Saving Solar for a Rainy Day

Solar-powered devices come with a slew of technological hurdles – the power conversion efficiencies of solar panels have improved only incrementally, while the materials for even the most efficient devices remain costly – but engineers and scientists continue to work diligently toward harnessing one of the earth’s most abundant renewable energy resources.

One problem, however, still casts a shadow on the dawn of a new energy era, one that not even the most sophisticated technologies of the future can change (well, the near future anyway): it’s not always sunny.

But it is possible to provide solar power in the absence of sunlight, as two companies demonstrated last month when they announced separately two kinds of solar-powered chargers.

Toyota's solar powered charging station. Image: TechOn

Solar Power on the Go

Toyota Industries Corporation is developing a solar charging station for electric vehicles. Solar cells will generate 100/200V of electricity, which will be stored in spare batteries until it is needed to recharge a vehicle. Since most commuters are gone during the day (read: peak sunshine hours), storing solar energy this way makes it easier to charge electric or hybrid cars during the evening hours, when they are most likely to be parked in a garage. Toyota plans to release a model in late 2010 or early 2011 in Japan for several hundred thousand yen (a few thousand USD).

Solar Cells (The Other Kind)

SunCore, a small, Irvine California-based startup is preparing to release a solar-powered cell phone charger that attaches directly to your mobile device. Almost every cell phone on the market can be retrofitted with SunCore’s embedded light-powered battery. It will more or less continuously charge a phone, provided that users place their phones face-down to expose the battery to light.

SunCore's solar-powered cell phone charger.

Note that I said light, not the sun. That’s because the battery gets its power from the entire light spectrum, from infrared to ultraviolet, making it possible to charge using the light in the room while you watch TV.

For mobile devices without a removable battery, like the iPhone, SunCell has an external solar charger, with the same capabilities, that simply connects via a USB port.

Eternally charged cell phones could enable more powerful mobile applications to run for a longer period of time, which could pave the way for do-it-all devices that play music, stream video or surf the web with ease. On another note, it could drastically increase communication in developing countries without reliable power sources.

The company is preparing a test of its external charger in China, with rumors that cell phone companies HTC and Blackberry are testing the batteries.