While the return of gas prices to a more palatable level has stifled public discontent for now, it's hard to predict when the next oil shock may occur. And when it does, Rhode Island, Newport Biodiesel will still want your grease.
Since January, Newport Biodiesel LLC (newportbiodiesel.com) has been converting an average of 20,000 gallons of used restaurant cooking oil per month into vehicle fuel and home heating oil at its production facility on the outskirts of the Newport Naval Base.
Newport Biodiesel provides barrels to its suppliers, the restaurants fill them with grease, and Newport Biodiesel then sends a truck to collect it. As Amanda Marcello, a manager at Eleven Forty Nine Restaurant in Warwick attests, "There is no out of pocket expense" associated with a restaurant's role in grease supply.
Nat Harris, the company's production manager, estimates the amount of used restaurant oil available per year in Rhode Island to be about 2 million gallons. With average oil-to-biodiesel yields in the range of 93 percent, a nearly equivalent volume of fuel could theoretically be produced.
Presently, collected oil is processed in batches of 1000 gallons per day. Harris says his company plans by the end of winter to upgrade to a continuous process known as cavitation "that will do five gallons per minute, as long as you feed it" — making outputs of 1 million gallons per year possible.
At that point, the primary limitation on output will be the volume of waste oil that can be brought in. Newport Biodiesel's immediate goal is to collect enough oil to produce 350,000 gallons of fuel per year. It is actively seeking to enlarge its roster of suppliers to help them reach that total.
Because Newport Biodiesel doesn't pay for its "feedstock," its costs are relatively fixed, mainly the cost of collecting the oil (using a truck powered by the firm's own biodiesel, of course), plus the costs of processing: straining food particles and removing excess moisture from the oil, regenerating "tired" oil using methanol and sulfuric acid, and turning oil into diesel using methanol and potassium hydroxide.
When petroleum prices approached $150 per barrel earlier this year, Newport Biodiesel was selling its product for between 20 and 80 cents less per gallon than petroleum-based diesel.
"This summer, we would produce 1000 gallons, put it in the tank, and it would be gone within an hour, because we were cheaper," says Harris. Based on recent production costs, he estimates that Newport Biodiesel can compete on price with petroleum diesel when petroleum prices exceed $90 per barrel.
Producing and then burning biodiesel from waste oil is a carbon-neutral process. And much of what is strained out in the initial processing stage can be used as compost!
Harris is realistic about the ultimate scope of biodiesel from waste oil.
He doesn't see it as a silver bullet solving all of Rhode Island's energy needs, as there is not enough waste oil available to replace the state's total diesel consumption, but as one component of what he terms a "silver buckshot" strategy that uses a range of alternatives to replace petroleum.
By collecting and converting as much local waste oil as they can, the team at Newport Biodiesel intends to see that biodiesel plays as large a role in petroleum replacement as is possible.