a lolly that says "extinction sucks"Photo: Geek Calendar

Clean technology is full of ideas that may or may not work out, for any number of reasons — modular nuclear, distributed power, humanure. Whether it’s economics, physics or simple incompatibility with existing infrastructure, here, via Michael Kanellos (the David Pogue of clean technology) are 10 ideas that could work, but probably won’t.

1 Stirling engines

What’s wrong with Stirling engines: Stirling engines are external combustion engines that work by expanding and compressing a gas (unlike steam engines, which work by converting liquid water into gas). In theory, Stirling engines (invented in the 1800s) are the most efficient engines in the world, but you don’t have one in your car because they take a while to warm up

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Kanellos says that attempts to make them work as a part of solar power collectors are currently doomed.

*Stirling engines, however, also suffer from a major problem: competing technologies work better. The SunCatcher at its core is powered by a rapidly moving piston: try keeping that operating flawlessly in the desert for 25 years at a stretch. Stirling engines also remain the only solar thermal technology without an inherent mechanism for storing heat. The declining price of solar panels damaged this technology’s potential, as well.

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What might redeem Stirling engines: Inventor Dean Kamen is building a hybrid vehicle that incorporates a Stirling engine.

1 Portable methanol fuel cells as an alternative to batteries

What’s wrong with fuel cells: Traditional lithium-ion batteries have limited capacity to store energy — a major problem as our portable devices become ever more power-hungry. One way to get around this would be to tap the significantly higher energy density of liquid fuels. (It’s no exaggeration to say that the most effective — if not the most green — solution would be a laptop that runs on gasoline.)

Fuel cells work — that’s not the problem:

*Why would a consumer want to carry around a little jug of flammable liquid to charge up their camera or phone when they could just 1) carry some spare batteries or 2) plug it into a charger?

*You never get a straight answer.

What might redeem fuel cells: Even a 10-gallon tank of gas has as much explosive energy as 800 sticks of dynamite, but that hasn’t stopped us from figuring out how to make motor vehicles (relatively) safe. And even if you don’t want to keep a fuel cell in your pocketbook, the technology might make inroads in industrial applications.

1 The three-wheeled car

What’s wrong with ditching the fourth wheel: Ever since Buckminster Fuller’s Dymaxion car, which carried 11 but still got 30 miles to the gallon, it’s been widely recognized that fewer wheels equals less friction and a more aerodynamic profile — both ways to significantly increase fuel effiency.

The problem isn’t that these cars don’t work; it’s that car consumers are notoriously conservative in their choice of vehicles, and a vehicle like an Aptera just doesn’t scream “reliable, affordable, and good in a crash with some jackass’s Avalanche” to most buyers.

What might redeem modern three-wheeled vehicles: Economics has a funny way of overcoming our biases. If oil becomes radically more expensive, vehicles that get up to 300 mpg will become appealing.

1 The rest…

Kanellos butchers a number of other sacred cows, from recycling fryer grease to run our cars to personal wind towers — for the full list, check out his original.