Toyota plans to develop special solar panels, that will be sold with limited series of upcoming 2009 Prius – the world’s most popular hybrid. If you thought these will run car on green electricity you are mistaken, as they will solely help power the air conditioning. But still the solar panels should help little vehicle to reach much higher miles-per-gallon figure, some experts estimate it might reach around 100.

Toyota will use Kyocera’s solar cells and with this step Toyota will become first major automaker to use solar power for a serial production vehicle.

Toyota, has sold more than a million Prius models over the past decade and is planning to sell a million hybrids a year sometime after 2010. The car maker plans to produce some 450,000 Priuses at home in 2009, up 60 percent from 2007. The trouble is that almost no one can get a Prius. Supply of the cars is very, very short because Toyota did not anticipate the demand that high oil prices would cause."

If you do not want to wait for 2009 Prius, and already own an older Prius, you might be interested to check out  company SolarElectricalVehicles which is experimenting with do-it-yourself solar panels on a Prius as well. The solar modules are rated at 200-300 watts, and this power is utilized to charge a supplemental battery. With the solar roof, the Toyota Prius can operate up to 20 miles per day in electric mode thus improving fuel economy by up to 29% (depending on driving habits and conditions). The system costs $2.000-$4.000 and the payback time is said to be 2-3 years.

The higher-capacity batteries will add another 10 miles of gas-free driving, says Greg Johanson, president of Solar Electrical Systems, adding that the company is also looking at ways to add the technology to Toyota Highlanders and electric Teslas.The company is also currently experimenting with increasing its 212-watt module to a 320-watt module.

“All the technology is there,” Johanson said. “It’s just the larger manufacturer taking the next step.” For the first 40 miles of a commute, the cars use batteries rather than gas. Forty miles a day is equal to 50 cents a gallon off the utility grid.

With gas prices expecting to break $4 a gallon in the near future, Johanson said they will be gaining in popularity. To date, the company has manufactured nearly 100 of the kits to individual buyers. “Four dollars is the break-even point for these kits,” Johanson said. “Then it pays for itself in two years. That’s where the economics makes sense for the kits. Do you want to own it or do you want to rent energy for the next three years?”