Climate change deniers are an easy (and appropriate) target when searching for reasons why there has not been more movement around climate issues in this country. But, surprisingly, some of the most troubling stumbling blocks to reducing greenhouse gases don’t come from Tea Party members or Republicans, the groups most often in the denial camp. Instead, urban liberals and left-leaning environmental groups who oppose burning municipal solid waste to produce energy are standing in the way of a technology that could have profound effects on GHGs.

When new waste-to-energy plants are proposed in California, for example, they run into buzz saws [pdf] of liberal opposition. Plans to increase the volume of waste burned at a Minneapolis WTE facility have been blocked for four years, and the issue recently divided the Democratic candidates for mayor. From New York to Massachusetts to Rhode Island to Pennsylvania to Maine, opposition has delayed or stopped WTE plants across the nation, largely in liberal-controlled urban areas.

But the opposition is misguided. Today’s WTEs are not your granddaddy’s trash burners, and some liberal groups, like the Center for American Progress, are starting to look at the actual science [pdf] and reevaluate long-held assumptions in light of new information and increasing concern over climate change. When they do, they are finding that today’s WTE plants look surprisingly good for the environment and for fighting climate change [pdf].

Reduce, Reuse, Recycle — Then What?

Americans generate about 390 million tons of trash every year — as much as 7 pounds per day for every man, woman and child. Waste ranks with energy, food, population and the economy as one of the biggest issues humans need to tackle to create a sustainable world. The U.S. recycles and composts about 94 million tons of that waste, or roughly 24 percent, but could do much more.

Waste management hierarchy

Waste Management Hierarchy. Image courtesy of Shawn Otto.

But, even if the U.S. doubled its rate of recycling, there would still be hundreds of millions of tons of post-recycled, post-composted solid waste. What you do with it is the question, and there are two options: dump it in a landfill or burn it/gasify it for energy.

Concern that WTEs reduce recycling rates does not appear to be borne out by the evidence, which shows that they actually tend to be associated with increased recycling effort.

Liberals, overwhelmingly, are choosing to dump, which science shows is the most polluting alternative. Because of liberal opposition, almost no WTEs have been built in the U.S. in 20 years, despite the classification of WTE as clean energy by the EPA and 31 state environmental agencies.

Things are very different in green-conscious Europe. While the U.S. has just 89 WTE facilities, Europe [pdf] has around 420 and is building more. Northern Europe, the most environmentally conscious part of the continent, is also where the most WTEs are located.

WTE construction in the U.S. is being held back by fears that burning trash will cause people to reduce their recycling effort [pdf] or will put dangerous toxins into the environment. But are those fears supported by the evidence?

Recycling and WTE Are Complementary

Of course recycling should be maximized in order to remove all recyclables and compostables before waste is disposed of in a landfill or a WTE facility. But concern that WTEs reduce recycling rates does not appear to be borne out by the evidence, which shows that they actually tend to be associated with increased recycling effort.

The five European nations with the highest recycling rates — Germany, the Netherlands, Austria, Belgium and Sweden — have among the highest WTE usage, to the point that they have reduced landfill use to less than 1 percent of their waste. Sweden even competes to import waste. While this is questionably desirable, it does not appear to have reduced the country’s recycling effort;  its rate of recycling is higher than 22 other European nations.

Graph of the percent of waste to energy, recycling/composting and landfilling in the United States and Europe

The United States if far behind Europe on recycling and waste to energy. Image courtesy of Shawn Otto.

In America, by contrast, where environmental groups frequently portray the issue as an either/or choice [pdf] between recycling and WTEs, both rates are much lower. A whopping 69 percent of U.S. municipal solid waste winds up in landfills. As in Europe, though, communities in the U.S. that do have a WTE plant show higher recycling rates than the national average.

WTE community average recycling rate vs. national average

Finally, recycling itself is not without waste. For example, recycling of mixed paper leaves a 15 percent residue that still has to be disposed of somehow.

Clearly, recycling and WTE can and do go hand-in-hand in a responsible waste management plan, and co-promotion by environmental groups would likely increase both WTE and recycling, both of which are preferable to landfilling in the waste management hierarchy.

