winter weather and recoup those losses when the winter sun makes an appearance.

Lets crunch some numbers with our latest offering the Eye Solar Security Light (above). The Eye can comfortably deliver 100 minutes of light once fully charged. The average customer will opt for 30 second activations each time the Eye detects motion giving them 200 hundred activations in a fully charged battery. Based on our own experiences, and those of our customers, a busy security light should not be activating for more than 20 times a night. Assuming your light activates 20 times a night you will have 10 nights worth of activations in the battery before any fresh charge is taken into account. A well located solar panel will give the Eye 10 minutes worth of light (20 activations) after a bad winter days charge, around 20 minutes (40 activations) after an average winter day and 30 minutes of light on a good winter days charge (60 activations).

The Eye will not compete with a 500W mains-powered halogen light, but it is more than a match for any 100W fitting which is more than good enough for most household applications. Unlike mains powered lights, solar security lights can be set up anywhere around your property without the need to run cables from your house which can be hideously expensive. You can safely install a solar security light yourself in minutes with minimal DIY skills so there’s no need for an electrician. Best of all is once they are up and running they are completely free to run and will continue to work even if there’s a power cut in your area.

Space technology heads back to earth

The Differences:

Whenever you see footage of a satellite out in space chances are the solar panels you’re looking at are not the same type of panels you see on roofs or in gardens back here on earth. The PV (photovoltaic) solar panels we have been using here one earth since the 1970s convert roughly 15% of the sun’s energy into electricity. The CPV (concentrated photovoltaic) solar panels often used in space are able to convert up to 44% of the sun’s energy into electricity which makes them three times more efficient.

Why The Solar Panels are Different:

CPV panels are more efficient because they use optics to focus large amounts of sun onto wafer thin photovoltaic surfaces to generate more electricity than traditional PV panels. Put simply, imagine setting up a parabolic telescope, pointing it at the sun (not something we recommend) and then sticking a highly efficient multi-junction solar cell in the eyepiece – that’s basically CPV.

Efficiency gain is just the beginning of the good news. A recent report by IMS Research suggests that although the upfront cost of CPV panels will be more expensive, CPV will cost 30% less than PV over the lifetime of a system because CPV produces three times more electricity. CPV panels will also be up to 3 times smaller than equivalent PV panels which will be great news for houses with small areas of south facing roof.

Solar Panels and The Future:

Large CPV solar power stations are already being developed in Europe, Africa, Asia and North America. Residential CPV is still very much embryonic, but there are companies blazing a trail with experimental designs. If all goes to plan you might just see some CPV systems appearing on houses near you by 2025.

Something will have to give…

A recent industry study by Kronos, Germany’s leading solar farm developer, suggests that Britain only has a handful of brownfield sites sufficient for large solar panel farms which puts a fresh dent in the governments pursuit of its renewable energy targets. Salvation is possible, but it does not have a pretty face.

In July an application for a 199 panel farm in Land of Outstanding Natural Beauty in Berkshire was approved. Kronos themselves are currently working on proposals that would see a 250,000 panel farm spanning 100 acres of agricultural land in Hampshire which would generate enough power for 30,000 homes. Conservationists are concerned that the Kronos report signifies a loosening of the cork that is currently preventing the solar farm genie from leaving its bottle and blighting the green fields of Britain. Resistance to renewables is not new of course, opposition to windfarms has been well documented in recent years and there are currently around 300 windfarm action groups in the UK.

Nuclear is seen by some as the only catch-all solution, but doubt has been cast on the commercial viability of the latest EPR reactors that will be the cornerstone of Britain’s privatised modernisation programme. There is also considerable uncertainty regarding regulation of the nuclear industry and nuclear waste disposal. Resistance is strong here too. Both the Welsh Assembly and Scottish Parliament are opposed to new nuclear power stations.

Hydraulic fracturing, or Fracking, has recently made headlines despite being commonplace in the North Sea since the 1970s. Now the drills are making their way inshore serious concerns have arisen regarding earthquake risk and water contamination.

Against this backdrop of opposition there is the looming prospect of a power deficit in the UK where demand is stronger than ever. In June 2013 OFGEM issued a warning stating that the risk of power blackouts in the UK within the next 18 months has doubled since a year ago. In that year Britain’s population, which is now the fastest growing in Europe, increased by 420,000 which is two and a half times the increase experienced by Germany. In 1970 the energy consumed in British homes represented a quarter of Britain’s total consumption; it is now a third thanks to the increase in housing stock which is still regarded as woefully inadequate.

It is almost impossible to find a form of mass power generation, renewable or otherwise, that does not come loaded with controversy and opposition. The time at which an unstoppable force (Britain’s power needs) meets an immovable object (the resistance to virtually all forms of mass power generation) is fast approaching and something will have to give.

Solar will have her revenge…

Nothing is more frustrating to honest solar retailers than the relentless flow of cheap solar lights available on petrol station forecourts and other retail outlets. We often take calls from customers who are keen to try something new, like a solar security light for example, but are having trouble recovering from their last solar light purchase which barley manages a whimper come dusk.

Some point the finger at China but this is often unfair as China simply manufactures to our demand. You can get great products from China and you can also get rubbish much like anywhere else. More worryingly, others point the finger at solar itself as their ‘throw-away’ solar garden light flickers out its final flutter. This can do damage to the solar industry as a whole and also the wider environmental cause. Would you consider solar panels for your house if your only previous experience of solar was a garden light not fit for purpose?

The truth is that both solar and the Far East are capable of generating fantastic products and these products are readily available in our shop as well as many others and they needn’t cost the earth. It is our hope that as time moves on the questions will be about the difference between good solar products and bad solar products rather than the integrity of solar itself.