Witnessing a Waste-to-Energy Revival

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The U.S. municipal solid waste (MSW)-to-energy industry has had its ups and downs but is on the upswing once again. Government-issued tax incentives and the need for alternative energy sources make it an attractive endeavor and economic alternative to landfills in communities striving to be self-sufficient.

The first waste-to-energy combustion facility in the U.S. went on line in New York in 1898, according to the Energy Information Administration, but it was not enough to initiate rapid growth. About 80 years later, in 1975, the first commercial-scale, utility-grade MSW-to-energy plant in the country went on line in Saugus, Mass., built by Wheelabrator Technologies Inc. That was the start of an industry here that had been successful in Europe for years. "The Saugus Marsh dump was nearing the end of its life," says David Beavens, vice president of finance for Wheelabrator. "And there was a need for a new, viable solution for waste disposal." The plant still operates today, processing 1,500 tons of MSW per day from 10 nearby communities, serving about 750,000 people and providing electricity for about 47,000 households through Saugus General Electric.

After that plant went on line, more than 100 plants were built around the country as the industry ballooned beginning in 1978, according to the EIA. "If you think about that timing, you had the first gasoline shortage; the first energy shortage," Beavens recalls. "So there was a move to find alternative sources of energy. And that created interest in things like waste-to-energy."


The Genesis of the Industry

"A combination of forces converged in the late 1970s, early 1980s that really were the genesis for this industry at that time," Beavens says. Those forces were the search for waste disposal solutions, legislated tax incentives and the desire for alternative energy sources as energy prices rose. "Rising energy prices are very favorable for the waste-to-energy business," he says.

Dwindling solutions for waste disposal also proved favorable to the onset of the industry. "There was a local need to provide long-term, predictable waste disposal for constituents," Beavens says. The country was moving away from dumps, as tighter regulatory compliance led to the end of the town dump concept. Increases in tipping fees also led to the demise of many landfills, according to the EIA.

During the energy shortage in the '70s, Congress passed the Public Utility Regulatory Policies Act, which stabilized prices for alternative sources of energy. The act, passed in 1978, made it mandatory for utilities to purchase electricity from qualifying facilities, defined as "cogeneration or small power production facilities that meet certain ownership, operating and efficiency criteria established by the Federal Energy Regulatory Commission pursuant to (PURPA)," according to the EIA. It also mandated that the price paid to MSW facilities for electricity be equal to the utility's avoided cost of energy and capacity. As a result, MSW qualifying facilities received a higher price for their power than they might have received otherwise.

Boosted by these incentives, Wheelabrator led the way into an MSW-to-energy industry in the U.S., Beavens says. "We're very proud of that," he says. Previously, many communities ran trash incinerators that reduced the volume of trash by combustion before dumping it. But the incineration plants did not recover energy, used expensive fuel and offered little or no pollution control. Waste-to-energy provided a next-generation technology that recaptures energy, using trash as fuel, with no extra fossil fuels, Beavens says. Wheelabrator's combustion systems are compliant with air regulatory requirements and extend landfill lives by reducing the volume of waste by 90 percent from incoming raw material to residual ash, Beavens says, and 70 percent to 75 percent by weight.


A Roadblock

Unfortunately, the growth spurt didn't last and the same factors that jump-started the industry reshaped to slow it down in the mid '90s. "The industry hit a wall," Beavens says. The investment in tax credits expired, the energy markets were deregulated and the development of large, environmentally sound Subtitle D landfills made that type of disposal more plentiful and less expensive.

Many companies began to consolidate and those that had small plants sold their operations to larger companies. "Companies came and went," Beavens says. "You saw a lot of consolidations and companies exiting the industry." For the most part, plants already in operation continued, but some under new management. "There were a few plants here and there that closed, but not too much on the waste-to-energy side," he says. Wheelabrator and Covanta Energy became the primary waste-to-energy providers in the country, he says. It was then that Wheelabrator was acquired by its parent company Waste Management Inc.

For those companies that did manage to stay in business, new development and growth were stagnant. "So, you retrench," Beavens says. Wheelabrator changed its focus from expansion to excelling and polishing its environmental practices, safety programs and operational efficiencies, he explains. "We improved our operations and technology such that today, we're excellent in our operations."


A Bevy of Plants

Today, Wheelabrator operates 16 waste-to-energy plants in the U.S., along with five independent power plants with pollution controls and two ash landfills. Its waste-to-energy process uses combustion at temperatures of greater than 2,000 degrees Fahrenheit.

"Basically, it's a series of steps that every other step reciprocates," says Peter Kendrigan, plant manager at the company's Westchester County facility in Peekskill, N.Y. The 60-megawatt plant was built in 1984 and supplies electricity for about 55,000 homes from 2,250 tons of MSW per day in a county of 850,000 people, according to Kendrigan. It actually has enough capacity to supply 88,000 homes, according to the company's Webs site. Its capacity makes it one of the largest Wheelabrator waste-to-energy plants.

