Energy and Environment Reporting for Texas

How One Man’s Roof Paid for His Car

A Chevy Volt gets a charge in Austin. Photo by Nathan Bernier, KUT News.

It’s the first feel-good sustainability story of 2012. A man in Orlando, Florida installed solar panels on the roof of his home, sold the excess power back to the grid, and then used that money to make a down payment on a new Chevy Volt, the plug-in car that gets 60 miles to the gallon.

Now those solar panels are charging his new car.

Bob Stonerock has made $5,600 from selling excess power from his solar roof panels back to the grid over the last two years, the Orlando Sentinel reports, and used that cash to make a down payment on the Volt. The paper says Stonerock “estimates that he will be able to fuel the car almost exclusively from the electricity from the solar panels that power his vehicle-recharging station.”

But before you start attaching panels to your own roof, keep in mind that Stonerock’s solar success is in part due to some creative accounting.

He tells the Sentinel that he “thinks he has the largest residential solar plant in the Central Florida and one of the largest in the state,” with panels that cover all of his roof and even more in his yard. Those panels didn’t come cheap, and he estimates it will take 50 years for them to pay for themselves. So while he has made money from selling back to the grid, it will take decades for that money to cover the cost of his miniature solar factory.

But the story is some good news for General Motors, which sold only 6,200 Chevy Volts in the U.S. last year, about 2,500 fewer cars than the other plug-in vehicle on the market, the Nissan Leaf. And In November, the National Highway Transportation Safety Board announced that it was launching an investigation into Volt batteries that caught fire several weeks after crash tests. GM offered to buy back the Chevy Volt cars from anyone who wished to return them. As of early December, only a few dozen had taken up GM on the offer.

And on Monday, a Pennsylvania lawmaker (and former Chevy dealer) introduced legislation to end the $7,500 tax credit for the Volt. Rep. Mike Kelly (R-Pa.) wrote in a recent USA Today op-ed that GM sells hundreds of Volts a month, but sells thousands of other vehicles, which demonstrates a “lack of mainstream market demand.” Rep. Kelly says that the average income of a Volt buyer is “$175,000 a year, a large percentage of whom are disproportionately concentrated throughout Southern California.”

To top it all off, GM was the worst-performing auto stock of 2011, according to The Motley Fool, with a 46% drop over the year.


  • I use my Solar in CT to power my Volt with less sun compared to Florida…. featured article is attached:



  • I wish this story or the Orlando Sentinel one was clearer about who paid how much for what, especially before running with headlines suggesting a solar power installation on this man’s roof paid for his car. But given that the owner concludes it will take 50 years before the solar panels pay for themselves, I wonder how it is that the panels have already paid for the car.

    Another problem, of course, is that solar panels are typically expected to have at most a 25-30 year lifespan, making a 50 year payback plan a bit of a problem.

    • Thanks for reading and chiming in, Michael.
      We mentioned that he used some “creative accounting.” According to an article in Orlando Magazine, he spent “about $170,000, more than three times the going rate, on his solar power system.”  
      http://www.orlandomagazine.com/Orlando-Magazine/April-2009/Eco-Crusaders/  As we write above, “Those panels didn’t come cheap, and he estimates it will take 50 years for them to pay for themselves. So while he has made money from selling back to the grid, it will take decades for that money to cover the cost of his miniature solar factory.”

  • Ioioi

    My solar install dropped my electric bill by $330 per month. That savings is being used to pay back the solar loan in five years (my cost was $22K). This encouraged me to buy a Volt. I get 50 miles per 10kW of electricity, the amount used in a single charge. Here, where electricity is extremely costly ($.45 per kW), that translates to $9 to drive $100 miles. Since gas in Hawaii is $4.50 per gallon, the electric cost is equivalent to a gasoline car getting 50 mpg. However, on days that I am home to charge with sunlight, the cost is half, since that is power I would otherwise sell back to the power company for $.25 per kW. My fuel savings using electric rather than gas covers a third to half of the Volt payment. I love it.

    • Abctexas

      How is it that your electricity bill is 350 dollars?  Is that typical in hawaii?

      • Ioioi

        I live on Kauai, where we have a local power company and a single power plant. There is o feasible connection to outside sources We pay the highest electric rate in the country as a consequence. National average is something like $.11 per kW vs. about $.45 here. It’s easy to run up quite an electric tab even without heat or a/c. Nevertheless, an efficient electric car is incredibly cheaper TO THE EXTENT THAT YOU DRIVE NO FARTHER THAN A SINGLE CHARGE each trip between charges. That varies with many factors. Here we have few hills and little need for heat or a/c, so we get 50 miles per charge. Once the gas range-extender generator kicks in to create the electricity, it still gets 41 mpg from the gasoline- generated electricity. Further, it’s a fun car to drive.

About StateImpact

StateImpact seeks to inform and engage local communities with broadcast and online news focused on how state government decisions affect your lives.
Learn More »