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Reporting and commentary from OnEarth editors and correspondents
This article explains a common misunderstanding about solar energy; namely, that grid-tied PV systems provide power during grid power loss. There is an anti-islanding feature of grid-tied inverters causing them to power down in a blackout. So thanks for reminding people of this, especially in light of Hurricane Sandy's devastation. Correction though: the inverter 'inverts from DC to AC (not the other way).
Good article, except I have to point out that you left out of the discussion one option that really speaks to this issue, the battery-based stand alone system. My wife and I have had one since 2006. It is less expensive and less complicated than a grid-tie battery back-up system. I don’t find battery maintenence to be any big deal. Since deep-cycle flloded lead batteries are better performing, longer lasting and cost less than “maintenance-free” types, it is well worth the trouble to check the water levels every couple months. We have opted to also keep our house wired to the grid. So our solar power has its own set of wires and outlets. Kind of a stand-alone/grid parallel system. Why? Well, we live in town anyway, and the grid makes a great “back-up” to our solar power. A couple months ago, a storm knocked power out for the night in our neighborhood. My neighbor's house across the street with its expensive grid-tie sytem was just as dark as every other house, while we had the only power on our block. For any who might wonder, our 1/2kw system with (x4) 248ah batteries cost about $6K (learning curve included), minus a $2K federal tax credit available at the time. And, oh yeah, cutting waste and using energy efficient technology is a big part of why we only need a 1/2kw system. Questions? (not a business)