Companies and local governments in Canada, Alaska, Hawaii, Honduras, and other places have been experimenting with fish-based biodiesel for years, and some commercial enterprises are using and selling it profitably.
This should come as no surprise to anyone who remembers that before the petroleum age dawned, the world used whale oil for light and heat. In fact, petroleum was an eco-friendly alternative when first discovered, as several whale species were roaring into the fast lane on the road to extinction. Don't worry about fish fuel speeding up the depletion of the oceans, though -- all the fuel described here is made from oil left over from fish processing.
Using this waste oil for fuel has long been standard practice. According to the Alaska Energy Authority (AEA), "[fish] processors produce approximately 8 million gallons per year of fish oil from as a byproduct of fish meal plants. Much of the oil is used in the process as boiler fuel for drying the fish meal..." At first they started simply mixing the raw fish oil with diesel fuel. This worked, but raw fish oil is about 6 percent less energy-dense than diesel, and some newer engines cannot use raw fish oil.
In 2004 the AEA partnered with the Hawaiian firm Pacific Biodiesel to make biodiesel out of the fish oil; now production is more local. Biodiesel from fish and waste cooking oil is used in Denali National Park, both in stationary generators and in vehicle engines; the energy agency even has a brochure about it.
The amount of fish biodiesel being used is minuscule compared to availability, however.
Using this waste product could have other environmental benefits. As noted in the New Agriculturist last year:
In Nova Scotia, Canada, a company that mostly sells the omega-3 fatty acids found in fish oils as nutrition supplements began using waste oil to make biodiesel for its' own operations, and then went on to selling it. Ocean Nutrition Canada (ONC) sells biodiesel to a local gas station chain, which blends it into B20 before selling it. Oddly, you can't find anything about it on ONC's website, but you can read about it at Canada's Eco-Efficiency Centre, as well as some other sites.
Most of the activity in fish biodiesel has been centered in Alaska and Canada. Why? Because they have some very isolated coastal cities where fish oil is the most abundant feedstock for biodiesel. As the public-private partnership West Coast Collaborative puts it: "Alaska has very limited viable sources of biodiesel due to very limited waste cooking oil, nonexistent agricultural oil crops, and high import transportation costs for biodiesel produced elsewhere."