Trash Power

Tapping Power From Trash

Phil Marino for The New York Times

RECOVERY WORK an enclosed flare at the landfill burns off gas that has an insufficient methane content for effective energy production.

Buried in airless pockets deep inside landfills, the organic matter in these great mounds of waste is consumed by bacteria that give off gas rich in methane, increasingly used to generate electricity and heat.

In fact, power from landfill methane exceeds solar power in New York and New Jersey, and landfill methane in those states and in Connecticut powers generators that produce a total of 169 megawatts of electricity — almost as much as a small conventional generating station. The methane also provides 16.7 million cubic feet of gas daily for heating and other direct uses.

There is ample opportunity for energy-producing projects at more landfills, according to the Environmental Protection Agency’s Landfill Methane Outreach Program and officials and groups in the three states. As scouring for alternative energy intensifies, landfill methane is getting more attention from state, federal and local governments together with private energy and waste-management companies, landfill owners and energy entrepreneurs.

If it is not captured, the E.P.A. says, landfill methane becomes a greenhouse gas at least 20 times more potent than carbon dioxide, the principal greenhouse gas, when it rises into the atmosphere. The agency estimates that landfills account for 25 percent of all methane releases linked to human activity.

As a result, capturing methane at former and active landfills is a global housekeeping benefit as well as an important alternative energy niche.

In New York, power from landfill methane far exceeds solar power and is led by the 72-megawatt capacity of Covanta’s American Ref-Fuel incinerator in Hempstead, the largest Long Island plant making energy from refuse burning. In New Jersey, power from landfill methane surpasses both solar and wind power.

The Environmental Protection Agency lists more than 51 operating landfill methane projects in the three states, 7 under construction and 23 shut down. It lists opportunities at more than 90 other sites, most in New York and several on Long Island.

Landfill methane powers generators that produce 83 megawatts of electricity in New Jersey, 80 in New York and 6.1 in Connecticut, and more landfill energy could be on the way. Waste Management, the largest garbage hauler and landfill operator in the country, is in the midst of a five-year, $400 million plan to build methane-to-electricity projects at 60 landfills nationwide. It already has a project at the landfill in New Milford, Conn.

At some landfills, methane is not harnessed but is burned off, or flared, keeping it from the atmosphere but wasting its energy potential. That is changing.

“As the price of energy has increased, there is more interest in getting some energy production out of these landfills as opposed to simply flaring,” said Janet Joseph, director of clean energy research and market development for the New York State Energy Research and Development Authority.

Ms. Joseph and others acknowledge that energy production from landfill methane, while desirable, will go only a short way toward meeting overall energy needs.

Still, available and anticipated incentives — including renewable energy credits, tax breaks and carbon offsets, linked with market forces and a regional initiative to reduce greenhouse gas emissions — are increasing interest in methane capture and use.

In New Jersey, more than half of captured landfill methane is now used. The state’s largest project, at the 600-acre Ocean County landfill in Manchester, generates 20 megawatts, the E.P.A. said. Projects are in operation at more than 20 New Jersey landfills, under construction at 3 and possible at 8 others, E.P.A. data show.

On Long Island, the Wehran Energy Corporation project at the 8.1-million-ton Brookhaven Town landfill, which closed to garbage in 1996, has pumped 350,000 megawatt-hours of electricity into the power grid over the past 30 years. Wehran’s president, Fred L. Wehran Jr., said the Long Island Power Authority pays 8.5 cents per kilowatt-hour for power the company delivers to its grid.

With gas from the closed landfill declining, Mr. Wehran said he was seeking ways to make power from the lower-methane gas coming from Brookhaven’s adjacent and still operating landfill for construction and demolition debris. “I’d like to use every cubic foot of gas,” he said, “because once it’s gone it’s gone.”