May 25, 2022

Can We Generate Renewable Energy by Burning Trash? (cnbc.com)

(Via SlashDot) CNBC visited a company that burns trash from a California landfill, and then "harnesses steam to make enough electricity to power 18,000 homes in the area" — which turns out to be part of a surprisingly large industry: A portion of the waste comes from companies including American Airlines, Quest Diagnostics, Sunny Delight and Subaru.... Major retailers like Amazon also use this combustion method to dispose of returns they deem unfit to recycle, resell, or donate....

The U.S. is one of the most wasteful developed countries in the world. Of the record 292 million tons of waste generated by Americans each year, more than half is landfilled, about a third is recycled, and 12% is incinerated at waste-to-energy facilities, according to the World Bank. Online commerce poses a particular problem. Not only are internet purchases breaking records in terms of volume, but roughly 20% of items get returned, which is a higher number than for in-store purchases. Returns solutions provider Optoro says U.S. returns generate an estimated 5.8 billion pounds of landfill waste each year.

But the article also points out that more than half of U.S. states define waste-to-energy as a renewable energy source." Unlike landfills, many governments and non-governmental organizations consider it a source of greenhouse gas mitigation. That includes the U.S. Environmental Protection Agency, where Susan Thorneloe leads research on materials management.

U.S. climate experts say these are the three reasons the burning process produces a net reduction of greenhouse gasses. First, it keeps waste out of landfills, which emit methane that the EPA estimates is 86 times greater than carbon dioxide over a 20-year period. Second, waste-to-energy facilities reduce the need for mining because they recover 700,000 tons of metal each year. And finally, they produce energy, reducing the need to burn fossil fuels.... The steam can also be captured and piped up to a mile away to heat or cool entire buildings, like Target Field in Minneapolis....

The EPA estimates that for every megawatt-hour of electricity generated, waste-to-energy emits an average of just over half a metric ton of carbon dioxide equivalent gasses. Landfills emit six times that, and coal plants emit nearly double.

At least some scientists CNBC spoke to said that air pollution technology has advanced so much in the last two decades that most common toxins have largely been eliminated.