Dairy is the largest industry in the state of Wisconsin and it can also be a major source of biofuel, according to GreenWhey Energy, based in Turtle Lake.

Dairy businesses end up with a large amount of wastewater, which is full of nutrients. At present, this wastewater is used to fertilize land but nutrient-rich runoff causes algae bloom, which is dangerous to aquatic systems. That is why the company came up with a method that feeds dairy wastewater into biogas reactors and allows the production of energy that is used to provide power locally, Gizmodo reported.

RELATED: US scientists develop quick method to convert algae into crude

The GreenWhey Energy plant is being ramped up at the moment and is currently operating at about half-capacity. However, once the project is completed, the plant will be able to process 500,000 gallons of wastewater and produce methane that could provide power to 3,000 homes. But methane is not the only by-product of the process — there is also leftover sludge, which can be dried and used as a fertilizer, with its transportation in a solid state much cheaper and more convenient than as a liquid, the website noted.