A Danbury firm enabled Oxnard, Calif.-based Gills Onions to create electricity using old onions and a process that mimics how the human body expels gas.
FuelCell Energy of Danbury recently celebrated the installation of two 300-kilowatt Direct FuelCell power plants at Gills Onions. There in California, Gills extracts juice out of the 300,000 pounds of onion waste it produces per day, lets it ferment in an anaerobic digester system, and uses the biogas formed from the process to power the new fuel cells.
The installation, with a price tag of nearly $9.6 million, has an expected payback for Gills of six years and will provide 35 percent to 45 percent of the farm’s electricity needs.
As U.S. officials push for new green technology and tighter pollution standards, a key question for business owners is when does it pay to invest in technology such as fuel cells and what can that mean for investors. Danbury News Times
Machines extract about 30,000 gallons of onion juice that is then sent to a 145,000-gallon holding tank kept at a toasty 95 degrees. Inside, bacteria purchased from an Anheuser-Busch beer brewery produce methane gas by feasting on the carbohydrates in the fermenting juice.
“It’s like a big stomach,” said project manager Bill Deaton.
The gas is purified, dehumidified and compressed, then burned in the fuel cells at temperatures that exceed 1,000 degrees. The 600-kilowatt system produces enough power to operate the plant’s refrigeration units and lighting.
The Gills are also looking into installing a battery at the plant that can store excess electricity from the fuel cells. Reserve energy could be used during peak hours in the summer, when electricity is more expensive. Los Angeles Times
Southern California Gas estimates the system will reduce greenhouse gas emissions by up to 30,000 tons a year.
Gills Onions also will save about $400,000 a year on the cost of hauling the waste to the fields. Gill expects the facility could pay back its cost in five to six years.
Much of the system is automated. Gill said the company, which has about 400 employees, has been able to use current employees for monitoring the system. Some of the work — such as the fuel cell maintenance and digester analysis — is contracted out to companies that provided the equipment.
Though simple to explain, the system is quite complex. The waste has to have the sulphur extracted — what makes you cry when you slice an onion — because fuel cells don’t like sulphur.
The digester needs to be maintained at a specific pH and temperature. And the fuel cells operate at 1,000 degrees Fahrenheit, using a molten carbonate to take the methane gas and generate energy.
All those efforts feed into creating the most efficient system possible, which ties in with the company’s sustainability program and its efforts toward being a zero-waste facility. Ventura County Star
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