It’s a cliché to start a story about auto-based solar with “here comes the sun,” but, well, here comes the sun. Ford is teaming up with SunPower on a pretty cool idea — since electric cars aren’t all that green if they charge off a dirty coal grid, the company is offering its Focus EV customers a chance to install a 2.5-kilowatt rooftop solar array that can produce 3,000 kilowatt hours of electricity annually, about what you’d need to drive 1,000 miles a month.

It’s called “Drive Green for Life,” which is probably better than calling it “Here Comes the Sun.” The idea is great, but the catch is the price: it’s “less than $10,000,” and that’s after the 30 percent federal tax credit and before local sales taxes.

Of course, you can also shop around and find a better solar deal — the availability of lower-cost systems is exploding, and costs are coming down all the time. Ford says an advantage of the SunPower system is that it offers less of a footprint on your roof, and includes a residential monitoring system that lets you track photovoltaic performance through an iPhone or on the Web.

Solar EV charging is starting to catch on. General Electric unveiled a huge 100-kilowatt array at one of its Connecticut offices, with enough power to charge 13 Chevy Volts a day. A company called EnvisionSolar is installing “solar trees” that provide shade as well as EV charging. Fast-growing SolarCity, which recently went national by setting up solar leasing operations on the East Coast as well as California, is now offering EV charging for $1,500 as part of the deal. According to CEO Lyndon Rive, “Electric cars are already among the cleanest-running vehicles on the road — charging them on solar makes them that much better.”

Did I mention that there’s an annual event called the World Solar Challenge in the Australian Outback, and a three-wheeled ultra-lightweight solar-powered EV made by a Dutch college is now in training for the October event — and claiming to be the world’s fastest solar-powered car? The sun can’t power regular cars — the panels on cars like the Fisker Karma and the Toyota Prius are there to provide some ventilation when the car is parked.

The Focus has been a long time coming, and will be a welcome addition to the stable of major manufacturer electric vehicles. But in 2011, only customers in New York and California will be able to buy a Focus Electric. That announcement created some confusion among those of us who thought it was rolling out to 19 markets, but Ford insisted the car isn’t being delayed — just strategically allocated. California is EV ground zero.

The other markets will have the car in the spring. Here’s the full launch list — is your city on it? Atlanta; Austin, Texas; Boston; Chicago; Denver; Detroit; Houston; Los Angeles; New York; Orlando, Fla.; Phoenix; Portland, Ore.; Raleigh/Durham, N.C.; Richmond, Va.; San Diego; San Francisco; Seattle; Tucson, Ariz.; and Washington, D.C.

Ford CEO Alan Mulally was on David Letterman's show last week with the Focus Electric, so let’s go to the videotape:

Notice that (between the jokes) he said that the car has regenerative braking, and 80 miles of range. That’s not great, but it may allow Ford to position the car somewhat below the Nissan Leaf in price. A $30,000 Focus, with or without solar, would be nice, especially since the Leaf went up to $35,000 for 2012. I’ll take the one that David Letterman drove.

Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

New Ford Focus to come with solar panels (for your home)
Buy the Focus Electric, and a 2.5-kilowatt rooftop solar panel can be part of the deal. This car charges on zero-emission solar power, which is much cleaner tha