Okay, this is cool: a Seattle-based startup is working to develop a tiny hydroelectric generator suitable for powering low-wattage devices like phones or small LED lights. The "Hydrobee" is a self-contained hydroelectric plant the size of a soda can: when flowing water spins its small blades, the generator feeds a trickle of electrical power into a six-pack of AA nickel metal hydride batteries, charging them up.
The user could then tap that stored power by means of a USB 2.0 connection. It wouldn't be enough power to run your industrial society on, but it might be just right for powering a headlamp or a small flashlight -- and for the two billion or so people in the world without access to grid power, points out Hydrobee founder Burt Hamner, that small flashlight could displace smoky, unhealthy, dangerous, and expensive kerosene lanterns.
The company's Kickstarter mentions that the Hydrobee can be used either by placing it in a stream or towing it behind a boat, or by running a flow through the device from a faucet. That last idea may seem inefficient to water-conserving Californians, but there's nothing saying you couldn't attach the thing to a waterline long-term, charging the batteries as you do the dishes or run your washing machine.
Hamner says that any stream flowing at "walking speed" -- three or four mph -- will turn the turbine, and says a good flow will charge the unit's batteries in four hours. A fully charged battery pack should be enough to provide about ten full charges for a typical smartphone.
Like many small-scale renewable energy innovations the Hydrobee has a split potential market: those off-grid people for whom the product might make a significant improvement in their standard of living, and those whose standards of living are already pretty good, but who like to spend time outdoors.
Having a reliable, long-term source of energy from the nearby creek to power your low-wattage camp light sounds like a pretty good idea either way. A hat tip to Cleantechnica for bringing this to ReWire's attention.