Backpack Hydroelectric Plant

Energy sure is a hot topic, perhaps behind health care and taxes, but still hot.  Wired Science has an interesting article about a human-portable generator, weighing about 30 pounds and capable of generating 500 watts of off grid power.

Backpack Hydroelectric Plant Gives You 500 Watts on the Move

wmspp1A human-portable hydroelectric generator that weighs about 30 pounds and generates 500 watts of power may soon be a new option for off-grid power.

Developed by Bourne Energy of Mailbu, California, the Backpack Power Plant can create clean, quiet power from any stream deeper than 4 feet.

The company showed off its more-rugged, militarized version of the Backpack Power Plant at the Cleantech Forum in San Francisco last week. Bourne Energy CEO Chris Catlin estimates the system will cost $3,000 after it goes into production.

“The BPP-2, which operates silently with no heat or exhaust emissions, is 40 percent less visible during operation and can also be bottom mounted to be totally invisible,” the company maintains.

Off-grid solar cells are also quiet, but they don’t make much power relative to the mini-turbine. For example, one commercially available foldable solar panel measures about 12 square feet and produces 62 watts of peak power. You’d need 60 square feet of panels to get the same peak power as the BPP-2, and the panels would only generate electricity while the sun was shining.

To install the civilian BPP, you would dig two trenches on opposite sides of a river and insert a lightweight anchor into each. Then, you’d run a synthetic rope between the anchors and the BPP. Catlin said his company designed the system to work like the high-tension mooring systems that hold up floating oil rigs.

The military version of the BPP has been designed to work with a variety of flow rates. The civilian version was designed to function best in streams moving at 2.3 meters (7.5 feet) per second.

The civilian market for a $3,000 mini hydro system might not be huge in the industrialized world, but Catlin hopes the plant will find willing customers in developing nations and the military.

“This can bring a cheap, highly portable energy technology to remote areas and remote villages,” Catlin told

Bourne is currently looking for $4 million in venture capital to take the BPP from prototype to production.

Photo courtesy Bourne Energy

See Also:

WiSci 2.0: Alexis Madrigal’s Twitter, Tumblr, and green tech history research site; Wired Science on Twitter and Facebook.

Read More

Sidewalk Power

During our discussion of AC power, we digressed a bit into alternate sources of energy to supply the work required to generate electrical power. One interesting idea is to gather the work-energy in urban areas as people walk along specially designed sidewalks.

Sidewalk Power
Sidewalk Power

A number of other creative ideas can be explored on the site from which the above picture was captured.

Another site with some relevant information:

New Nanogenerator May Charge IPods And Cell Phones With A Wave Of The Hand

ScienceDaily (Mar. 27, 2009) — Imagine if all you had to do to charge your iPod or your BlackBerry was to wave your hand, or stretch your arm, or take a walk? You could say goodbye to batteries and never have to plug those devices into a power source again.

Pictured is a schematic illustration shows the microfiber-nanowire hybrid nanogenerator, which is the basis of using fabrics for generating electricity. (Credit: Professor. Z. L. Wang and Dr. X. D. Wang, Georgia Institute of Technology.)
Pictured is a schematic illustration shows the microfiber-nanowire hybrid nanogenerator, which is the basis of using fabrics for generating electricity. (Credit: Professor. Z. L. Wang and Dr. X. D. Wang, Georgia Institute of Technology.)

In research presented at the American Chemical Society’s 237th National Meeting in Salt Lake City, Utah on March 26, scientists from Georgia describe technology that converts mechanical energy from body movements or even the flow of blood in the body into electric energy that can be used to power a broad range of electronic devices without using batteries.

“This research will have a major impact on defense technology, environmental monitoring, biomedical sciences and even personal electronics,” says lead researcher Zhong Lin Wang, Regents’ Professor, School of Material Science and Engineering at the Georgia Institute of Technology. The new “nanogenerator” could have countless applications, among them a way to run electronic devices used by the military when troops are far in the field.

The researchers describe harvesting energy from the environment by converting low-frequency vibrations, like simple body movements, the beating of the heart or movement of the wind, into electricity, using zinc oxide (ZnO) nanowires that conduct the electricity. The ZnO nanowires are piezoelectric — they generate an electric current when subjected to mechanical stress. The diameter and length of the wire are 1/5,000th and 1/25th the diameter of a human hair.

In generating energy from movement, Wang says his team concluded that it was most effective to develop a method that worked at low frequencies and was based on flexible materials. The ZnO nanowires met these requirements. At the same time, he says a real advantage of this technology is that the nanowires can be grown easily on a wide variety of surfaces, and the nanogenerators will operate in the air or in liquids once properly packaged. Among the surfaces on which the nanowires can be grown are metals, ceramics, polymers, clothing and even tents.

“Quite simply, this technology can be used to generate energy under any circumstances as long as there is movement,” according to Wang.

To date, he says that there have been limited methods created to produce nanopower despite the growing need by the military and defense agencies for nanoscale sensing devices used to detect bioterror agents. The nanogenerator would be particularly critical to troops in the field, where they are far from energy sources and need to use sensors or communication devices. In addition, having a sensor which doesn’t need batteries could be extremely useful to the military and police sampling air for potential bioterrorism attacks in the United States, Wang says.

While biosensors have been miniaturized and can be implanted under the skin, he points out that these devices still require batteries, and the new nanogenerator would offer much more flexibility.

A major advantage of this new technology is that many nanogenerators can produce electricity continuously and simultaneously. On the other hand, the greatest challenge in developing these nanogenerators is to improve the output voltage and power, he says.

Last year Wang’s group presented a study on nanogenerators driven by ultrasound. Today’s research represents a much broader application of nanogenerators as driven by low-frequency body movement.

The study was funded by the Defense Advanced Research Projects Agency, the Department of Energy, the National Institutes of Health and the National Science Foundation.

Adapted from materials provided by American Chemical Society, via EurekAlert!, a service of AAAS.

Turning the Tide to Energy: New Concept Could Harness the Power of Ocean Waves

Ok, perhaps this post is more related to physics 53 material [pressure, fluids and energy] rather than physics 54, but it is highly relevant to the Nicholas School of the Environment and Duke Marine Lab, and it deals with the physics 54 topic of AC-generators.  Besides, it is just cool “sustainable” energy technology.

NASA researchers who developed a new way to power robotic underwater vehicles believe a spin-off technology could help convert ocean energy into electrical energy on a much larger scale. The researchers hope that clean, renewable energy produced from the motion of the ocean and rivers could potentially meet an important part of the world’s demand for electricity. …

read the full story here

Hydrokinetic Energy Transfer System
Hydrokinetic Energy Transfer System