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The Best—And Craziest—Ideas at the ARPA-E Future Energy Pitching Session

Early-stage energy startups faced down a panel of investors; could these ideas really work?

3 min read
The Best—And Craziest—Ideas at the ARPA-E Future Energy Pitching Session

Last night at the Advanced Research Projects Agency—Energy (ARPA-E) Innovation Summit in Washington, D.C., eight early-stage energy startups had three minutes to sell a panel of high-level angel investors and venture capitalists on their hair-brained schemes. The ideas on the table ranged from innovative geometries for vehicle natural gas tanks to wireless electric vehicle charging schemes; here are three that stood out to me.

Altenera Technology: Rotation-free, noiseless wind power

The Altenera BreezeBee is a wind turbine that doesn't turn. Okay, so it's not really a turbine. It is instead a grouping of vibratory "reeds." The hexagonal panels incorporating these reeds can snap together "like LEGOs," making the idea scalable to virtually any size. Chase McCarthy, who presented the idea to the panel, says the first goal is to combine the BreezeBee with solar installations or to throw them up on water towers and similar structures; he estimated a cost of between 10 and 20 cents per kilowatt-hour, making it competitive with other wind technologies.

How, exactly, the BreezeBee works isn't entirely clear. McCarthy says the reeds vibrate and make use of Faraday fields, but that was about it. He says it is patented, though. Still, the claim of "noiseless" was questioned by some on the investor panel, considering the fact that vibrations are involved. McCarthy was also a bit short on some wind power-relevant details such as price per kilogram of material, and energy generated per unit area. The investors were a bit ruthless: without some of that info, one said, "It's a hobby." Still, a vibrating wind power device that requires basically no moving parts in the way a standard turbine does has undeniable appeal.

Gravaton Energy Resources: Ambient temperature change converted to mechanical energy

There is a chance—a chance!—that this company has solved the world's energy problems. We're a bit short on numbers at the moment, but it certainly sounds good: Gravaton has invented a device that captures the energy in ambient air temperature changes and turns it into storable, usable mechanical energy.

Essentially it works like this: as the temperature outside changes, the pressure inside a cylinder also changes. That pressure change can raise a mass within the cylinder. When it reaches the top, the mass can sit and wait until energy is needed, when gravity brings it back down through the cylinder and turns a turbine to create electricity. Mike Brewer, one of the company's founders, presented the idea and said they have already completed a small prototype proving the concept is feasible. A "continuous cycle" prototype is three months away, and an actual 100-kilowatt power plant version of this could be built within 18 months, given the right funding. The numbers he did offer sound a bit too good to be true: a levelized cost of electricity of around 2 cents per kilowatt-hour, and that 100-kw plant would have a footprint of only 20 feet by 30 feet.

The investor panel was a skeptical bunch; it seems there might be a chicken-and-egg problem here: The money folks need to see a bigger prototype in action before funding it, but the company can't build it without the funding. And part of me still feels like this somehow violates some law of physics or other.

Transatomic Power: Uranium molten salt reactor

This idea had by far the most history and star power behind it; molten salt reactors have been under investigation for decades, and Transatomic's pitch was given by CEO Russ Wilcox, who previously founded E Ink, of Kindle electronic paper fame. (He sold that company for almost half a billion dollars, in case you're wondering).

The humbly named Waste-Annihilating Molten Salt Reactor, or WAMSR, uses nuclear waste that is dissolved into a flouride salt form instead of the standard solid uranium used in common fission reactors. The advance that the company claims over previous attempts—thanks to work primarily by two M.I.T. graduate students, Mark Massie and Leslie Dewan—is a design that essentially shrinks the reactor by a factor of 20. Wilcox said this type of reactor can use up to 97 or 98 percent of the nuclear fuel, compared to about 3 percent in a standard solid fuel reactor. The company is nothing if not ambitious; according to the website, "at full deployment, our reactors can use existing stockpiles of nuclear waste to satisfy the world’s electricity needs through 2083." For the moment, they're aiming for a 500-megawatt reactor (about half the size of standard nuclear reactors) that would cost $1.7 billion, far cheaper than nuclear costs tend to run.

Wilcox claimed the different type of plant, with basically no risk of meltdown, would alleviate public fears surrounding nuclear, which is a central blockade to its use. I might argue that the general public won't necessarily grasp the difference—it is still uranium, after all—but there is a definite appeal to a relatively modular, somewhat cheap system that could burn up our nuclear waste and render the Yucca Mountains of the world obsolete.

Image: Altenera Technology

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