Published on February 16th, 2011 | by Susan Kraemer2
Keeping Clean Energy Clean
So many green jobs are being created by switching energy sources from fossil based to clean energy, but here’s one you might not have thought of. Keeping clean energy clean.The Germans, who are years ahead of us in solar adoption, have already cornered that market!
The German company Schletter GmbH has developed a novel cleaning system for PV module rooftop installations. By positioning himself at the ridge line and letting gravity assist him, a solar maintenance worker can suspend this double rotating brush device down the array to clean it. The whole thing weighs only 15 kg, including the water feed.
Their PVSpin is designed to be operated safely by one person and it uses twin rotating brush heads fed with water through a central nozzle. It can also work on the typical flat roof commercial building, because the two cleaning brushes – rotating in opposite directions – are only driven by water pressure.
Hard dirt formation is removed by the rotation of the brushes and the filtered water. The guidance along the module frames makes cleaning operations more convenient.
The idea is that to operate at optimum efficiency, a solar array needs to be free of dust and dirt buildup. But it is not necessary to be too obsessive about this, actually. Normally a rain shower every few months will take care of it.
Even in dusty California, for example, my own solar array (on a PPA from SunRun) has been working fine for five months now with no cleaning, as I can see from its output online – and my now tiny $4 electric bills! Of course, we have had a rainy winter, so it is cleaner than I would expect in usual California winters.
It is not a huge problem. The way you’ll know that your solar needs cleaning is if you can see dust and dirt build up on the outside of your windows – that can really take a while. But if you want only the best care and maintenance, the German company will have these on the market in April.