Hydropower: Challenged

ambience: Stream, turbine and waterwheel

For thousands of years, people have known how to put water to work. The ancient Romans used water wheels to grind their corn. And it was hydropower that helped make the industrial revolution possible. But some say that now, we need a new way to harness the power of water. I’m Jim Metzner, and this is the Pulse of the Planet.

Large hydroelectric dams are an important source of energy. But engineer Daniel Schneider says there’s an essential problem with the current technology.

“Conventional hydropower uses a rotating device to respond to the movement of water, and the pressure of water, as it flows past that moving blade. That force from the water causes the blade to turn, turns a shaft that in turn drives a generator. Now, the way to get to larger power with that turbine is to make a bigger turbine in diameter. The larger the diameter, the more water can come through it, the more power we get out of it. So, what do we do in conventional hydropower? We increase the height of the dam, so that we can now squeeze more water through a small area. And that becomes a problem for living things.”

Some of those living things are people who have been driven from their homelands to make way for large dams.

“Take the country of Ghana for example. In order to produce inexpensive aluminum for cans, six percent of Ghana is underwater, and it’s all the most valuable land that’s under water. So the people are then forced to move up into the highlands which are infertile.”

Scientists are developing a new way to produce hydropower – and they’re taking their cue from beavers. We’ll hear more about that in future programs.

Pulse of the Planet is presented by the National Science Foundation. I’m Jim Metzner.

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Hydropower: Challenged

With both humans and fish being adversely effected by conventional dams, a scientist has taken a fresh look at hydropower design.
Air Date:07/14/2005
Scientist:
Transcript:


ambience: Stream, turbine and waterwheel

For thousands of years, people have known how to put water to work. The ancient Romans used water wheels to grind their corn. And it was hydropower that helped make the industrial revolution possible. But some say that now, we need a new way to harness the power of water. I'm Jim Metzner, and this is the Pulse of the Planet.

Large hydroelectric dams are an important source of energy. But engineer Daniel Schneider says there's an essential problem with the current technology.

"Conventional hydropower uses a rotating device to respond to the movement of water, and the pressure of water, as it flows past that moving blade. That force from the water causes the blade to turn, turns a shaft that in turn drives a generator. Now, the way to get to larger power with that turbine is to make a bigger turbine in diameter. The larger the diameter, the more water can come through it, the more power we get out of it. So, what do we do in conventional hydropower? We increase the height of the dam, so that we can now squeeze more water through a small area. And that becomes a problem for living things."

Some of those living things are people who have been driven from their homelands to make way for large dams.

"Take the country of Ghana for example. In order to produce inexpensive aluminum for cans, six percent of Ghana is underwater, and it's all the most valuable land that's under water. So the people are then forced to move up into the highlands which are infertile."

Scientists are developing a new way to produce hydropower - and they're taking their cue from beavers. We'll hear more about that in future programs.

Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.

music