"Anaerobic Digester" Turns Manure into Renewable Energy

A Vermont dairy farmer is getting more from his cows than just milk.

The Goodrich Family Farm in Salisbury, Vermont spans more than 2,400 acres, with 900 milking cows, and they’re partnering with Wellesley, Massachusetts-based Vanguard Renewables to host the largest “anaerobic digester” east of the Mississippi River.

Vanguard Renewables’ anaerobic digester will combine more than 100 tons of manure and 180 tons of organic food waste daily into renewable natural gas, and the RNG will travel by pipeline to Middlebury College.

“One of the key components of Middlebury’s Energy 2028 plan is to shift the College completely to the use of renewable energy,” said David Provost, Middlebury’s executive vice president for finance and administration. “The digester is fundamental to this change.”

The actual conversion process isn’t quite as exciting (or appetizing).

According to John Hanselman, CEO of Vanguard Renewables, “We take it up to about 104 degrees so we cook it like a stew,” which sounds absolutely peachy.

In addition to annual lease payments, the Farm gets free heat and high-quality liquid fertilizer for hosting the digester and providing one half of the … raw materials.

When it’s complete in June 2020, the digester will produce 180,000 Mcf per year. (Mcf = 1,000 cubic feet of renewable natural gas.), and Middlebury College will buy 100,000 Mcf of the gas from Vanguard, while Vermont Gas will buy 40,000 Mcf, and Vanguard will retain 40,000 Mcf.

Read more here: https://www.renewableenergymagazine.com/biogas/middlebury-college-and-project-partners-celebrate-groundbreaking-20190821