We know that these days, with so many past and current advances in clean technology, most of the garbage that society generates is no longer waste – it’s a potentially valuable resource. We can use waste to make fuel, building materials, car parts, waxes and lubricants, park benches and a seemingly endless list of other products. And while true it’s not the highest-value use of waste, we can also use it to generate electricity through waste-to-energy.
How much electricity? That’s what researchers at Columbia University’s Earth Engineering Center set out to measure in a study published in July, recognizing that some waste simply can’t be recycled or converted into fuel economically.
Their conclusion: If all municipal solid waste that was landfilled in 2011 were to be fed into waste-to-energy (WTE) plants, “it could generate enough electricity to supply 13.8 million households,” or roughly 12 per cent of all U.S. households. “In addition, if the steam turbine exhaust of the WTE plants were to be used for district heating, as is done in Denmark and some other northern European countries, the waste steam could provide district heating for 9.8 million homes.”
It’s a big number, and one that reflects the current state of recycling in the United States. The fact is, roughly two-thirds of all municipal solid waste in the U.S. still finds its way to landfills, and that excludes commercial and industrial waste, according to the study.
Much more could be done to push recycling and composting rates up, but if non-recycled waste were burned instead in a modern WTE facility, every ton would displace 0.4 tons of coal, the study estimates. In other words, it has the potential to reduce U.S. coal production by 10 per cent.
It would also reduce total U.S. greenhouse gas emissions by 2.1 per cent, the study found.