Clean Air Technology Cuts Emissions To Near Zero

While trash burners once did put dangerous toxins into the air, in the past 10 years WTE pollution control technology has become so advanced that the most common and dangerous toxins have been almost completely eliminated [pdf], something that the environmental groups who still oppose WTEs rarely mention.

WTE emission reductions

Under the Clean Air Act, WTE facilities are required to use the most up-to-date air pollution control technology available so emissions are safe for the health of both humans and the environment. This new equipment must meet or exceed the EPA’s Maximum Achievable Control Technology [pdf] standards. WTE plant emissions are far below the limits the EPA set as safe, and they get better all the time. The Minneapolis WTE facility, for example, uses a combination of tools and procedures to control its emissions, including injecting air into the boiler to control nitrogen oxide emissions; passing combustion gases through a baghouse containing a series of filters to remove particulate matter (ash), metals and dioxins; and injecting activated carbon into the exhaust gases to control mercury.

WTE emissions

Opponents of WTEs often make misleading arguments [pdf] based on emissions data or policy decisions from 2000 or prior, before the MACT technology was put into place, instead of acknowledging WTE’s impressive results. Or they use EPA data stating that trash burning is the largest source of cancer-causing dioxins. This is true, but the data refer to the uncontrolled backyard barrel burning of trash, and specifically not to WTEs.

These are the sort of anti-science tactics — quoting old data, misattributing data or results, cherry picking data — that have been used by climate change deniers.

The Nontoxic and Widely Used Ash

WTEs reduce the volume of trash by about 90 percent, leaving about 10 percent in the form of ash that still needs to be landfilled unless it can be used elsewhere. Opponents often argue that the ash is toxic, but the EPA developed a test called the Toxicity Characteristic Leaching Procedure that tests the ash with an acidic liquid, causing any of 40 identified contaminants — in other words, reactive metals such as cadmium — to leach out. If these metals are found in amounts greater than a fraction of a percent, the ash is considered hazardous. Scientists have tested ash from every WTE facility in the U.S. over the course of several years, and the tests have consistently shown that the ash is nonhazardous.

It turns out that while WTEs do emit greenhouse gases, they emit far fewer GHGs on a ton-for-ton basis than landfilling. In fact, 31 state pollution control agencies now class WTEs as renewable energy.

Consequently, about 3 million tons of concrete-like ash or more than one-third of WTE residue is being reused annually for and in a number of things, including roadbed material, landfill cover, asphalt, artificial reefs and cement blocks. WTE operators are actively looking for other ways to reuse the ash renewably instead of disposing of the balance in landfills. Mixing it into concrete is one solution that offsets the production of cement, which otherwise accounts for 5 percent of the world’s carbon emissions.

WTEs Fight Climate Change

Burning trash puts large amounts of carbon dioxide into the atmosphere, and with the atmosphere already at a dangerously high 400 parts per million — higher than it has been in at least 600,000 years — to do so, opponents reason, will only compound the climate change problem. But it turns out that while WTEs do emit greenhouse gases, they emit far fewer GHGs on a ton-for-ton basis than landfilling. In fact, 31 state pollution control agencies [pdf] now class WTEs as renewable energy. To understand why, consider a ton of post-recycled, post-composted trash in either of two scenarios: landfilled, or burned for energy.

Carbon dioxide concentration at Mauna Loa Observatory

First, roughly 53 percent of post-recycled, post-composted trash is still derived from organic materials and so is part of Earth’s carbon cycle anyway. Burning it does not increase the atmosphere’s carbon load, while burning the remaining 47 percent, which is derived from petroleum carbon, prevents other, worse emissions. According to the EPA [pdf], every ton of garbage processed at a WTE facility actually prevents approximately 1 ton of emitted CO2 equivalent from going into the atmosphere.

This is because landfills are the U.S.’s largest emitter of methane, a very potent greenhouse gas. According to the Intergovernmental Panel on Climate Change’s Fourth Assessment on Climate Change, in a 20-year window methane was shown to be 72 times more potent a greenhouse gas than CO2. Capped landfills now have the technology to capture methane, but only about 34 percent [pdf] of that methane is actually used to generate electricity. The rest leaks away or is flared off, and nothing at all is captured for the first few decades a landfill sits open. 

