"Gills Onions is using onion juice from its processing plant to power a 600 kilowatt fuel cell electricity generation unit that will slice $700,000 in energy costs from the bottom line.
Gills Onions, one of the nation’s largest onion growers and processors, estimates the $9.5 million system will pay for itself in about six years, with the help of about $3 million in government and utility incentives, reports the Los Angeles Times.
The system is good for the 14-acre processing facility’s carbon footprint, too. It should eliminate 30,000 tons of CO2e emissions annually.
Additionally, converting waste onion material to energy will save up to $400,000 a year on disposal costs.
How it works:
One of Gill’s best-selling products is a line of sliced and diced fresh-cut onions. Because about 40 percent of each onion is unused in the process, the company generates some 150 tons of waste a day.
Machines are able to extract 30,000 gallons of onion juice, which is then piped to a 145,000-gallon holding tank. The tank, which is kept at 95 degrees, has bacteria purchased from an Anheuser-Busch brewery. The bacteria consume the carbohydrates in the fermenting juice, produce methane gas, according to the article.
The system takes methane from fermented onion juice and converts it to energy that is burned in two fuel cells on-site. Learn more about Gill’s sustainability efforts here.
More and more fresh produce growers are finding ways to save energy in their operations.
Recently, Houweling’s Hot House, a British Columbia-based greenhouse tomato and cucumber grower, put into place what it calls the world’s first carbon-neutral commercial greenhouse for fresh produce. The greenhouse uses a 1.2 megawatt solar array to run the facility, also generating heat to let the greenhouse operate with greater efficiently during cooler weather." See source here.