Leveraging landfill gas

Since 2003, landfill gas (LFG) from the WM-owned Palmetto Landfill in Wellford, South Carolina, has been used to power a BMW Manufacturing facility in Spartanburg, the largest of BMW Group’s plants. Through BMW’s partnership with renewable energy company Ameresco, more than 9,200 tons of CO2 emissions have been reduced each year.  

In April, BMW announced an eight-year extension to its 20-year partnership with the Framingham, Massachusetts-based company. Ameresco had previously constructed a 9.5-mile pipeline from the Palmetto Landfill to the Spartanburg plant, which the extended partnership will continue to utilize. LFG powers approximately 20 percent of the plant’s total energy requirements. 

Founded in 2000 by CEO George Sakellaris, Ameresco is a renewable energy asset developer, owner and operator. Some of the company’s solutions include energy efficiency upgrades to lighting, water, heating and cooling; distributed generation of electricity (DEG) projects, such as solar and renewable natural gas (RNG); energy infrastructure; financial operations; energy supply management; and energy analytics and supply. 

“Ameresco doesn’t manufacture any widgets or technology,” says Michael Bakas, the company’s executive vice president. “[Our clients] help us identify what their goals are… and we figure out solutions to help them attain their goals. Then, we go out in the market, and we source [the] best available technology to [integrate] into a functioning system.” 

Bakas describes the company as “agnostic,” adding that because Ameresco does not promote a particular product, it can explore different approaches to design solutions for its clients. 

Since the company’s inception, it has expanded to 60 regional offices located throughout the United States, Canada and Europe and has more than 1,500 employees.  

Bakas says the company has engaged in approximately 40 LFG projects over the years, with the BMW plant being one of its earliest. A green power plant project in Chicopee, Massachusetts, has Plant Spartanburg beat for first.  

Ameresco’s contract with BMW is an Energy as a Service (EaaS) partnership where BMW pays Ameresco for the LFG produced at the Palmetto Landfill without an upfront capital investment. 

“The BMW project is not a power generation project per se,” Bakas explains. “It’s what we call a direct use project, where we take the energy and we deliver it to the customer to be used in their existing systems.” 

After a one-year development process, Ameresco began construction on the 9.5-mile pipeline from Palmetto Landfill to the Spartanburg plant in 2002. Bakas says the pipeline was constructed under two rivers, an interstate highway and a railroad.  

“When we got close to BMW, we hit a lot of rock. We were breaking drill bits regularly so that made it a little bit challenging,” he adds.  

After approximately nine months, the pipeline was finished. Once completed, the company began capturing methane gas through dozens of gas extraction wells at the Palmetto Landfill for treatment. This treatment includes removing moisture and impurities and compressing the methane at the landfill’s Recovery Compression Station. The methane then travels via pipeline to the BMW facility. 

BMW had four existing 1.25-megawatt gas turbines sitting unused on the property, which Ameresco retrofitted to accept the larger volume of LFG needed to power the facility. In 2009, BMW replaced the original four turbines with two new turbines, which the company says increased its electrical output from 14 percent to nearly 30 percent. 

Today, the project cogenerates electricity and hot water for Plant Spartanburg, with BMW purchasing the equivalent of 4,000 cubic feet per minute of LFG for use in its turbines from Ameresco.  

Ameresco employs onsite operators to perform necessary maintenance and ensure the pipeline is clear of contaminants. 

Over the years, Ameresco’s partnership with BMW has expanded to include other LFG projects. In 2011, BMW announced the launch of an LFG-to-hydrogen project to fuel its material handlers.  

Project partners included the Advanced Technology Institute, Summerville, South Carolina, a subsidiary of the South Carolina Research Authority (SCRA); the Gas Technology Institute, Des Plaines, Illinois; the South Carolina Hydrogen and Fuel Cell Alliance, Columbia, South Carolina; and Ameresco. According to an Environmental Protection Agency (EPA) case study, Ameresco served as the subcontractor to SCRA, providing business case analysis and onsite engineering support for the technical validation portion of the project.