This morning, officials will turn on the power at the Keystone Solar Project in southern Lancaster County.
The 5-megawatt project consists of about 20,000 solar panels in ground-mounted arrays on farmland along Lancaster Pike in East Drumore Township. It is the largest solar project in the state, as the Business Journal reported in August, though a project proposed for Franklin County would surpass it.
The arrays will produce about 7.5 million kilowatt-hours of electricity per year, reducing pollution by an amount equivalent to taking 3,000 cars off the road, according to Community Energy, the Radnor-based developer of the project.
Public and foundation money helped the project along. Ben Franklin Technology Partners, the Commonwealth of Pennsylvania and the Sustainable Energy Fund all contributed. Moreover, Exelon Generation is buying most of the power, which will help it comply with Pennsylvania law requiring power companies to have a certain amount of green energy in their portfolios.
Subsidies for renewable have been a politically contentious issue. Skeptics often argue that governments artificially support technologies that could never survive in the marketplace on their own. Advocates retort that fossil fuels receive plenty of subsidies themselves.
The Keystone Solar debut got me to wondering what the consensus is these days on "grid parity" — the crossover point at which solar becomes economically competitive with conventional sources. How close are we?
It turns out there's not much consensus at all. Opinions vary widely, and it's hard not to see ideology driving much of the debate.
For example, AllianceBernstein analysts made waves earlier this month with a blog post asserting grid parity is a will-o'-the-wisp, forever remaining just beyond the horizon of practicality.
Solar advocates swiftly offered rebuttals, pointing out among other things that electricity costs vary by time and place. During peak usage periods, and in places like Hawaii where energy is expensive, grid parity has arrived, they said.
Indisputably, solar costs have dropped dramatically. Many analysts expect that to continue. The costs of solar cells may even become "negligible" in a few years, according to Richard Muller.
The problem is that other capital costs, such as inverters, will continue to keep the economics of solar challenging, he writes in 2012 book, "Energy for Future Presidents," a survey of energy issues written for nonspecialists.
GlobalData, a business research firm with offices around the world, predicts grid parity will take hold across the U.S. from 2014 through 2017. To maintain momentum, solar firms must continue focusing on technological innovations and make "desperately needed" improvements in storage capacity, the company says.
It should be noted that grid parity is a straight dollars-per-energy-unit comparison. It takes no account of the health and environmental benefits of green energy.
If you value those factors highly enough, you could argue grid parity is already a reality.