Sassy alcohol-powered robots and cola-powered cyborgs are strictly fiction, but two design concepts look at how gadgets using these alternative fuels could become reality.

Product designer Daizi Zheng recently released details on a eco-friendly phone concept designed for Nokia that uses a "bio-battery" instead of a traditional battery. It generates electricity using the carbohydrates (sugar) in a can of cola.

The designers claim that one 12-ounce can of fizzy drink, with roughly 40 grams of sugar, would power the phone for three to four times longer than a single charge from conventional lithium batteries would.

The concept, while not incredibly appealing aesthetically, does offer an alternative to traditional waste-producing batteries. When this battery dies, the residue consists of oxygen and water; far more environmentally-friendly than lithium batteries.

Meanwhile, a few months ago the blog Yanko Design posted a personal mobile device concept designed by Tryi Yeh. Cheers, as it is called, would use a green alcohol-cell battery that provides a more efficient way of saving a battery's energy.

How this technology would work is less clear, but the pictures sure look impressive. And it looks like a flask--flasks are always hip. There are no details on whether or not the alcohol-cell can be drained for an emergency nightcap, though.

Green or gimmicky products usually don't have the lowest up-front cost, but green products have become more popular with comsumers in recent years (see also: hybrids).

Since these are both merely product concepts, it will be a while before you can run out to your local electronics store and buy a Pepsi-powered gadget.

Until then, see Chris Brandrick's roundup of green tech products for more practical ways to green up your tech. If you want to learn more about how bio-batteries work, see HowStuffWorks' article on the topic, and learn how to build your own at Instructables.

[via CNET Crave]