Mass. company making diesel with sun, water, CO2

CAMBRIDGE, Mass. – A Massachusetts biotech company is claiming it can produce renewable diesel fuel using the same ingredients that make grass grow.

Joule Unlimited in Cambridge says it has invented a genetically-engineered cyanobacterium that simply secretes the diesel — or ethanol — at remarkable rates.

The organisms live in water and take in sunlight and carbon dioxide. They then produce and directly secrete ethanol or hydrocarbons — the basis of various fuels, such as diesel — as a byproduct of photosynthesis.

Other methods for making fuel from solar energy use "biomass," such as corn or algae. Joule says its technology is far less expensive.

Joule claims its work can change the world, but skeptics say the company may have trouble efficiently collecting the fuel they produce and also must demonstrate their technology on a broad scale.