‘Pole solar’ comes to Nashua – just look up

You can’t install a coal-fired power plant in your backyard, but you can put a solar panel on your roof.That, in a nutshell, reflects one of the most interesting things about electricity from alternative sources: It can be created in lots of small increments all over the place, instead of only in large, centralized facilities.The idea of homegrown energy production isn’t exactly new; it’s what people do when they heat their homes with wood cut from the Back 40, which, until recently, wasn’t possible with electricity.That is changing, as can be attested by the more than 200 homes in New Hampshire that have received state aid to help them produce part of their power with solar panels or, in a few instances, windmills.Nashua saw an interesting example of this philosophy recently when Public Service of New Hampshire installed four solar panels on south Daniel Webster Highway utility poles. They also put up four similar “pole solar” panels in Berlin.Nashua and Berlin got the panels because they, as well as Plymouth, are part of the “Beacon Communities Project,” a state/local partnership that received $10 million in federal funds to reduce energy use and costs in the communities.Putting the 200-watt panels on poles does two things: It raises them out of the way of shadows (and vandals), and makes it easy to plug them into the existing power grid, reducing installation cost and time.Cheaper by the dozenOne of the big advantages of distributed power is that it sidesteps such costs and slowdowns.PSNH spokesman Martin Murray wrote in an e-mail that each installation took about an hour once the bucket truck was on the scene, “akin to plug and play” – just a bit of splicing, and more electrons were flowing into the power lines.By contrast, a large-scale solar facility like the multiple-megawatt plant that PSNH wants to put atop Manchester’s landfill requires the siting and construction of new power lines and even substations.The panels, with some associated hardware and software, are donated for six months by a New Jersey company called Petra Solar, a start-up with an intriguing business model.Petra Solar has received regulatory approval to put up 200,000 such panels in New Jersey, creating what might be considered a 40-megawatt solar power plant scattered throughout the Garden State.(Forty megawatts is about the output of many of New Hampshire’s wood-burning power plants and hydropower dams, although solar panels produce less overall electricity than same-sized power plants because solar only operates a quarter of the time. A megawatt is 1,000 kilowatts, roughly the amount of electricity used by a Walmart Superstore at full power-sucking mode.)The key to Petra Solar’s panels is that they have an integrated micro-inverter, which turns the DC power of a solar cell into the AC used by our electric grid, and an Internet Protocol-based module that allows two-way communication as an aid to a future smart grid.Solar power’s intermittence, as compared to the easily controllable nature of power plants, poses complications for utilities like PSNH. The more information that can flow back and forth from distributed power sources, the better they can be used.As a practical matter, these eight panels will make zero difference to the state’s energy picture, barely generating the amount of power used by a single home over the course of the average day.Their importance is as a role model and test bed, and perhaps symbolism of a future in which alternative energy is part of boring, ordinary life.David Brooks writes the “Granite Geek” column, appearing Mondays in the Telegraph and online at granitegeek.org. He can be reached at 603-594-5831 ordbrooks@nashuatelegraph.com.