In Westchester, trucks deliver the waste to a receiving building, where most dump their loads into a pit, while some are randomly chosen for inspection. Those trucks dump their waste on the floor, where it's sorted to ensure it contains no unacceptable material. "It's very rare that we find something unacceptable," Kendrigan says. "With a plant of this age, most of the haulers have been here long enough that they're familiar with the rules."

Two large overhead cranes take the trash from the pit and feed it into Wheelabrator's water wall boiler. Inside the boiler, the trash sits on Von Roll Holding AG grates, heavy metal plates developed by Von Roll, a worldwide electrical machinery developer. The grates move back and forth, transporting the trash through four boiler zones. First, the trash is dried out by injecting air underneath it. Then, it's combusted in zones two and three and in zone four, all that's left are the noncombustibles. The energy generated in the process is sold to Consolidated Electric.

Because of Westchester County's aggressive recycling program, the waste that comes into the facility is ready to process and needs no pretreatment, Kendrigan says. "But once it's in the process, we do add some things to make it cleaner and environmentally friendly," he adds. A powder-activated carbon is added for mercury removal, lime slurry is sprayed into the system to remove sulfur dioxide and carbon, and urea cleans out nitrogen oxide. Hydrocarbons, organic compounds and dioxin are controlled by the high temperatures in the combustion furnaces, and sulfur dioxide and hydrochloric acid are neutralized and made harmless by flue-gas scrubbers, he adds. Trace metals and particulates are collected in fabric filters. "Nothing escapes a waste-to-energy plant unless it has been purified by heat or treatment," Kendrigan says. "High burning temperatures and cleansing processes remove more than 95 percent of pollutants from refuse that enters the facilities."

"A significant thing about the facility is that the air in the receiving building is drawn in through large fans and we use that in combustion inside of our boilers," Kendrigan says. It creates negative pressure inside the building so odors and dust accumulated during dumping don't escape the building.

Some of Wheelabrator's plants produce and sell steam and electricity, and some just sell electricity, depending on the local needs and economics. "It's not economical to sell steam in this community," Kendrigan says. The plant sits in an industrial area in Peekskill, next to a fairly major highway. Piping to transport the heat would have to snake underneath the highway to get to the community, he explains.

Residents of Peekskill are welcoming of the plant and Wheelabrator's technology, Kendrigan says. "Westchester enjoys a very good relationship with the community," he says. "The community itself has an extremely positive reaction to the facility." It helps that it creates jobs for 66 locals. "All of the employees are very proud of Westchester and Wheelabrator," he adds. "We're proud of what we do."


Unique Stories

While most of Wheelabrator's plants were built in response to waste disposal issues in the communities, each has a unique story of its own, Beavens says. His career with Wheelabrator started in 1988 at the Gloucester County plant in New Jersey. The local landfill in Gloucester County had historically been a dumping ground for the city of Philadelphia, he says. The large landfill, which he calls "a dump, in the true sense of the word," sat in the middle of the county. It brought land values down and hindered economic development, so county officials decided as early as 1980 that they wanted to become self-sufficient. "They were going to neither import waste nor export waste," he says. They kept the dump alive long enough for them to build their own solid waste infrastructure, which included Wheelabrator's waste-to-energy plant. "So those came on line by the end of the 1980s, early 90s and they became self-sufficient," he says.

The Gloucester plant processes up to 575 tons of MSW per day from the county of 257,000 people. The 14-megawatt facility has the capacity to supply electricity for up to 15,000 homes.


Getting Back on Track

Today, Beavens sees factors emerging in the MSW-to-energy market similar to those that gave rise to it in the '70s and '80s: alternative energy is desirable, energy is expensive and tax incentives abound again to build new plants. Also, landfills generally are located farther away from communities, requiring long hauls for trucks loaded with garbage to dump. "While the landfills are still plentiful, they tend not to be located close to population centers that generate the trash," he says. As fuel prices rise, trucking becomes more expensive and those trucks emit pollutants into the air along their routes. Waste-to-energy facilities are sited within or close to population centers, reducing truck traffic and transportation costs, he says.

"So if you think about today, while a little bit different, you're seeing similar forces," Beavens says. These forces are coming together once again, reviving the familiar attraction to the industry. Beavens says he's seen the change evolving in just the past two years. Currently, about 87 waste-to-energy facilities operate in the U.S., managing 93,000 tons per day, or 13 percent, of the nation's MSW and producing 2,700 megawatts of energy, according to Wheelabrator.

New interest in the industry, and in Wheelabrator's process in particular, comes in monthly from cities all over the world, Beavens says. "Domestically, we see a lot of interest," he says. "Internationally, we see a great deal of interest." The company is pursuing several projects in the U.K. and recently entered into a joint venture with a company in China. The government there expects to build more than one waste-to-energy facility per month, Beavens says, adding that the country has a very aggressive growth plan.

With so many new ventures on the horizon, Beavens sees promise in a comeback for the industry. "I think it's in its early stages of growth and I expect it will continue," he says. BIO

Lisa Gibson is a Biomass Magazine associate editor. Reach her at [email protected]
bbiinternational.com or (701) 738-4952.