Back in August, Ford announced that it would enter into a partnership with solar panel firm SunPower to help 2012 Ford Focus Electric owners install photovoltaic solar panels on their houses, which could let them power their cars from solar energy.
Called “Drive Green For Life”, the scheme entitles Ford’s Focus Electric customers to a massive discount on the purchase and installation costs of a 2.5-kilowatt peak photovoltaic solar panel array.
The idea, of course, is that the solar panels generate electricity to charge the car during the day -- or to offset any electricity used at night to charge the car, by feeding power back to the grid where possible.
As is often the case with the Internet, however, we’ve seen a rather amusing twist to this story. Some websites have claimed that the 2012 Ford Focus Electric will come complete with a 2.5-kilowatt solar array mounted on its roof.
It’s the traditional chain of Chinese whispers: One website prints an inaccurate story, then gets cited by another, before the claim is transformed into an even more inaccurate story. The chain may continue until there are very few real facts left.
Take the most recent reiteration of this story. Completely confused about the facts, one site actually says that the solar panels will provide enough energy to propel the car along without needing to plug it in.
“This means being able to drive longer distances without having to stop and recharge your car,” the author claims. “It also conserves energy by relying on solar power to help propel the car along, therefore using less of the power contained within the cars’ battery.”
2012 Ford Focus Electric launch, New York City, January 2011
2012 Ford Focus Electric launch, New York City, January 2011Enlarge Photo
For a start, even with today’s modern solar cell technology, a 2.5-kW system normally takes up from 130 to 200 square feet of space - far more than the roof area of any car on the roads today.
Secondly, even if you could fit it onto a car, such a large solar array would dramatically increase the car’s weight and its aerodynamic drag, leading to much reduced performance and economy.
To emphasize the point, a Ford spokesperson confirmed to us earlier today that the SunPower solar cells are meant for your home, not your car: “Otherwise all our aerodynamic improvements would be useless”.
But perhaps the funniest part of this story for us is the idea that an electric car -- fully laden with heavy solar cells, five passengers and a full trunk -- could actually drive at freeway speeds on just 2.5 kilowatts of power per hour.
For the record, the EPA’s official efficiency consumption for the similarly sized 2012 Nissan Leaf is 35 kilowatt-hours per 100 miles -- or 350 watt-hours per mile.
In other words, that’s equivalent to around 7 miles of travel per hour’s worth of solar energy. We think you’ll agree the math just doesn’t add up.
Of course, the SunPower home-based photovoltaic system will be an ideal way to offset the electricity you need to charge your electric car when you’re at home. And it will provide clean, renewable energy for your home when your car isn’t plugged in.
But if you want a car with solar panels that exclusively power the car without depleting its battery pack, your search will lead you to something a little less practical and a whole lot more expensive than a 2012 Ford Focus hatchback.