How Amazon, American Airlines and Subaru burn waste to make energy

In northern California’s Stanislaus County, next to a garbage dump, there’s a company that manages waste in a very different way: by burning garbage instead of burying it.

New Jersey-based Covanta’s energy recovery facility uses steam to make enough electricity to power 18,000 homes in the area. Some of the waste comes from American Airlines, Quest Diagnostics, Sunny Delight and Subaru, among others.

“When a major automaker like Subaru says they’re out of landfill, they’ve reduced it, reused it, recycled it, and sent what’s left over to a facility, like a waste-to-energy facility,” said Paul Gilman, chief of sustainability. officer for Covanta, which has more than 40 offices around the world.

Major retailers such as Amazon also use this incineration method to discard returns they deem unsuitable for recycling, resale or donation. Amazon told CNBC it is returning some of its energy recovery as a “last resort,” though the company declined to say what facilities it uses. Covanta said it does not handle Amazon returns.

About 10% of the 270,000 tons of waste Covanta incinerates at its Crows Landing, California plant, two hours east of San Francisco, comes from corporations. The rest comes largely from waste collection in nearby municipalities.

Companies are responsible for “the fastest-growing part of the business,” Gilman said, as an increasing number of companies try to reduce their carbon footprint.

At Covanta’s energy recovery facility, waste is incinerated at temperatures around 2,000 degrees Fahrenheit. There are 21 miles of pipes surrounding the combustor, where the intense heat converts water into steam that spins a turbine, which drives a generator. The process also creates carbon and toxic ash, but unlike landfills, it doesn’t emit methane.

The US is one of the most wasteful developed countries in the world. Of the record 292 million tons of waste generated annually by Americans, more than half is landfilled, about a third recycled and 12% incinerated in waste-to-energy facilities.

Online trading poses a particular problem.

Not only do online purchases break records in terms of volume, but about 20% of items are returned, which is a higher number than in-store purchases. Returns solutions provider Optoro says returns in the US generate an estimated £5.8 billion worth of landfill waste each year. Amazon told CNBC it does not send items to landfills.

“There are some items that we can’t recover or are not recyclable, for reasons like legal reasons, or reasons for, you know, hygiene reasons, or even product damage,” said Cherris Armor, Amazon’s head of North America. returns. “In those cases, we do aim for energy recovery for those items.”

The claw picks up about seven tons of trash and dumps it into the boiler, where it’s burned to make energy at Stanislaus County’s waste-to-energy plant on April 13, 2022.

Katie Schoolov

Keep Growing Waste Out of Landfills

In parts of Europe and Asia, the picture is very different.

Countries like Japan, Denmark and Germany rely much more on energy recovery than on landfills. In the EU, waste incineration has doubled from 1995 to 2019.

But incinerating waste is still a carbon-intensive process, and critics such as Neil Tangri of the Global Alliance for Incinerator Alternatives (GAIA) argue that some countries have come to rely on it too much.

“Denmark is now realizing that it is burning too much waste and if it is to meet its greenhouse gas emissions targets, it will have to reduce waste incineration,” Tangri said.

In the US, the first incinerator was built in New York in 1895. A decade later, the city used it to generate enough electricity to light the Williamsburg Bridge.

More than half of US 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 reduction. So is the US Environmental Protection Agency, where Susan Thorneloe leads research into materials management.

In terms of burning or burying waste, “it was definitely better to burn it because you get energy value from it, you get metals out of it, and you don’t produce methane,” Thorneloe said.

US climate experts say these are the three reasons why the combustion process produces a net reduction in greenhouse gases. 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 plants reduce the need for mining as they recover 700,000 tons of metal annually. And finally, they produce energy, reducing the need to burn fossil fuels.

“For every ton of waste you burn, you save a ton of CO2 that you would otherwise create by burning a fossil fuel, for example,” said Marco J. Castaldi, director of the Earth System Science and Environmental Engineering Program at the City. New York University.

The steam can also be captured and routed a mile away to heat or cool entire buildings, such as Target Field in Minneapolis.

While landfills can extract energy from decaying organic matter, they are much less efficient for production purposes. Landfill gas generates enough power for 810,000 U.S. homes per year, compared to 2.3 million homes powered by far fewer waste-to-energy facilities.

