Garbage In, Energy Out
Higher oil prices are making waste-to-energy plants attractive again.
Learn where to dispose of household hazardous waste -- everything from paint to computer monitors -- in communities across Florida. There's also information on backyard composting, fire prevention and even Florida hotels and inns that are certified "green lodging" establishments that use recycling, energy conservation and waste minimization.With oil hovering near $60 a barrel and interest in energy independence growing, renewable energy sources are back in fashion. In Florida, the largest source of renewable energy isn't solar or wind or hydro -- it's trash.
Waste-to-energy plants burn almost 4 million tons of Florida garbage each year and generate more than 534 megawatts of power a day, according to the Florida Department of Environmental Protection. That's enough to power about 200,000 homes on an ongoing basis. "We're in the business to dispose of solid waste. One of our byproducts happens to be electricity," says Ben Gilbert, vice president of Montenay Power, operator of the state's largest waste-to-energy plant in Miami-Dade County as well as a smaller plant in Bay County.
Florida's 13 waste-to-energy plants were built in the 1980s and 1990s as alternatives to landfills. Most of the facilities use the "mass burn" method where all trash is incinerated before metals are separated out. Facilities in Miami-Dade and Palm Beach counties use an alternative system of sorting the trash and then burning. Whichever system is used, the trash is reduced by more than 90%, and remaining ash is buried in landfills.
The energy produced during the burning process is typically used to power the facility itself, with the excess power sold on the open market. Montenay's Miami-Dade facility, for example, produces 72 megawatts of power a day and uses 10% to 15% of that to run the plant, says Gilbert. The remainder is sold to Progress Energy.
GARBAGE POWER: Montenay Power operates the largest waste-to-energy plant in Florida. It sells 85% to 90% of the 72 megawatts it produces daily to Progress Energy.In Florida and across the U.S., construction of waste-to-energy plants came to a halt in the mid-1990s after a U.S. Supreme Court ruling that resulted in private trash haulers building regional landfills in rural areas, a solution far less expensive than building waste-to-energy facilities.
The energy production component (as opposed to the garbage disposal component) of waste-to-energy plants may give new life to the industry in the next five years, however, says Gilbert. If gasoline prices continue to rise, it will get more expensive to transport trash to landfills in outlying areas. Also, if waste-to-energy plants can sell their excess electricity to power companies for a higher price, that will decrease the overall cost of operating the plant. Finally, the recently passed federal energy bill includes new tax credits for waste-to-energy and other provisions that require federal agencies to get 7.5% of the energy they consume from renewable sources by 2013.
Already, one Florida waste-to-energy plant is expanding. Lee County's Covanta Lee facility processes 1,200 tons of solid waste each day, generating 39.7 megawatts of energy that is sold to the Seminole Electric Cooperative. The expansion, scheduled to get under way this fall, will let the county burn an additional 600 tons of waste daily and generate another 20 megawatts of energy. Because of increasing difficulties in siting and permitting landfills, the financial advantages of landfills over waste-to-energy plants are diminishing, says Bill Newman, Lee County operations manager for solid waste. "There's very little redeeming value" in a landfill, he adds. "We prefer the waste-to-energy solution."