May 26, 2023. The Western Virginia Water Authority and Roanoke Gas Company entered into a cooperative agreement last year to produce commercial quality renewable natural gas (RNG) from biogas produced at the Roanoke Regional Water Pollution Control Plant. This RNG product, the first of its kind in the Commonwealth, necessitated construction of a digester gas conditioning system and interconnect facility at the Water Pollution Control Plant (WPC Plant). Representatives from the Authority, Roanoke Gas and the community officially opened this facility with a ribbon cutting on May 25 at the Roanoke Regional WPC Plant.
Biogas, also known as digester gas in wastewater treatment, is a mixture of methane (63%) and carbon dioxide (37%), produced as a waste by-product of the anaerobic digestion treatment process as bacteria consume the organic solids that are removed earlier in the wastewater treatment process. A separate yet complimentary project undertaken by the Western Virginia Water Authority to rehabilitate and upgrade five of the primary anaerobic digesters will increase the volume of biogas that can be produced at the facility. That project is about 70% complete with several digesters rehabilitated and currently producing brown gas for delivery to the gas treatment system. When all digesters are complete the process will produce between 288,000 and 317,000 cubic feet of gas per day. At full buildout, the digesters will produce and the digester gas conditioning system will treat a biogas design flow of 550,000 cubic feet per day (cfd) to create commercial quality RNG.
“The Roanoke Regional Water Pollution Control Plant has a history of improving our environment through advanced wastewater treatment and energy recovery. While this gas has been used as a fuel source within the facility over the years, the digester upgrade and gas conditioning project allows the broader community to benefit from this beneficial and renewable fuel source.” according to Michael McEvoy, Executive Director Western Virginia Water Authority.
“We are thrilled to have the opportunity to partner with the Western Virginia Water Authority on such an impactful and needed project,” stated Paul Nester, President and CEO of Roanoke Gas Company. “Our shared desires to improve the environment, utilize the best technology and most importantly, serve this community, have spurred approximately $16.5 million dollars of combined investment and added a much needed source of safe, clean natural gas.” Roanoke Gas projects this new supply source will provide enough natural gas to heat 500 homes on a cold, winter day.