Taking advantage of South Dakota’s growing dairy industry, a natural gas utility is working with developers who are turning the industry’s biggest byproduct, manure, into energy for its customers.
In April 2024, NorthWestern Energy accepted the first renewable natural gas into its distribution system at a new interconnect facility north of Brookings, South Dakota.
The RNG used by the Brookings project is sourced from methane that comes from dairy production waste. Before being injected into the system, the RNG is tested for quality and Btu content, verifying that it meets requirements for standard pipeline-quality natural gas.
According to Reed McKee, NorthWestern Energy’s director of transmission and distribution business development and strategic support, the utility will accept approximately 700,000 dekatherms of RNG from the Brookings facility each year, an amount that could serve roughly 10,000 residential customers annually.
The company expects to accept RNG from five more projects that will come online in the state during the latter part of 2024. By 2025, the amount of RNG in its South Dakota system will total 2 billion cubic feet, all sourced from the waste from dairy farms, enough to serve about two-thirds of the company’s South Dakota residential customers.
“RNG offers a chance to secure added pipeline capacity, enhancing economic prospects for the communities we serve in South Dakota,” McKee told American Gas. “With various business advantages, its availability is appealing to major industrial players as they map out their expansion strategies.”
RNG is considered an economic development tool for South Dakota and is part of NorthWestern Energy’s plan to achieve net-zero for the natural gas business—a goal outlined in its Net Zero by 2050 Vision, released in March 2022.
“We are proud to be at the forefront of using RNG, at no additional cost for our customers, in South Dakota,” said NorthWestern Energy President and CEO Brian Bird. “RNG contributes to our sustainable future, provides opportunities for local agriculture businesses and is part of NorthWestern Energy’s net-zero plan.”