'Dirty Secret': Made-in-China Solar Panels Produce 3 Times More Carbon Emissions Than UN Claims: Study

Workers install solar panels at the construction site of the 40MW photovoltaic on-grid power project in Huai'an, China, on June 11, 2018. (VCG/VCG via Getty Images)

An analysis by a nonprofit research group claims that the United Nations organization on climate change has been drastically underestimating the carbon intensity of Chinese-made photovoltaic cells.

Environmental Progress, a nonprofit organization co-founded by investigative journalist Michael Shellenberger, in collaboration with The Blind Spot and Italian analyst Enrico Mariutti, argue in a recently released report that Chinese-made solar panels are about three times as dirty—in terms of carbon emissions during their production—as what has been claimed by the Intergovernmental Panel on Climate Change (IPCC), the U.N. body for assessing climate change science.

"People say solar panels don't produce carbon emissions, but they do. And now, a major new investigation by Environmental Progress, drawing on the research of @enricomariutti, finds that solar panels made in China produce at least 3x more carbon emissions than IPCC claims," Mr. Shellenberger wrote in a tweet on July 24.

Specifically, the IPCC claims that the carbon footprint of solar panels—most of which are made in China—is about 48 grams of carbon dioxide (CO2) per kilowatt-hour (kWh). But Environmental Progress said in a bombshell report that research carried out by Mr. Mariutti suggests the true carbon emissions are closer to 170 grams to 250 grams of CO2 per kWh—between three to five times higher than reported by the U.N.

"For 10 years, the @IPCC-CH has been presenting misleading evidence on the carbon intensity of photovoltaic energy," Mr. Mariutti said in a Twitter post on July 24.

The IPCC didn't respond to a request for comment on the report based on independent calculations.

'Dirty Secret'

In April, Mr. Mariutti, an analyst specializing in economics as well as climate and energy policy, published a report titled "The Dirty Secret of the Solar Industry." In the report, he argued that the IPCC was vastly underestimating the amount of carbon generated by Chinese-made photovoltaic cells because it was basing its calculations on a Europe-based, low-carbon supply chain rather than the coal-reliant production processes in China.

"We are investing hundreds of billions of dollars a year in technologies that are low-carbon only because someone wrote it down somewhere," Mr. Mariutti said in the executive summary of his report. "There aren’t any national or international authorities who have bothered to understand on what basis and how this 'paper knowledge' was assembled."

The problem is that most of the carbon intensity data that the IPCC—and governments—rely on for solar panels are based on modeling that's likely to have vastly underestimated the carbon emissions of solar power because of a lack of transparency, or simply inaccurate or "made-up" data from Chinese manufacturers, according to the Environmental Progress report.

Over the years, China has become a dominant force in the production of solar panels. For example, about 97 percent of the global supply of solar wafers—a key component of photovoltaic cells—are made in China.

A masked worker in a lab coat sorts silicon wafers at the factory of solar cell maker Trina Solar in Changzhou, China, on Nov. 28, 2009. (PHILIPPE LOPEZ/AFP via Getty Images)

However, China's growing share of the solar panel market hasn't come about because of innovation.

"The majority of experts consulted by Environmental Progress agree that China’s competitive advantage did not lie in an innovative new technological process, but rather in the very same factors the country has always used to outcompete the West: cheap coal-fired energy, mass government subsidies for strategic industries, and human labor operating in poor working conditions," according to the group's report.

When he first released his independent report in April, Mr. Mariutti said in a post on Twitter that he was motivated to publish his findings "in light of the acceleration of European climate policy, which threatens to condemn Italy to irreversible decline."

He said he felt it was his duty to make his research public in order to inform public policy decisions.

"In the last 10 years, the IPCC has systematically underestimated the carbon intensity of photovoltaic energy by pretending that photovoltaic modules are produced in Europe rather than in China," he said at the time.

"By recalculating the carbon footprint of a photovoltaic system on the basis of a predominately coal-based energy mix, it is possible to estimate that the global average carbon intensity of photovoltaic energy is at least 200 [grams of CO2 per kWh]."

Mr. Shellenberger, for his part, has long warned about the holistic environmental impacts of the solar panel industry.

Solar Panel Waste Tsunami

This aerial view shows the Crescent Dunes Solar Energy Project located near Tonopah, 190 miles (310 kilometers) northwest of Las Vegas on July 30, 2020. (Daniel Slim/AFP via Getty Images)

In 2021, Mr. Shellenberger told NTD’s “The Nation Speaks” that the economics of solar panel production, deployment, and recycling shows that the technology has a “toxic” and “dangerous” dimension, while its advocacy is driven by ideological leanings rather than by sound science.

“We’ve been in a sort of hypnotic trance,” Mr. Shellenberger said at the time, referring to what he characterized as the misguided belief that solar power is an environmentally friendly alternative to traditional forms of power generation such as nuclear.

“It’s a spiritual pursuit,” he said. “There’s the idea that ... we’ll protect the natural environment by being dependent on natural energy flows like sunlight. It’s not a scientific view. It actually is worse for the environment.”

A Harvard Business Review study concluded that solar panels are being replaced faster than expected because of various economic incentives, and warned of a rising mountain of solar panel trash “of existentially damaging proportions” unless incentives are adopted to drive down the high costs of recycling.

The Harvard study cited estimates by Garvin Heath, senior scientist at the National Renewable Energy Laboratory, who told PV Magazine that it costs $20 to $30 to recycle a panel, versus $1 to $2 to send it to a landfill. Harvard Business Review concluded that the bright promise of more widespread adoption of solar energy as an environmentally friendly alternative “would darken quickly as the industry sinks under the weight of its own trash.”

Asked about the study, Mr. Shellenberger confirmed the high recycling costs but said that they’re just one part of the end-of-life burden of solar energy. The panels contain heavy metals such as lead, which can be released as a toxic cloud if the panels shatter during disposal.

"It's hazardous waste," he said at the time.

With the proliferation of renewable energy sources, especially solar power, in the United States, the issue of tackling waste has become a growing concern.

The United States currently has an estimated 149.5 gigawatts of solar capacity installed nationwide.

Research firm Wood Mackenzie expects the country's total installed solar capacity to hit 378 gigawatts by 2028.