July 1, 2009

The Growing Role of Waste-to-Energy in the U.S.

Angela Neville, JD

1.    WTE goes worldwide. Several Asian countries, including Japan and Taiwan, are the global leaders in terms of extensive use of waste-to-energy facilities.  There are 780 WTE plants worldwide processing 140 million tons of waste per year. Courtesy: Waste to Energy Research & Technology Council

Overcoming Dioxin Challenges

In the past, there was a widespread perception that WTE facilities emit a large amount of dioxins, Castaldi noted. "The reality is that the total dioxin emissions from all U.S. WTE plants have been estimated by the U.S. Environmental Protection Agency (EPA) to be at 12 grams TEQ (toxic equivalent) of dioxins," he said. "However, before the Maximum Achievable Control Technology regulations under the Clean Air Act were enacted, they emitted about 10,000 grams TEQ. Now the major source of dioxins in the U.S. comes from backyard barrel burning, with levels at 580 grams TEQ."

According to EPA data, dioxin emissions from WTE generators now account for less than 1% of total dioxin emissions in the U.S., he pointed out (Figure 2).



2.    Dispelling dioxin myths. Due to improved air quality control systems, present-day WTE plants no longer emit high levels of dioxin. Today, U.S. municipal waste incinerators produce less than 1% of known dioxin emissions. Courtesy: Waste to Energy Research & Technology Council

Benefits of WTE Plants

"Most WTE facilities in the U.S. process between 500 and 3,000 tons of waste per day, which provides enough electricity to power 2.8 million homes," he said. "Furthermore, WTE is compatible with recycling and helps to promote resource minimization. For example, WTE plants annually remove more than 700,000 tons of ferrous materials."

Another important advantage of WTE facilities is their positive impact on U.S. air quality, according to Castaldi. He emphasized that today’s U.S. WTE facilities have to meet some of the world’s most stringent environmental standards. They achieved compliance with new Clean Air Act pollution control standards in 2000.

In addition, as stated earlier, WTE facilities produce lower levels of greenhouse gas emissions compared to traditional coal-fired power plants. The EPA estimates that WTE facilities prevent 33 million metric tons of CO₂ per year from being emitted, he noted.

"WTE facilities also save valuable real estate," he added. "They reduce the space required for landfills by about 90%."

Finally, one important fact not to be ignored during this challenging economic period is that WTE facilities provide positive economic benefits. "WTE is a $10 billion industry that employs more than 6,000 U.S. workers, and the annual wages exceed $400 million," he noted.

Future Outlook

In 2007, the U.S. WTE industry had 87 plants that used approximately 29 million tons of MSW as a fuel source. The net generation of these WTE plants totaled approximately 2.6 GW, and there’s potential for an additional 20 GW of WTE capacity in the U.S., which would be equivalent to saving 200 million barrels of oil or avoiding the mining of 70 million tons of coal and 420 million tons of overburden ore, according to Castaldi.

Abundant supplies of MSW make WTE electricity generation well-positioned to be an attractive and dependable source of renewable power in the years ahead.

—Angela Neville, JD is POWER's senior editor.