By Ashley Fletcher Frampton
Published Feb. 16, 2009
Berkeley County is moving forward with plans to extract gas, electricity and other energy sources from an array of wastes that converge at the county landfill near Moncks Corner.
Along with two private partners, the county is developing what some describe as an “energy park” at the landfill site on U.S. Highway 52.
One component calls for creation of electricity or natural gas from the methane emitted from mounds of decaying trash. Plans also call for wood waste to be used as fuel for a biomass burner that generates electricity. Another initiative would take used restaurant oils and create pellets that burn like coal.
Each of the green energy technologies has been tested in other parts of the country or world, said Colin Martin, executive director of Berkeley County Water and Sanitation Authority. But officials think Berkeley County’s 1,100-acre landfill site will be the first place where they are all happening on a single site.
The large amount of land at the site is one reason for its energy-generating potential, Martin said.
Funding and revenues uncertain
The plan is expected to cost between $125 million and $130 million, Martin said. Some of that would come from two private companies that are partnering with the county.
County officials will pay some of the costs, but they are still seeking funding to make it all work. They hope the federal economic stimulus bill or other federal green energy initiatives will play a role.
Also unknown at this point are financial benefits for the county. But so far the project looks economically viable for all stakeholders — the biggest challenge for green energy ventures, Martin said.
Starting with methane
Even without all the dollars and details in place, the county is moving ahead on some pieces of the plan. Removing gas from the landfill is a first step.
Methane gas, a natural byproduct of rotting material in landfills, is a pollutant, a so-called greenhouse gas. The county plans to install 75 special wells to draw gas, including methane, out of the trash mounds and flare it. Burning the methane prevents it from polluting the air, said Mark Schlievert, director of solid waste.
The water and sanitation authority has about $3 million to pay for the wells. Bids are in, and work could start in March.
The well equipment will track how much gas is removed, allowing Berkeley County to sell carbon credits for the environmental cleanup, Schlievert said. The credits are traded like stocks and would bring in new revenue.
Longer-term plans are to generate electricity from the gas via turbines, or to convert the landfill gas into cleaner natural gas and sell it. Electric utilities such as Santee Cooper are potential buyers of the landfill gas, county officials said.
Though it has no deal in place with Berkeley County, Santee Cooper has been purchasing landfill gas from four sites across the state and using it for electricity generation since 2002, said Marc Tye, vice president of conservation and renewable energy for the utility.
The electric cooperative has set a goal that 40% of its energy generation by 2020 should come from sources that do not emit greenhouse gases. Accordingly, Santee Cooper would consider buying renewable energy sources from the landfill project, Tye said.
More methane, faster
Landfill plans also call for construction of two large cylinders, called anaerobic digesters, to speed the rate of methane production. Because of their temperature and humidity levels, the digesters can produce methane gas from rotting matter in two weeks. Nature takes about three years, Martin said.
Turning the landfill’s normal methane emissions into natural gas would create energy equal to 3.1 million gallons of gasoline annually, he said. The anaerobic digesters would add to that total the equivalent of 800,000 gallons.
Converting landfill gas to natural gas is not a new technology; Berkeley County would join nearly 500 such projects across the country, according to the U.S. Environmental Protection Agency.
All of the capital required for the methane conversion projects totals about $17 million, Martin said.
In January, Berkeley County Council approved a memorandum of understanding with Green Energy Partners, a Greenville company that would be involved in several components of the landfill project, including the anaerobic digesters.
Another joint project is a biomass burner that would produce electricity.
Wood waste at the landfill would fuel the biomass burner. The burner would heat treated water from the county’s wastewater treatment facility, producing steam that would turn a turbine and generate electricity. Dan Page, president of Green Energy Partners, said he hopes to start building the facilities by mid-2009.
The company targeted Berkeley County for the projects because of its progressive attitude, its growth and its landfill space, Page said.
“By collocating facilities around the landfill, you’re not infringing on other residential areas or properties,” he said.
Martin estimates that the planned biomass burner could power 23,000 homes continuously. Another benefit is that the burner would present a productive use for treated wastewater instead of sending it into the Cooper River.
At about $97 million, the biomass burner is the most expensive part of the energy park. But it also has the largest potential return, Martin said.
EcoPlus approached Berkeley County with a business proposal after learning that its landfill is the only one in the Lowcountry that accepts restaurant cooking wastes, said John Baker, the company’s vice president of business development.
EcoPlus dehydrates fats, turns them into a granular substance and forms pellets that burn with an energy value that’s similar to coal but cleaner, Baker said.
Restaurants are required to dispose of their fats, and Berkeley County accepts and treats them, though doing so isn’t easy, Martin said. So the county welcomed the opportunity to eliminate a waste that gums up its facilities.
The pellets could be a source of electricity for Santee Cooper, Baker said, or as power for the landfill’s biomass burner.
EcoPlus has proved the process, which it recently patented, at its pilot facility in Charlotte. The Berkeley County site, which Baker calls an energy park with several anchors, would be the company’s first commercial facility.
Work should get started in the first half of this year, he said.
Baker said he is confident his innovative product will be in demand. “The renewables market is going to be significant over the coming decade.”
Reach Ashley Fletcher Frampton at 843-849-3129.