Duke Energy using North Carolina-based renewable natural gas
A Duke Energy power plant is using renewable natural gas from North Carolina-based hog farms to produce electricity – the first application of the technology from in-state farms.
Sometimes called directed biogas, the Optima KV project in Duplin County captures methane gas from the hog waste of five local farms. Using more than 42,000 feet of in-ground piping, the methane is moved to a central location where the gas is cleaned and converted to pipeline-quality natural gas.
The project injects the renewable natural gas into the Piedmont Natural Gas system which transports it to Duke Energy's Smith Energy Complex in Richmond County where it is used to produce electricity. Optima KV completed its interconnection to Piedmont Natural Gas last week.
Historically, renewable natural gas has been used by smaller, on-site generators that are connected to the overall energy grid. Using Duke Energy's larger, more efficient plants allows more renewable energy to be created with the same amount of renewable natural gas.
The project will help Duke Energy satisfy state swine waste-to-energy mandates under the Renewable Energy and Energy Efficiency Portfolio Standard law in North Carolina. Under this law, Duke Energy must generate 0.20 percent of its retail sales from swine waste by 2023.