Story here.

 Energy Savers: Biodiesel helps run diverse fleet

By Adam Arnold, Staff Writer

The Town of Cary is trying to put the squeeze on its fuel use.

That means getting the most out of the more than 500,000 gallons of fuel used by more than 1,500 engines.

That fleet includes everything from “chainsaws to fire trucks,” said Mike Bajorek, the town’s public works director. “It’s a very diverse fleet.”

Fuel economy is among the criteria the town considers when it purchases vehicles, Bajorek said.

However, many vehicles, such as police cars and other sedans, are purchased through a state contract, and Bajorek said he did not know how fuel economy is weighed in state purchasing.

The bulk of Cary’s wheeled fleet travels about 3.5 million miles per year, according to the town’s budget.

That total does not include several types of vehicles, such as the town’s solid-waste fleet, that have their operation measured in hours rather than miles, Bajorek said.

Cary has moved its 169 diesel vehicles from straight petroleum diesel to B20 biodiesel, Bajorek said.

The B20 designation means that the fuel is a blend of 20 percent biodiesel — diesel fuel made from plants or waste oil rather than petroleum — and 80 percent petroleum diesel.

“It’s purely trying to reduce our dependency on oil,” Bajorek said.

The move to biodiesel came after a spike in fuel prices following Hurricane Katrina in late summer 2005.

“We’ve been watching our fuel usage,” Bajorek said.

Data from recent Cary budgets bear that out. In fiscal year 2006, which ran from July 1, 2005 to June 30, 2006 and included Katrina and its aftermath, the town used 528,209 gallons of fuel.

Estimates for fiscal year 2007, which ended June 30, 2007, show an increase to 535,000 gallons, or 1.3 percent, even though the fleet grew by 26 vehicles.

A similarly small increase in fuel usage, along with a similar increase in fleet size is expected for fiscal year 2008, which ends June 30.

Diesel vs. Biodiesel
Like gasoline, diesel fuel is refined from petroleum. The key differences, according to howstuffworks.com, are that diesel fuel needs less refining than gasoline and has more energy content per the same volume. Those characteristics, combined with the more efficient diesel engine, lead to better mileage.

Diesel has fueled the American trucking industry and a significant portion of the passenger vehicles in other parts of the world for decades. With American consumers becoming more conscious of fuel economy and technologies improving to refine cleaner burning diesel, many passenger-car manufacturers are beefing up diesel car and light truck offerings for the United States.

Unlike petroleum-based diesel fuel, biodiesel can be distilled from plants, such as coconuts, hemp, soy beans, safflower, peanuts, rape seed and algae, or processed from used cooking oil.

Biodiesel and diesel is often combined. The common B20 is 20 percent biodiesel and 80 percent petroleum diesel.