Texas Manure-to-Gas Plant Creates Energy, Cleans Up Waste

Texas is famous for its expansive landscape, oil production and ranching. Cattle ranches and dairy farms are normally associated with steak and milk, but renewed interest in anaerobic digesters, the process of converting manure to energy, is giving ranching a share of the renewable energy market. Just outside of Stephenville, Texas, the largest digester facility in North America is turning cow waste into biogas.

The facility, which covers 73 acres in Erath County, Texas, offered a unique solution for the tons of waste left by dairy cows. Officials from Waco, located downstream from Stephenville, blamed contamination of their water supply on manure from the farms. Microgy’s offer to clean up the manure at no charge and convert it into green energy was met with open arms from both communities.

The plant uses eight anaerobic computer-controlled digesters to transform the manure into biogas. Water is mixed with the manure and run through the five-story, 916,000-gallon digesters. This process creates a sludge of organic material that subsequently decomposes into gas. Methane constitutes the vast majority of the resulting gas, and it is then further refined to become pipeline-quality natural gas.

The technology is not new, even though it doesn’t garner the same funding or attention as solar and wind powered energy. Federal grants and loans for anaerobic conversion only equaled $37.2 million through 2009. There are currently over 150 working projects in the United States, but the number and scale of U.S. projects pales in comparison to plants found in heavily subsidizes areas of northern Europe and China.

Microgy, the developer of the project, estimates it can supply the energy needs for 10,000 homes. Contracts were signed to supply energy to customers in Texas and California. Executive Vice-President Michael Hvisdos said, “We’re sustainable without incentives,” claiming the company can produce energy without government subsidies.

Despite the optimism, in July, Microgy’s parent company, Environmental Power, filed for bankruptcy. The financial crisis left the Stephenville project in Limbo. Environmental Power had grown too quickly and borrowed too much money for a variety of projects in Wisconsin, Colorado and California. The failure of climate legislation and a drop in the price of natural gas combined with the debt to create the perfect recipe for financial trouble.

Taking advantage of the bankruptcy-induced low price of $3.3 million, Element Markets purchased the Stephenville plant. The Houston based carbon-trading firm has confidence in the manure-to-energy market. “The biomethane market can provide clean energy and reduced emissions while being commercially successful,” said Element’s chief marketing officer Randall N. Lack.

Environmentally groups are extremely supportive of the movement. Director of the Environmental Defense Fund’s energy program, James D. Marston, said, “I’m very high on that approach.”  Green energy supporters, the Texas community and Stephenville plant employees all hope the new ownership will prove successful.