December 16, 2010 | 10
Collect trash, burn it, and then generate electricity. The technology is called Waste to Energy, and it uses our waste streams to produce electricity that can be cleaner than the average kilowatt-hour (kWh) generated in the United States today. A mountain of trash becomes a pile of energy. But, will this domestic renewable resource be able to move beyond its “dirty” reputation to become a larger portion of the U.S. electricity supply?
European countries have embraced Waste to Energy (WTE) as a way to reduce landfill growth as well as dependence on imported fuels. Today, about 400 WTE facilities are operating in Europe, using municipal solid waste as their primary fuel source. In Denmark alone, 29 WTE plants are currently in operation with 10 more on the way. In Sweden, the city of Kristianstad has essentially weaned itself off of fossil fuels in just ten years by replacing these energy sources with the city’s own waste.
In the United States, only 86 (PDF) plants use municipal solid waste as fuel. The amount of trash that these facilities process is dropping – by more than 7 percent (PDF) from 2006 to 2008. And very few new facilities are being discussed.
Why is the United States so far behind?
On the surface, WTE looks like a feasible option in the United States’ search for renewable and domestic energy resources. Today’s WTE technology is safe – assuming you can separate out hazardous materials (like batteries) in the incoming fuel (trash). In areas where tipping fees are high – primarily major metropolitan areas – these facilities can be economically viable without government subsidies.
If deployed nationwide, WTE facilities could reduce the volume of the more than 250 million tons (PDF) of material being thrown away each year by up to 90 percent. If burned properly, the remaining 10 percent would be mostly inert ash. With proper filtering systems in place, WTE facilities can meet and even exceed federal air emissions standards. But, despite these positive environmental attributes, the concept of burning trash does not appear able to shake its “dirty” image in America.
In Austin, Texas, Waste to Energy has been a “dirty” word for more than 30 years. In 1984, voters authorized bond money for the construction of a WTE plant on the edge of the city. But, vocal opposition from environmental activists and resulting runaway project costs led to a showdown that would scuttle the project eight years later. The bad-blood resulting from this ordeal still runs thick today. Even when faced with a 30 percent renewable energy requirement (WTE qualifies), Austin’s city government and local utility (Austin Energy) did not seriously consider any WTE proposals. Instead, city residents receive renewable power primarily from wind farms in West Texas. They will soon buy power from a 100 MW biomass facility that will burn wood chips (not trash), located hundreds of miles to the east of Austin.
A different story has played out on the East Coast – home to high tipping fees and limited land availability for new landfills. In 1984, while Austinites were arguing over the environmental benefits (and costs) of a WTE facility, Baltimore residents were celebrating the opening of the city’s own Waste to Energy plant. Still in operation today – and profitable without government subsidies – the Refuse and Energy Systems Company (RESCO) facility processes about 2,250 tons of trash per day. The facility produces enough electricity to power 40,000 homes, as well as steam for the heating and cooling of local commercial buildings. According to RESCO employees, this no-sort facility has also improved local water quality, because of strict discharge requirements for power generation facilities.
So, why were these experiences so different?
Economics and land availability played significant roles in the decisions in Austin and Baltimore. But, these experiences also showed how WTE’s image problem can be a significant roadblock. Its “dirty” stigma has and could continue to prevent the expanded use of this technology in the United States even under favorable economic conditions. Until Americans become tired of dedicating space for new landfills, the country’s mountain of trash is unlikely to become a pile of energy. And waste will remain an untapped domestic renewable energy resource.
Photo courtesy of: Crane with garbage at Vestforbrænding, courtesy of Vestforbrænding
About The Authors:
Melissa C. Lott is a dual-degree graduate student in Mechanical Engineering and Public Affairs at the University of Texas at Austin. Her work includes a unique pairing of engineering and public policy in the field of energy systems research. Melissa has worked for six years with YarCom Inc. as an engineer and consultant in energy systems and systems design. She has previously worked for the Department of Energy and the White House Council on Environmental Quality for the Obama Administration. She is a graduate of the University of California at Davis, receiving a Bachelor’s of Science degree in Biological Systems Engineering. Melissa is also the author of the blog Global Energy Matters: Energy and Environment in Our Lives.
David Wogan is a dual-degree graduate student at The University of Texas at Austin in Mechanical Engineering and Public Affairs. David’s work includes the integration of engineering, biological, and policy disciplines to assess advanced energy production in Texas. David received his BS in Mechanical Engineering from U.T. Austin in December 2006. David has worked at National Instruments and at the White House Council on Environmental Quality on the Energy & Climate Change Team. David is a currently a graduate researcher with the Webber Energy Group and writes at The Daily Wogan, his energy and sustainability blog.
The views expressed are those of the author and are not necessarily those of Scientific American.