Next, no municipality gets 100 percent recycling participation. Post-recycled trash still contains millions of tons of metals that are sent to landfills. At a WTE facility, those metals are automatically captured and recycled by the facility as a part of its normal post-combustion filtration process. This saves the time, materials, energy, emissions and environmental disruption of mining for an equivalent amount of new minerals. The WTE operator Covanta Energy recycled 415,000 tons of ferrous metals and 16,800 tons of nonferrous metals in 2012 alone — enough steel to build 28 Brooklyn Bridges and enough aluminum to produce more than 1 billion beverage cans.

The aluminum that is reclaimed by WTEs from the already post-recycled waste is particularly important. Recycling one ton of aluminum prevents a whopping 13.7 tons of GHG emissions, compared to 4.3 tons for 1 ton of office paper and 2.5 tons for newspaper. Recycling a ton of ferrous metal prevents 1.7 tons of GHG emissions. None of this is recaptured when a truck tips its load into a landfill.

Additionally, WTE facilities are sited close to where waste is generated, in or near urban areas. This eliminates much of the carbon emitted by hauling waste to a distant landfill. In 2011, New York City spent more than $300 million transporting its trash by train and truck — roughly 12,000 tons per day — to landfills as far as 300 miles away, emitting tons more carbon and wearing down roads and vehicles in the process. In some cases, the U.S. is now even exporting its waste to developing countries, vastly compounding its carbon contribution.

The high temperature of WTE combustion completely destroys the chemicals, rendering them inactive and ensuring cleaner lakes, rivers and water supplies.

WTE facilities also generate heat and electricity, avoiding the burning of fossil fuels for those same purposes. For example, the Minneapolis WTE facility currently generates enough electricity to power 25,000 homes, and enough steam to heat 1,500. Their proximity also means less heat and electricity are lost in transport. And, according to EPA studies, burning municipal solid waste in WTEs emits less CO2 per megawatt-hour than burning fossil fuels, including natural gas. New gasification technologies coming online promise even greater energy capture and lower emissions than WTE incineration.

Chart of CO2 by fuel type

Cleaning up U.S. Lakes and Rivers

Leachate is a hazardous tea created when rain percolates through garbage. Landfills capture this leachate and pump it to a treatment facility, where pollutants are removed through biological and chemical processes before it is discharged into public waterways. But these treatment facilities rarely have the expensive reverse osmosis filters necessary to capture pharmaceuticals and other bioactive chemical products. These agents are turning up in groundwater throughout the U.S. and polluting even remote lakes and rivers. Their presence affects fish and other aquatic species, and they are now found in several municipal water supplies that are drawn from waters polluted with pharmaceuticals.

WTE facilities provide a safe way to destroy pharmaceuticals and other bioactive chemical products that are otherwise disposed of in landfills or that people flush down the toilet. The high temperature of WTE combustion completely destroys the chemicals, rendering them inactive and ensuring cleaner lakes, rivers and water supplies, and fewer pharmaceuticals and bioactive agents entering the food chain and affecting public health.

Time For a Change

So with all these benefits — efficiency, clean energy, reduced greenhouse gases, reduced transportation and road repair, reduced mining, freeing land space otherwise lost to landfills, protecting groundwater and public waters, keeping the food chain cleaner, recycling metals — why haven’t U.S. liberals, who control the politics in many metropolitan areas where WTEs should be built, been supportive of them as they have been in Europe? The answer lies in the history of the American public’s views toward science.

Suspicion of corporations and of hidden dangers to health or the environment have become core, and often unquestioned, assumptions of the liberal U.S. politics that grew up with environmental science and the environmental movement. But these days there is a growing rift between the science and the movement in areas related to energy, climate and waste management. While liberals are justified in their concern about the hidden dangers that pollution can pose, in the case of WTE plants that view has not kept up with the times. This has led to policies that are less effective than those in other countries when it comes to managing waste and fighting climate change.

It’s time for a change. American liberals and environmentalists who care about climate change need to reexamine the science and get behind expanded recycling and WTE programs. Fortunately for the sake of our children, a few bold leaders are starting to do just that. View Ensia homepage

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