Project to use landfill gas to generate power
Within the next year, gas generated by the regional landfill will be converted to fire an electric generator, putting 'green' power on the grid, an official said.
The landfill, located on the line between Clay and Oktibbeha counties and operated by Golden Triangle Regional Solid Waste Management Authority, will be home to the first landfill-gas-to-electric project in Mississippi, said the solid waste authority's executive director, Jimmy Sloan.
"We'll be making green power and putting it on the grid," Sloan said.
Landfill gas is approximately 50 percent methane and 50 carbon dioxide, he said.
Sloan explained the method by which the gas will be captured and converted to use.
Equipment will be used to remove the moisture from the methane and compress it slightly before being used as fuel for the generator. Landfill gas contains high levels of moisture, which makes the gas difficult to burn and is corrosive.
Officials installed a gas collection control system in 2009 at the landfill on the part of the landfill which is filled out, he said. The system will be expanded as other parts of the landfill are finished. The system consists of gas extraction wells which have valves.
Then, the wells are fed to a header pipe. This pipe is connected to a blower flare skid, basically pulling the gas out of the landfill by use of a vacuum, Sloan said.
Currently the gas gets burned off at the flare, he said. "What will be doing with the new project is diverting it from the flare to the generator," he said, adding there may be times both the flare and the generator could be burning.
The flare project was completed to generate carbon credits to reduce the carbon footprint, but doing just flaring wastes the energy value in the gas, Sloan said.
The generator will be on a site on landfill property in Clay County.
TVA will purchase the power created by the 999 kilowatt-per-hour capacity generator via 4-County Electric Power Association. This would generate enough to power in a 24-hour period to cover the electricity 18 typical family homes would use in a month, according to 4-County officials.
TVA approved the project Oct. 8.
Bids will be opened Friday on the generator.
"It's got about a seven-or-eight month lead time so it's critical to get it bid early," Sloan said.
Officials hope to get the generator operational in August.
The project is taking place under the TVA Generation Partners program, officials said in a statement.
“TVA is excited this project will add Mississippi renewable energy to the TVA system. These projects help TVA and 4-County provide local renewable energy while supporting the local economy,” said David Sparks, Mississippi manager of energy efficiency and demand response for TVA.
“The electric power industry is at a crossroads right now, trying to find ways to reduce carbon emissions while continuing to provide enough electricity to meet growing demand. Renewable power will play a bigger and bigger role in the way electricity is generated. We are glad to be able to be a part of something that will help our members and their communities as well as the environment,” said Joe Cade, 4-County CEO and general manager.
Sloan also made comments in the statement.
"The Board of Commissioners and staff of the Solid Waste Authority are very excited for the opportunity to partner with TVA and 4-County through the Generation Partners program. ... This project involves a significant investment for the Authority but likewise has the potential to provide a significant return," Sloan said.
He continued: "All revenue streams assist in our efforts to maintain a low tipping fee for disposal of solid waste, and have a direct impact on the costs borne by the businesses, industries and citizens of the six-county Golden Triangle region. Maintaining low cost helps the businesses within the region to remain competitive any time, but especially during uncertain economic times. The Board has demonstrated vision and forward thinking in allowing pursuit of such a major project and should be commended for their efforts.”
The solid waste authority serves Clay, Lowndes, Oktibbeha, Choctaw, Noxubee and Webster counties.