On April 13, 2022, Covanta Chief Sustainability Officer Paul Gilman stands in front of the Stanislaus County Switchgear Plant, where the incineration of waste generates enough electricity to power 18,000 homes in the area.

Katie Schoolov

Carefully controlled emissions and toxic ash

Public data from Covanta shows that emissions coming out of the chimney at the Northern California plant are well below U.S. federal standards. That’s because Covanta cleans toxins from its combustion gases using an intense filtration process, using activated carbon and limestone “scrubbers”.

“Air pollution control systems were not present on old-fashioned incinerators, the object of many people’s wrath,” Gilman said.

The EPA estimates that for every megawatt hour of electricity generated, waste-to-energy emits, on average, just over half a ton of carbon dioxide equivalent gases. Landfills emit six times as much and coal-fired power plants almost double.

Dioxin and mercury are among the most dangerous emissions that have concerned critics of the process. GAIA points to facilities like the one in the Netherlands, which, according to regulators, emitted so much dioxin that it contaminated grass and chicken eggs in the area.

“Despite the air pollution control and monitoring equipment, there are still many toxins in that plume, from particulate matter to heavy metals, lead, mercury, arsenic and cadmium,” Tangri said. “Here in the US, our monitoring systems and standards are much lower than in Europe.”

But other scientists say air pollution technology has come so far over the past two decades that most common toxins have been largely eliminated.

“The amount of dioxin emitted from all waste-to-energy plants in one year is less than a fraction of what is produced by wildfires,” Castaldi said.

However, the combustion process releases a lot of toxic ash, which Covanta regularly tests to ensure that hazardous substances cannot leach out.

“Luckily, we always passed our tests,” Gilman said.

In Europe, facilities separate the more toxic “fly ash” and use the safer “bottom ash” to make things like concrete for road construction. In the US, the fly and bottom ash are usually mixed together, making it too toxic to be reused, so it is buried on site in a monofill.

“There’s probably more municipal solid waste that we can use, but because of the negative connotation, I just don’t see that happening,” said Thorneloe of the EPA.

‘Fight for last place’

Landfills in the US are big business. While Castaldi estimates that waste-to-energy is a $10 billion industry, the total waste-to-energy industry is estimated at $208 billion. Landfill companies such as Waste Management and Republic Services have outperformed the market since 2015, enabling them to keep prices low as they grow.

There are currently about 1,450 active landfills, compared to 76 waste-to-power plants, said Bryan Staley of the Environmental Research Education Foundation. That makes it difficult for many companies to participate.

“We have to get it by rail halfway across the United States to get it there because you usually find most of the waste-to-energy facilities in the northeastern United States, in Florida and Minnesota and then a few facilities elsewhere,” Staley said.

Transport creates an extra carbon footprint for companies that choose energy recovery over landfill. The Covanta facility is one of only two energy recovery facilities in California. Europe has more than 400.

“There’s a real question about why California and why most of the US, by the way, are so enamored with our landfills,” Gilman said. “But it’s a fact. It happens that we have a lot of land, something that Europe didn’t have that luxury with.”

But converting waste into energy is a lucrative business. Each ton of waste generates $20 to $30 in revenue, according to the EPA. Covanta made a big upward move before a Swedish investment company took the company off the stock market last year in a $5.3 billion deal. In fact, incineration is one of the most expensive commercial ways to generate energy and process waste, more than double the cost of sending it to a landfill.

Large companies such as Amazon can often negotiate special rates. By incinerating waste instead of sending it to landfills, they can meet their sustainability goals. Tangri said it can also help with optics.

“If Amazon sends all of its returns to a landfill, someone could go to the landfill to see them, and that would be a horrific picture,” Tangri said. “When you burn something, you hide the evidence.”

Tangri said businesses and consumers should focus more on actually reducing emissions through reduction, reuse and recycling.

“You’re arguing for last place,” Tangri said. “We know it’s important to keep as much material as possible, especially organics, out of the waste stream… If Amazon returns were repackaged and sold to people at a discount rather than thrown away, we would haven’t. to have this question of whether it’s better or worse to bury or burn plastic.”

Amazon doesn’t provide many specifics. But the company has added programs to ensure more returns are resold as used, refurbished or liquidated. And while there’s no target date for its lofty goals, Amazon says it’s “working toward a goal of zero product removal.”

WATCH: How Amazon plans to solve the billion-dollar return problem

Leave a Comment

Your email address will not be published.