In July 2012 the Mayor of a small city in west Tennessee decided to lead the town toward a greener future with a gasification plant that would save the city millions of dollars over the life of the project, while also reducing its carbon footprint and diverting waste that would have otherwise been landfilled.
The city is now the showcase of a new waste-to-energy plant that provides power to the city owned Waste Water Treatment facility. The waste-to-energy plant is designed to convert the city’s wood trimmings and sewer sludge to electricity; putting some 4,000 tons of annual waste to work for the community.
Through the process of gasification, this waste produces enough electricity not only to run the plant, but also to dry both the sewer sludge and wood chips that are used as feedstock in the gasifier. The savings that come with implementing a gasification system like this go beyond the cost of energy. Both of these waste streams had previously been landfilled, costing the city about $30 per ton in tipping fees and transportation expenses; both of which are completely eliminated by the gasification plant.
In addition, this plant prevents the release of 450 tons of carbon into the atmosphere each year with the reduction of electrical use for the Waste Water Treatment Plant, as well as the reduction in fossil fuels previously used in transporting the waste to the landfill. This translates to the amount of greenhouse gas emissions expected annually from 80 automobiles or the carbon dioxide emissions from over 35 homes. The gasifier is designed to be modular so it can easily be upgraded to accommodate changing needs in production or feedstock types, providing long-term assurance of its ability to operate.
Construction on the plant began in April 2013 with the plant becoming fully operational in September. The payback on a gasification system like this varies greatly based on economies of scale but savings can become substantial. This city in west Tennessee will see a lifetime savings of over $3 million from its gasification plant and plans to put the money into the city’s park system.
Learn more about waste-to-energy plant at the upcoming Renewable Energy World North America Conference and Expo co-located with Power-Gen International November 12-14 in Orlando, Florida.