Alternative Energy Vietnam: Pico Hydro - Small Scale Hydro-Electric Energy
Hanoi, the booming capital of Vietnam, according to the BBC epitomises the country's Asian tiger status. But while the standard of living in the cities has risen dramatically over the last few decades, in the countryside it is a different story.
The mountainous Da Bac province, outside Hanoi, is home to the Muong indigenous ethnic group. Many are rice farmers and few can afford the electricity from the new pylons that line the valleys. Instead, they are turning to a low-priced alternative.
Pico Hydro is a small-scale version of conventional hydro-electric power generation. The streams at the bottom of the valleys are powering a low-tech grid for the people of Da Bac.
Pico Hydro units need only a constant water supply and a slope with a one-metre drop. This produces a flow rate that can drive a turbine fast enough to generate electricity, providing houses with a direct power supply.
In some villages nearly every household has one. Imported 300-watt turbines cost about US$20, and have proved to be the most popular.
"Using Pico Hydro is really easy. There aren't any difficulties. It's actually more difficult to use the high voltage grid - it's much more expensive for us," says Ban Van Giang who lives in Da Bac.
"With better lighting, my wife can work and walk in the house easier, and my children can have better light to do their homework."
Vietnam has the world's highest uptake of Pico Hydro, with 120,000 units installed so far.
Cheap renewable means of generating electricity like Pico Hydro are key to spreading the benefits of electricity throughout the world in a sustainable way.
full BBC News article on water purification and small scale hydro power generation