A biodigester facility in Middleton has been repurposed to create green energy from an unexpected source. With the support of Dane County, EnTech Solutions partnered with Northern Biogas to repurpose an anaerobic biodigester facility to create clean renewable natural gas (RNG) using agricultural waste from four local dairy farms. RNG from cow manure can reduce greenhouse gas emissions up to 400 percent when used to replace traditional fossil fuels.