A team of scientists at MIT have discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes. The discovery could lead to a new way of producing electricity, the researchers say.

The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” says Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings that appeared in Nature Materials on March 7. The lead author was Wonjoon Choi, a doctoral student in mechanical engineering.

Like a collection of flotsam propelled along the surface by waves traveling across the ocean, it turns out that a thermal wave — a moving pulse of heat — traveling along a microscopic wire can drive electrons along, creating an electrical current.

The key ingredient in the recipe is carbon nanotubes — submicroscopic hollow tubes made of a chicken-wire-like lattice of carbon atoms. These tubes, just a few billionths of a meter (nanometers) in diameter, are part of a family of novel carbon molecules, including buckyballs and graphene sheets, that have been the subject of intensive worldwide research over the last two decades.

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One of the interesting side effects of last year’s stimulus bill was $400 million in funding for ARPA-E, the civilian, energy-focused cousin of DARPA. And in this week’s first ever ARPA-E conference, MIT chemist Dan Nocera showed how well he put that stimulus money to use by highlighting his new photosynthetic process. Using a special catalyst, the process splits water into oxygen and hydrogen fuel efficiently enough to power a home using only sunlight and a bottle of water.

In about four hours, water treated with Nocera’s catalyst can produce 30 kilowatt-hours of energy. Moreover, the process is cheap. So cheap, in fact, that Nocera has no problem envisioning a day when each house generates its own fuel and electricity from photosynthesis.

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Material scientists at the Nano/Bio Interface Center of the University of Pennsylvania have demonstrated the transduction of optical radiation to electrical current in a molecular circuit.

The system, an array of nano-sized molecules of gold, respond to electromagnetic waves by creating surface plasmons that induce and project electrical current across molecules, similar to that of photovoltaic solar cells.

The results may provide a technological approach for higher efficiency energy harvesting with a nano-sized circuit that can power itself, potentially through sunlight. Recently, surface plasmons have been engineered into a variety of light-activated devices such as biosensors.

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The U.S. Feeds One Quarter of its Grain to Cars While Hunger is on the Rise!

The 107 million tons of grain that went to U.S. ethanol distilleries in 2009 was enough to feed 330 million people for one year at average world consumption levels. More than a quarter of the total U.S. grain crop was turned into ethanol to fuel cars last year. With 200 ethanol distilleries in the country set up to transform food into fuel, the amount of grain processed has tripled since 2004.

When the growing demand for corn for ethanol helped to push world grain prices to record highs between late 2006 and 2008, people in low-income grain-importing countries were hit the hardest. The unprecedented spike in food prices drove up the number of hungry people in the world to over 1 billion for the first time in 2009.

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Solar technology is going where it has never gone before: onto the shelves at retail stores where do-it-yourselfers can now plunk a panel into a shopping cart and bring it home to install.

Lowe’s has begun stocking solar panels at its California stores and plans to roll them out across the country next year.

This shows how far the highest of the high-tech alternative energy technologies has come. Solar power is now accessible to anyone with a ladder, a power drill, and the gumption to climb up on a roof and install the panels themselves.

For Lowe’s, it’s an opening into a new and potentially lucrative DIY business.

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