FASTER, PLEASE: Progress toward solar cells that can compete with coal?

But if you want the off-peak market, you’ll have to price your cells at about US $1 per watt. That price is called grid parity, and it’s the holy grail of the photovoltaic industry. At least 80 firms around the world, from Austin to Osaka, are in the chase.

Surprisingly, at the moment no company is ­closer to that grail than a little start-up called First Solar, which until very ­recently had been known only to specialists. It’s located in Tempe, Ariz., and analysts agree that it will very likely meet typical grid-parity prices in ­developed countries in just two to four years. It’s got a multibillion-dollar order book, it’s selling all the cells it can make, it’s adding production capacity as fast as it can, and its stock price has rocketed from $25 to more than $250 in just 18 months.

I hope that they — and others — succeed in that time frame.