Renewable natural gas plant planned for landfill in Inver Grove Heights

Landfill biogases will be converted into natural gas under a company's plans to build a new facility — the first of its kind in the state — at the Pine Bend landfill in Inver Grove Heights.

The plant, approved by the City Council on Monday, will be built and run by Forti­star, a White Plains, N.Y.-based investment firm that provides capital to build and manage companies that create "green" energy sources. It is one of about 70 such facilities nationwide.

Republic Services, which owns the Pine Bend Sanitary Landfill, will lease Fortistar the land for the 12,000-square-foot facility. The renewable natural gas plant is expected to be operational by March 2022.

"This technology is new to Minnesota, but not to the rest of the country," said Aaron Janusz, environmental manager for Republic Services, which owns the landfill. "These types of facilities have been in operation for several years."

As landfill waste decomposes, it produces biogas, which is about 50% methane. Once the biogas is collected, the plant will treat it, stripping out everything else so it's pure methane, and send it into the Xcel Energy pipeline. It will then be used to fuel a fleet of trucks at Pine Bend that run on compressed natural gas, a Fortistar spokesman said.

Jonathan Maurer, managing director at Fortistar, said the company has built five such facilities and has three more in the works in Ohio, Florida and now Inver Grove Heights, and helped improve the technology behind it.

"This is a tried-and-true process," he said.

There's been increasing demand for this kind of biofuel both by Congress and by companies interested in reducing their carbon footprint, he said.

Congress passed the Renewable Fuel Standard law, part of the Energy Policy Act, in 2005. It requires petroleum-producing companies to create, sell or purchase "credits" toward renewable energy sources, and this product is one such option, Maurer said, though the amount produced meets only a fraction of the current demand.

Building this facility will allow the company to sell customers "a near-zero carbon imprint — a 99% reduction in carbon compared to diesel — at a price less than diesel," Maurer said.

Maurer noted that the plant's construction will provide about 50 jobs locally and add three permanent positions in Inver Grove Heights, too.

The new facility, which will cost an estimated $40 million to build, will replace another Fortistar facility at Pine Bend that turned methane into electricity but closed several years ago. That plant was inefficient and too costly to run, Maurer said.

Pine Bend landfill is the largest open landfill in Minnesota and encompasses 255 acres in the southeast metro. The plant will be situated on the western 100 acres of the landfill property. The previous facility was in the property's northwest corner.

Currently, landfill gas produced at Pine Bend is being burned off as a flare, said Janusz, adding that he's excited to put it to use as renewable natural gas.

Inver Grove Heights city officials have said previously that they believe the facility will have environmental benefits and be good for the city.

Emily Grubert, a professor of civil and environmental engineering at the Georgia Institute of Technology, said that generally, destroying methane emitted from landfills is useful from a climate perspective.

"If the methane gets into the atmosphere, it's a powerful greenhouse gas," Grubert said.

It's also a safety hazard if it isn't collected and it builds up, she said.

But Grubert said she's critical of renewable natural gas. It's "less carbon-intensive" than using natural gas from fossil fuels, but it's still not as "green" as proponents say, she said.

"At an individual project level, this can be climate-useful, but it's not going to get us to full [carbon] neutrality, basically," she said.

And using renewable natural gas might help maintain the status quo rather than encouraging investment in new, carbon-zero energy sources, she said.

Maurer said he believes the facility and the fuel it produces will improve the environment, locally and on a broad scale.

"We're beginning to make a significant dent in the carbon impact that the transportation industry has," he said.

Erin Adler • 612-673-1781