Technology converts carbon dioxide, sunlight into ethanol

By Erin Voegele | September 15, 2009
Cambridge, Mass.-based Joule Biotechnology Inc. has developed a new technology that uses a highly-engineered photosynthetic organism, sunlight and carbon dioxide (CO2) to produce ethanol and other biobased products.

Trademarked as Helioculture technology, the modular, direct-to-fuel process requires no agricultural land or fresh water. Joule Biotechnology's modular SolarConverter system is used to facilitate the process, from sunlight capture to product conversion and separation.

In addition to ethanol, Joule Biotechnology's CEO Bill Sims said the technology may also be used to produce biobased hydrocarbon products, such as diesel, and a wide range of chemicals traditionally derived from petroleum.

Sims said that his company chose to validate its Helioculture technology using ethanol. His decision was influenced by the fact that a variety of other companies are also working to produce ethanol, making it easy to make cost and productivity comparisons.

Once commercialized, the company estimates that its Helioculture technology will be capable of producing more than 20,000 gallons of ethanol per acre annually while consuming approximately 150 tons of CO2 per acre per year.

"What we have are highly engineered photosynthetic organisms existing in a solution of nonfresh water … and some nutrients," Sims said. "They exist inside this novel solarconverter that is capturing the sun's rays … We have sunlight as an input and CO2 as a feedstock. So, we are capturing CO2 and driving photosynthesis inside the converter. The organisms have been modified to directly secrete a variety of solar fuels and solar chemicals."

One key difference between Joule Biotechnology's process and cellulosic technologies is the lack of an intermediary feedstock. "There is no biomass, there is no algae, grass or woodchips — or anything else that has to be harvested or grown and processed," Sims said. In addition, the process effectively sidesteps many of the roadblocks that face other second-generation biofuel technologies, including costly biomass production, multiple processing steps, substantial scale-up risk and high capital costs.

According to Sims, Joule Biotechnology expects to break ground on a pilot facility in 2010. He estimates that the technology could be installed on a commercial scale as early as 2012.

"It is our belief that there is just no other technology that has brought forth a true path to energy independence," Sims said. "And, the important aspect of that includes limited land usage. We don't require agricultural land at all, and we do not require fresh water. What we have is a unique direct-to-fuel process that makes the entire Helioculture system far simpler … and allows us to target creating clean renewable fuel at prices at or below that of fossil fuels. At the same time, we are harnessing the power of the sun and converting CO2 — which is something people see as bad — into something usable. From that perspective, we think this is something that is quite a compelling story and entry into the petrochemical space."