Trial of biofuels at power plant in New York

Can biofuel crops help displace conventional fuels at power plants? The New York Power Authority (NYPA) wants to know.

NYPA conducted two days of testing at its Charles Poletti Power Project in Queens late last month, blending a biofuel from soybean oil with conventional fuel oil to generate electricity.

"To the best of our knowledge, this was the first such application at a large power plant, and the largest use of biofuels on any single occasion in the U.S.," said Timothy S. Carey, NYPA president and chief executive officer.

Over the two days of testing, the Poletti project used a total of 100,000 gallons of biofuel blended with 900,000 gallons of No. 6 fuel oil, at partial and full generating capacity levels. Varying concentrations were used for the blended fuel, in degrees ranging from 5 to 20 percent, to monitor combustion effectiveness and emissions. The data from the tests, which will be fully developed for a study being prepared by the Power Authority and the Electric Power Research Institute (EPRI), showed some efficiency gains from the mixed fuel, compared with combustion of only conventional fuel oil, along with reductions in emissions.

This includes carbon dioxide (CO2) since bioenergy crops re-absorb CO2 emitted when biofuels are burned, creating a cycle that is essentially carbon neutral.

Poletti operators blended the conventional fuel oil and soybean-derived biofuel at the plant site themselves since the quantity they required exceeded the mixed fuel amounts that could be purchased. The Power Authority installed a system of tanks, pipes, pumps, instrumentation and other equipment for delivering the blended fuel, in varying concentrations, to the plant’s 18-story boiler, where temperatures reach more than 3,000 degrees Fahrenheit, to produce steam to generate electricity.

An interdepartmental team of NYPA staff members, consisting of employees in power generation, fuels operations, research and technology development, environmental programs and other groups, spearheaded a two-year program leading to the biofuel tests.

“This really was a collective effort drawing on the expertise of a number of our professionals,” said Paul Tartaglia, NYPA regional manager at Poletti, who was an early proponent of the testing. “It all began a couple of years ago when a few of us took two five-gallon buckets over to the Poletti chemistry lab to mix small amounts of blended fuel, so we’ve come a long way.”

The Charles Poletti Power Project ordinarily burns clean natural gas as its primary fuel, with oil as a backup. The 885 MW project operates at the same East River site in Astoria where the Power Authority placed in service a new natural gas-fueled power plant, in December 2005. That facility, among the most efficient and cleanest fossil-fuel plants, uses combined-cycle technology to capture hot gases normally lost in the generation of power to provide additional amounts of electricity and lower emissions.

Independent researchers and other utilities witnessed the Poletti combustion tests.