Fueling a Revolution
Clean Energy Renewable Fuels, LLC (CERF) is doing something that could revolutionize how we fuel our vehicles. More importantly, its business of converting landfill gas to natural gas is ultimately helping the planet.
By harnessing biomethane gas released from landfills, the California-based company takes an often overlooked renewable energy resource and converts it into natural gas – a fuel source that’s over 85 percent cleaner in carbon emissions, nitrous oxide and particulate emissions than diesel. In a plan to grow its efforts, CERF created the subsidiary Canton Renewables, LLC, which hired Walbridge to design-build a new processing facility at the Sauk Trail Hills Landfill in southeast Michigan. At capacity, the new plant can produce the energy equivalent of 25,000 gallons of diesel per day.
One Person’s Trash is Another’s Energy Source
Biomethane is a gas that’s produced by the breakdown of organic matter in the absence of oxygen. A landfill is an ideal source of biomethane and after it’s processed, it can be used as vehicle fuel.
Prior to construction of the 9,380-square-foot Canton Renewables processing facility in 2012, all the biogas produced at Sauk Trail Hills was being burned off into the atmosphere using a flare. With construction of the Canton plant, Walbridge installed a 150-foot-long, 18-inch underground pipe that taps into the biomethane source and transports it directly into the new facility to be compressed and treated instead of burned. The project scope included integrating various pieces of new process equipment, including blowers, chillers, a scrubber, a regenerative thermal oxidizer and outdoor vessels (two measuring eight feet in diameter and 45-feet tall) that treat and refine the compressed gas. At that stage, it’s sold to local utility companies and released into the natural gas energy grid. Other underground utilities included 1,500-feet of 8-inch water main – 600 feet of which was directionally bored. As a backup, Walbridge also installed one new flare stack to handle off-gas from the production stream and, as an emergency function, to prevent the release of raw landfill gas into the atmosphere.
The new facility is designed to treat raw landfill gas and remove impurities so it meets pipeline quality requirements to be sold as natural gas.
Challenges and solutions
Many owner-initiated changes were introduced during construction of CERF’s plant in Canton, which altered the original cost and scope. In response, Walbridge created an aggressive and highly-detailed schedule to achieve milestones required to support the client’s start-up and commissioning targets. The revised schedule included instituting two shifts for four of the six months it took to complete the project.
The Benefit
At the time of construction, the new plant in Canton was the largest-scale plant of its kind and the only one in Michigan. However, it’s just a small part of a larger plan put forward by CERF. CERF is building a number of similar biomethane plants across the United States to supply renewable natural gas for its parent company, Clean Energy Fuels Corporation (NASDAQ: CLNE). Clean Energy is aggressively implementing a plan to eventually build and supply natural gas fueling stations along major interstates across the county as part of an even broader effort to get logistics companies on board with using renewable natural gas as a primary fueling source.
