The U.S. has a newfound abundance of cheap natural gas which is used extensively for heating and electricity production. Natural gas is arguably greener than petroleum depending on how it is extracted. It inarguably poses less of a national security risk than foreign oil.

Siluria is looking to use natural gas as a low-cost feedstock for a variety of other fuels and chemicals, typically synthesized from petroleum sources.

To that end, Siluria just raised another $30 million in a round C led by new investors Bright Capital and Vulcan Capital along with existing investors ARCH Venture Partners, The Wellcome Trust, Alloy Ventures, Kleiner Perkins Caufield and Byers, Lux Capital, Altitude Life Science Ventures and Presidio Ventures, bringing Siluria's VC total to more than $63 million.

Let's talk about ethylene. Ethylene is the most produced organic compound in the world, according to Chemical and Engineering News, with global production exceeding 107 million tons in 2005. The compound is used to make a wide assortment of plastics and chemicals.

Ethylene is currently created via an energy-intensive process from a petroleum feedstock which, like most U.S. petroleum, comes from a cartel that doesn't have the United States' best interests at heart. Siluria sees its process as providing gas producers and distributors with higher value markets and consumers with lower prices.

Siluria looks to use a low-temperature catalytic-based process called "oxidative coupling of methane" (OCM) with catalysts identified using high-throughput screening tools and produced with biotech. The startup claims that its process is scalable using commercially available equipment. Those claims will look to be proven out at the 10,000-gallon-per-year demonstration facility the firm looks to build with its funding.

The financial and technical gap between demonstration facilities and pilot production is immense for a startup. Siluria will require considerably more funding from its VCs -- or the entrance of a more strategic investor -- if it is to become a chemicals producer. Considerably less funds would be required if the firm supplies the catalyst and licenses the process. The firm will look for joint ventures with the bigger players, according to a Siluria spokesman.

Siluria was spun out of another startup called Cambrios Technologies. Much of the company's technology derives from the work conducted by Angela Belcher at MIT whose team has devised other microbes which can help generate fuel, battery, and semiconductor materials.   

Tags: alloy ventures, angela belcher, bill joy, biofuels, biology, byers, caufield, chemistry, kleiner, kpcb, methane, mit, natural gas, perkins, plastics