EmTech Conference Focuses on Biofuels, Metamaterials

MIT Technology Review's Emerging Technologies Conference last week focused on biofuels' sustainability and production and the use of seed-based biofuels, as well as metamaterials.

Biofuels: Reality Check

Biofuel was a big topic for the EmTech community. Panelists included David Berry, principal of Flagship Ventures, Lee Lynd, professor at Dartmouth College and cofounder of Mascoma, Michael Raab, founder and president of Agrivida and Gregory Stephanopoulos, professor of chemical engineering at MIT.

Topics focused on the sustainability of biofuels and the landmass, progress and resources needed to produce them, as well as the use of seed-based biofuels versus cellulous-based biofuels. Seed-based fuels would include corn and soy, which are specific elements within a plant, where cellulousic biomas includes the stocks and all other elements of the plants.

According to Professor Lynd, there isn’t enough land available in the U.S. to produce enough seed-based biofuel to provide for the entire country's transportation energy requirement. However, he argued, not only could they be met from cellulosic biofuels, “but could be met from cellulosic biofuels within current agricultural lands without decreasing food production.”

David Berry’s company LS9 produces renewable petroleum, which performs the same as fossil petroleum. According to Berry, LS9 is “a company that has basically engineered microbes to take glucose or any form of glucose, i.e. cellulose, etc., and make basically a hydrocarbon of your choice out of that so you could make something that you would put right into your gas tank.”

Metamaterials: Invisible Revolution

Metamaterials are materials reconstructed at the nano level to alter their refractive index and broaden their electromagnetic parameters. A panel on metamaterials at Emerging Technologies consisted of David Smith, associate professor of electrical and computer engineering at Duke University, Marin Soljacic, assistant professor of physics at MIT and Nader Engheta, professor of electrical and systems engineering at the University of Pennsylvania.

“Metamaterials are artificially created materials whose structures vary substantially faster than a wavelength of light,” said Soljacic. This means that by changing the structure of a material, i.e. by inserting gaps at a level smaller than the wavelength of light, it distorts the way the light wave behaves. This is useful for the implementation of photonics into microprocessors because, according to Soljcic, “dynamics for propagation of light are dramatically modified from what it would be in a uniform material.” The dynamics for propagation of light is the widening of a light beam over distance.

Smith’s work is primarily based in cloaking. “We were able to realize this structure, which functions basically as an invisibility cloak in the sense that if you’re looking from one side, it appears as if there is nothing there; both the cloak and the material that it hides are invisible, so it had no reflection and no shadow,” said Smith. 

Smith’s work was tested with microwaves. “From the conceptual point of view, if you can make the materials, you can potentially do the same thing at any wavelength,” says Smith. “The only issue is that you won’t be able to get a very large bandwidth; for example, if you were to do it at optical wavelengths you may not be able to cloak the entire red-green-blue spectrum. You might be able to just cloak one color.”