A large-scale tidal-power unit has started up in Northern Ireland.

The world’s first commercial tidal-power system has been connected to the National Grid in Northern Ireland. Built by the British tidal-energy company Marine Current Technologies (MCT), the 1.2-megawatt system consists of two submerged turbines that are harvesting energy from Strangford Lough’s tidal currents. The company expects that once the system, called SeaGen, is fully operational, it will be able to provide electricity to approximately one thousand homes.

The system is currently being tested and has briefly generated 150 kilowatts of power into the grid. But it has also damaged one of its rotors due to a failure in the control system when the rotor began turning too fast. Although the problem was a minor setback, the unit is not expected to start running continuously and at full capacity until November, says Peter Fraenkel, the technical director at MCT. [ read more ]

Materials that change temperature in response to electric fields could keep computers–and kitchen fridges–cool.

Thin films of a new polymer developed at Penn State change temperature in response to changing electric fields. The Penn State researchers, who reported the new material in Science last week, say that it could lead to new technologies for cooling computer chips and to environmentally friendly refrigerators.

Changing the electric field rearranges the polymer’s atoms, changing its temperature; this is called the electrocaloric effect. In a cooling device, a voltage would be applied to the material, which would then be brought in contact with whatever it’s intended to cool. The material would heat up, passing its energy to a heat sink or releasing it into the atmosphere. Reducing the electric field would bring the polymer back to a low temperature so that it could be reused. [ read more ]

Frances Arnold is designing better enzymes for making biofuels from cellulose.

In December, President Bush signed the Energy Independence and Security Act of 2007, which calls for U.S. production of renewable fuels to reach 36 billion gallons a year–nearly five times current levels–by 2022. Of that total, cellulosic biofuels derived from sources such as agricultural waste, wood chips, and prairie grasses are supposed to account for 16 billion gallons. If the mandates are met, gasoline consumption should decline significantly, reducing both greenhouse-gas emissions and imports of foreign oil. [ read more ]

Physicist Marin Soljacic is working toward a world of wireless electricity.

In the late 19th century, the realization that electricity could be coaxed to light up a bulb prompted a mad dash to determine the best way to distribute it. At the head of the pack was inventor Nikola Tesla, who had a grand scheme to beam elec­tricity around the world. Having difficulty imagining a vast infrastructure of wires extending into every city, building, and room, Tesla figured that wireless was the way to go. He drew up plans for a tower, about 57 meters tall, that he claimed would transmit power to points kilometers away, and even started to build one on Long Island. Though his team did some tests, funding ran out before the tower was completed. The promise of airborne power faded rapidly as the industrial world proved willing to wire up. [ read more ]

A jet engine developed by Pratt & Whitney could revolutionize the aviation industry.

One of the biggest names in aviation has developed a jet engine that is more efficient, less polluting and cheaper to use than almost everything else in the sky, and it could revolutionize an industry facing skyrocketing fuel prices and mounting pressure to clean up its act.

Pratt & Whitney has spent the better part of two decades developing the geared turbofan engine that burns 12 to 15 percent less fuel than other jet engines and cuts carbon dioxide emissions by 1,500 tons per plane per year. It’s being called one of the most exciting developments commercial aviation has seen in years, and it was a hot topic at the Eco-Aviation Conference, where the aviation industry spent two days charting the course to a greener future. [ read more ]

Michael Glantz, the social scientist whose program was recently cut by the National Center for Atmospheric Research, is in Libya at the moment working with the meteorological service there on education programs for North Africa. Before he left, he sent me an open letter calling on the center and its main source of money, the National Science Foundation, to “tear down” the wall between physical science and the social sciences that could help insure that knowledge is applied productively outside the walls of supercomputer centers. The letter is posted below. [ read more ]

Plug-in hybrids are a great way to ease our oil addiction and do something about global warming. But it’s taken 10 years for conventional hybrids like the iconic Toyota Prius to eke out almost 3 percent of the domestic market, and nothing suggests cars with cords will take hold any faster.

For that reason, plug-in advocates say, we’ve got to figure out how to start converting a sizable chunk of the nation’s 240 million cars into gas-electric hybrids you can plug into a wall socket. There’s a handful of companies venturing down this path, but they charge as much as 12 grand to do the job and the number of cars they’ve converted would fit inside a Toyota cargo ship with room to spare. [ read more ]

The legendary venture firm is going green - and leaving Internet deals to the competition.

In the past decade Kleiner Perkins Caufield & Byers has doled out $10 billion to its major investors, all of which are university endowments, philanthropic foundations, or public pension funds. Silicon Valley’s top venture capital firms never divulge their actual performance. Yet this tidbit comes directly from John Doerr, Kleiner’s preeminent partner, who is so intent on ensuring that I’m correctly processing the significance of that figure that he helps me with the math. “That’s $1 billion a year on average,” he says. “Those are great gains. That’s not a couple university chairs, and it’s not a building or two. That’s whole quadrants of a campus.” [ read more ]

Weighing our own prosperity against the chances that climate change will diminish the well-being of our grandchildren calls on economists to make hard ethical judgments

What should we do about climate change? The question is an ethical one. Science, including the science of economics, can help discover the causes and effects of climate change. It can also help work out what we can do about climate change. But what we should do is an ethical question.

Not all “should” questions are ethical. “How should you hold a golf club?” is not, for instance. The climate question is ethical, however, because any thoughtful answer must weigh conflicting interests among different people. If the world is to do something about climate change, some people—chiefly the better-off among the current generation—will have to reduce their emissions of greenhouse gases to save future generations from the possibility of a bleak existence in a hotter world. When interests conflict, “should” questions are always ethical. [ read more ]

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