IEEE Spectrum: The Biggest Little PV Plant in the East

Description

The northeastern United States is not where most would think to put a photovoltaic power plant. But one just started up in Pennsylvania this winter. It's delivering the watts, but at what cost?

Those involved in conceiving and designing the plant, notably Conergy’s Gary Sheehan and electrical engineering professor Peter Jansson, take obvious pride in their handiwork. They angled the rows of PV modules at 30 degrees with a southern orientation to optimize February and March photon capture, taking into account the need to withstand harsh winter weather and shed snow. (If the only objective were to maximize peak generation and collection of renewable credits, they’d be oriented more toward the west, explains Jansson, who teaches at nearby Rowan University, in New Jersey.) The modules are grouped in strings of 11 to build voltage, and the strings make up rows that can be disconnected independently, for maintenance.

So far, everything is humming along nicely, without actually making any noise at all or in any other way adversely affecting the surroundings. If the plant were built today instead of last year, boasts Jansson, it could be done at a cost of $5 per installed watt, which would be competitive with nuclear construction. Jansson, who was educated at MIT and the University of Cambridge, in England, points out that such PV plants can be built 10 times as fast as a nuclear plant without any of the concerns about local environmental effects, long-term waste storage, and weapons proliferation. “From conceptualization to start-up, it took only about a year to build the PV plant,” says Jansson, whereas for a nuclear plant it would take more like a decade.

That’s a compelling point, but from a narrow economic point of view, it’s also a little misleading. A nuclear power plant, once built, can be expected to run full tilt for at least 40 years, producing electricity 90 percent of the time. A PV plant, in contrast, has a less-well-demonstrated life span and will generate electricity only about a third of the time. To compete economically with nuclear, it needs to be significantly cheaper to build.

Original URL

http://www.spectrum.ieee.org/apr09/8447

http://www.spectrum.ieee.org/apr09/8447