If subway stations could harvest the energy of incoming trains as they hit their brakes, they could re-use that same energy to launch the same train as it leaves the station. That's the idea behind Vycon flywheels, which are gigantic spinning wheels that act as temporary energy storage mechanisms. The energy savings of having a flywheel in a station could be tremendous, says the company. In 30 seconds, a decelerating subway train with electric brakes can put up to 4 megawatts of power into a flywheel via the station’s electric third rail -- that's enough to run 1,300 average U.S. …

A research team at Chile's La Silla Observatory has found a new crop of 50 exoplanets, at least one of which is in the "habitable zone" (i.e. an Earthlike distance from the sun). HD 85512 b is rocky instead of gaseous, big but not too big, and preliminary observations suggest an average surface temperature of a balmy 77 degrees F -- all of which make it a good candidate to be Earth Mark II. Phew, just in time! This one's almost worn out! Of course, there are a LOT of unanswered questions -- "does this planet even have water" being …

In its recent report on the company's carbon footprint, Google said that it offsets its emissions with high-quality offsets. We are happy as a pig in shit about that. Which is appropriate, because here's one example of what that means: energy powered by pig poop. The company has invested in a North Carolina project which collects the methane from the waste of 9,000 hogs. A power plant burns the methane to create power for 35 homes a year. This isn't an energy solution that will power the entire country (too many hogs required), but it does keep the methane, a …

In 2010 the world spent $30 billion on solar panels. By 2020 that figure will be $70 billion, says Korean electronics giant Samsung. This despite the fact that the solar market has a bumpy ride ahead of it. Germany and Spain, two of the world's biggest consumers of panels, are phasing out incentives for solar as the market matures and panel prices continue to fall. Another challenge facing the industry is that supply outstrips demand, leading companies to consolidate -- mostly to the benefit of Chinese panel makers and at the expense of U.S. firms (and, right now, Samsung, which …

The scariest horror movies end with a hint that the killer or monster, though defeated, isn't dead and will rise again. With tropical storms sweeping through the Gulf, coastal residents are finding that zombie residues of the BP oil spill are coming out of their lairs to re-terrorize beach-goers, boaters, and the fishing industry. Tides hustled up by tropical storms are bringing oily residues, tar mats, and tar balls onto the beach. It's as bad as it sounds. Check out these pictures that NRDC collected — if you want to brave the sight of oozy, giant, black tar creatures. NRDC …

Boehner's got his hands all sooty with coal money. Uh, guys? Maybe we should check up on the safety of  nuclear plants? Kthx. XOXO, the Nuclear Regulatory Commission. California chose solar PV projects over solar thermal projects because the latter use more water. If Cuba’s new drilling project is possibly going to spill oil into the Gulf of Mexico, just by existing, can't we just get permission to go on vacation there and call it sorta kinda even? The Fish and Wildlife Service is protecting parts of the Florida Everglades' headwaters by buying away development rights from landowners. Stick it …

Shazam! Is it an Autobot, or an object lesson in the possibilities of distributed generation? We're grooving so hard to the soundtrack on this video that we can hardly tell. Unlike conventional ice cream trucks, which sit on the street loudly idling in order to run their refrigeration equipment, this one relies on the power of the sun to keep its wares cool. That means less noise and air pollution. Take that, Mr. Softee!

For those of you who won't have the opportunity to see these homes in person on the National Mall in Washington, D.C., from Sept. 23-Oct. 2, we've decided to gather up all the video walk-throughs of this year's entries in the Department of Energy's Solar Decathlon. All of these homes are extremely energy efficient and, of course, solar-powered. There are more than 20 entries in this year's solar decathlon, and we'll be bringing you walk-throughs of every entry. Massachusetts College of Art and Design plus University of Massachusetts Lowell's 4D home. Rutgers plus New Jersey Institute of Technology's ENJOY House …

A new plan for a massive shift to renewables could move Japan away from nuclear permanently, even as it creates hundreds of thousands of jobs for the country's ailing economy. The plan, which was crafted by Greenpeace, the German Aerospace Center, and the Institute for Sustainable Energy Policies, has the country getting off nuclear completely by 2012. That would involve energy conservation measures equivalent to 10 to 12 nuclear reactors, or about 11,000 megawatts (MW), and a ramp-up of wind power generation from 3,500 MW to 47,200 MW by 2015. Throw in some solar panels -- enough for about 20 …

Last week, sea ice coverage in the Arctic dropped to a new record low, according to data from the University of Bremen. It's the lowest since 1972, when we started observing sea ice via satellite, but it could well be the lowest in 8,000 years. And it's more than 10,000 square feet below the previous record, set in 2007. Yes, this is because of climate change, and yes, it's going to get worse, say researchers: Increased sea ice melt is an unerring indicator of climate change. With ice cover now also thinner than in previous decades, there is “a greater …