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

In Stanislaus County, Northern California, next to a landfill, there is a company that handles waste in a completely different way: by burning garbage instead of burying it.

The energy recovery plant operated by New Jersey-based Covanta uses steam to generate enough electricity to power 18,000 homes in the area. Some of the waste comes from companies such as American Airlines, Quest Diagnostics, Sunny Delight and Subaru.

“When a major automaker like Subaru says they are a zero landfill, they have done the reduction, reuse, recycling and leftovers they send to a facility like a waste-to-energy facility,”[ads1]; said Paul Gilman, chief of sustainability. officer for Covanta, which has more than 40 websites worldwide.

Large retailers such as Amazon also use this incineration method to get rid of returns they consider unsuitable for recycling, resale or donating. Amazon told CNBC that they are sending something back to energy recovery as a “last resort”, even though the company refused to say what facilities they use. Covanta said it does not handle Amazon returns.

About 10% of the 270,000 tons of waste that Covanta burns at its facility in Crows Landing, California, a two-hour drive east of San Francisco, comes from companies. The rest comes mostly from garbage collection in nearby municipalities.

Companies represent “the fastest growing part of the business,” Gilman said, as a growing number of companies try to reduce their environmental footprint.

In Covanta’s energy recovery plant, waste is incinerated at temperatures around 2000 degrees Fahrenheit. There are 21 miles of pipes around the burner, where the intense heat converts water into steam that turns a turbine, which drives a generator. The process also creates carbon and toxic ash, but unlike landfills, it does not emit any methane.

The United States is one of the most wasted 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 plants, according to the World Bank.

E-commerce is 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 for in-store purchases. The provider of return solutions, Optoro, says that American returns generate an estimated 5.8 billion pounds of landfill waste each year. Amazon told CNBC that they do not ship any items to landfills.

“There are a number of items that we can not recycle or are not recyclable, for reasons such as legal reasons, or reasons, you know, hygienic reasons, or even product damage,” said Cherris Armor, Amazon’s head of North American returns. “In these cases, we are pursuing energy recovery for these elements.”

The claw picks up around seven tonnes of rubbish and dumps it in the boiler, where it is burned to create energy at Stanislaus County’s waste-to-energy plant on 13 April 2022.

Katie Schoolov

Keep growing waste away from landfills

In parts of Europe and Asia, the picture looks quite different.

Countries such as Japan, Denmark and Germany depend on energy recovery far more than landfills. In the EU, waste incineration doubled from 1995 to 2019.

But burning waste is still a carbon-intensive process, and critics such as Neil Tangri of the Global Alliance for Incinerator Alternatives (GAIA) claim that some countries have relied too heavily on it.

“Denmark now realizes that it burns too much waste, and if it is to reach its greenhouse gas emissions targets, it must reduce waste incineration,” said Tangri.

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

More than half of US states define waste-to-energy as a renewable energy source. Unlike landfills, many governments and NGOs see it as a source of reducing greenhouse gases. It includes the U.S. Environmental Protection Agency, where Susan Thorneloe leads research on materials handling.

When it comes to burning or burying waste, “it was definitely better to burn it because you get energy value from it, you get metals from it, and you do not produce methane,” Thorneloe said.

US climate experts say that these are the three reasons why the burning process gives a net reduction of greenhouse gases. First, it keeps waste out of landfills, which emit methane, which the EPA estimates is 86 times larger than carbon dioxide over a 20-year period.

Second, waste-to-energy facilities reduce the need for mining because they recycle 700,000 tonnes of metal each year. And finally, they produce energy, which reduces the need to burn fossil fuels.

“For every ton of garbage you burn, you save tons of CO2 that you would otherwise make by, for example, burning fossil fuels,” said Marco J. Castaldi, director of the Earth System Science and Environmental Engineering Program at City. College of New York.

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

While landfills can utilize energy from rotting organic material, they are far less efficient for production purposes. Landfill gas generates enough electricity for 810,000 US homes per year, compared to 2.3 million homes powered by far fewer waste-to-energy plants.

Covanta Sustainability Manager Paul Gilman stands in front of the Stanislaus County Center on April 13, 2022, where waste incineration generates enough electricity to power 18,000 homes in the area.

Katie Schoolov

Closely monitored spills and toxic ash

Covanta’s official data shows that the emissions coming out of the stack in the Northern California facility are far below US federal standards. This is because Covanta purifies toxins from its combustion gases using an intense filtration process, with activated carbon and limestone scrubbers.

“The air pollution control systems, they were not present on old-fashioned incinerators, are the subject of many people’s annoyance,” Gilman said.

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

Dioxin and mercury are some of the most dangerous emissions that worry critics of the process. GAIA points to plants as one in the Netherlands, which regulators found emitted so much dioxin that it contaminated grass and chicken eggs in the surrounding area.

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

But other researchers say that air pollution technology has come so far in the last two decades that most common toxins have been largely eliminated.

“The amount of dioxin emitted from all waste-to-energy plants over the course of a year is less than a fraction of what is generated from forest fires,” Castaldi said.

Nevertheless, the combustion process produces a lot of toxic ash, which Covanta tests regularly to ensure that hazardous materials are not able to leak out.

“Fortunately, we have always passed our tests,” Gilman said.

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

“There is probably more municipal solid waste ash that we can use, but because of the negative connotation, I just do not see it happening,” said Thorneloe from the EPA.

“Arguments about last place”

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

There are about 1,450 active landfills today, compared to 76 waste-to-energy facilities, said Bryan Staley of the Environmental Research Education Foundation. This makes it difficult for many companies to participate.

“We have to transport it by rail halfway across the United States to get it there, because you usually find most of the waste power plants in the northeastern part of the United States, in Florida and Minnesota and then a touch of plants elsewhere,” Staley said.

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

“It’s a real question of why California and why most of the United States for that matter is so in love with our landfills,” Gilman said. “But it is a fact. Sometimes we have a lot of land, something Europe did not have that luxury with.”

But turning waste into energy is a lucrative business. Each tonne of waste generates $ 20 to $ 30 in revenue, according to the EPA. Covanta was on a big rise before a Swedish investment company took the company private last year in a deal of 5.3 billion dollars. In fact, incineration is one of the most expensive commercial ways to generate energy and manage waste, more than double the cost of sending it to a landfill.

Giant companies like Amazon can often negotiate special prices. Burning waste instead of sending it to landfills helps them meet their sustainability goals. Tangri said that it can also help with optics.

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

Tangri said that companies and consumers need to focus more on really cutting emissions through reduction, reuse and recycling.

“You’re arguing for last place,” Tangri said. “We know that the important thing to do is to keep so much material and especially organic material out of the waste stream … If Amazon returns were repackaged and sold to people at a discount instead of being thrown away, we would not have to have this question of whether it is better or worse to bury plastic or burn it. “

Amazon does not provide a lot of specific details. But the company has added programs to ensure that more returns are resold as used, refurbished or liquidated. And while there is no target date for the high targets, Amazon says they are “working toward a goal of zero product disposal.”

SEE: How Amazon is planning to fix the multi-billion dollar return issue

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