Amonix

As solar panel prices have plummeted over the past year, photovoltaic power plants have become a more attractive option for utilities under pressure to meet renewable energy targets.

Case in point: Late last week utility Southern California Edison announced it had signed contracts for 239.5 megawatts of electricity to be generated by 20 small-scale photovoltaic farms.

“Photovoltaics are definitely more cost competitive than they were just a couple of years ago,” said Mike Marelli, director of contracts for renewable and alternative power at Southern California Edison. “We’re seeing just a wild response to our solicitations for projects.”

The utility has inked deals in past years for huge solar thermal power plants that can generate 500 megawatts or more. But those projects — which focus large arrays of mirrors on liquid-filled boilers to generate steam that drives electricity-generating turbines –  need vast stretches of desert land.  Transmission lines must often be built or upgraded to carry the power to coastal cities.

The photovoltaic farms, ranging in size from five megawatts to 20 megawatts, are designed to be built near existing transmission lines or substations and plugged into the grid. And in California, for instance, photovoltaic power plants do not undergo the extensive environmental review required of big solar thermal projects, meaning they can be built much more quickly.