(Bloomberg) -- On top of an old coal mine in western Pennsylvania, developers were preparing to install the first of 237,000 new solar panels — a living embodiment of the transition away from fossil fuels into clean energy. Just as the Maple Hill solar farm was getting underway, things came to an abrupt halt.

The $30 billion U.S. solar industry is being ensared in a trade probe that’s leaving projects like Maple Hill in limbo and threatening to slow down — possibly even derail — the country’s shift to renewable power. The panels crucial to the solar farm in Portage, Pennsylvania, were being made in Thailand. But the threat of tariffs, equal to as much as 239% of the equipment’s value, forced the supplier to halt shipments. 

“Solar projects across the country, including ours, just got stopped in their tracks,” said Tom Rumsey, senior vice president of Competitive Power Ventures, the developer behind Maple Hill.

The fallout is rippling through the industry. NextEra Energy Inc. is warning a huge number of its projects could be delayed, while SOLV Energy is shelving five planned installations and laying off 500 workers. The Public Service Company of New Mexico said planned renewable projects may cost more and won't be operating until after next summer.

At least 65% of U.S. solar capacity set to come online in 2022 and 2023 is now at significant risk of cancellation or delay, according to an advocacy group fighting the trade probe.

And that’s just based on the announcement of the investigation, which could take a year to complete. 

If the Commerce Department decides to expand tariffs, the consequences would be even more far-reaching. The duties would hit Malaysia, Thailand, Vietnam and Cambodia — countries that supply the U.S. with 80% of its imported modules. While it’s possible that other nations could help fill some of the supply gap and new domestic manufacturing may eventually spring up, the turbulence could take years to settle. The upheaval would likely jeopardize President Joe Biden’s green ambitions, including his goal to decarbonize the electricity sector by 2035.

Why the Energy Transition Is Facing Setbacks

The probe represents just the latest setback for the nation’s energy transition. The solar industry is already confronting Biden administration policies that hamper shipments of key equipment, and legislation to expand critical tax credits is stalled in Congress. Meanwhile, wind power is under threat as turbine makers struggle to translate soaring demand into profit, U.S. coal use is surging and Biden is imploring oil companies to produce more crude.

“I believe that the president, at his core, is a climate and justice champion,” said Suzanne Leta, head of policy and strategy at rooftop company SunPower Corp. “But we're not quite seeing the urgency we need in order to meet that objective.”

Read more: Experts say Biden’s signature climate goal is all but dead

Solar generation was earmarked to potentially provide 40% of the nation’s power under Biden’s climate plans. Now, 83% of companies surveyed by the Solar Energy Industries Association say deliveries of panels have been delayed or canceled because of the trade probe. The group estimates that 318 projects totaling 51 gigawatts of solar capacity are being impacted. That’s equivalent to the electricity generated by more than 51 nuclear reactors.

Many analysts say it's too early to quantify what impact the possible duties would have on U.S. greenhouse gas emissions, though modeling provided by the solar association suggests an extra 364 million metric tons of carbon dioxide could be unleashed by 2035 — equivalent to the annual release from 97 coal plants.

“This is a lost opportunity,” said SOLV Chief Executive Officer George Hershman. 

The solar industry “is well positioned to meet the demand,” he said. “We have an administration that all of us in the industry supported. We wanted this administration with this agenda. And to think that we’re two years in, and we’re talking about laying off solar workers. These are really self-inflicted wounds.”

In Pennsylvania, Maple Hill was originally planned as a 127-megawatt solar farm. The company now has just 20 megawatts worth of panels on hand and little chance of nabbing more quickly.

“We literally have a project with a quarter of the panels installed or in storage — with the remaining panels in flux,” said Rumsey of Competitive Power Ventures. “It’s fully permitted. You’re paying for the land, your construction team is mobilized, you have your interconnect. All you’ve got to do is construct it.”

What the Commerce Department Is Weighing

The Commerce Department is evaluating whether companies are unfairly skirting 10-year-old duties on Chinese solar cells and modules by assembling the gear in Malaysia, Vietnam, Thailand and Cambodia.

If the agency ultimately concludes tariffs are being circumvented, it could extend antidumping and countervailing duties — such as 49.79% levied against China’s JinkoSolar Co. and 40.27% for Longi Green Energy Technology Co. — to the companies’ operations in Southeast Asia. A broad country-wide rate — now set at 238.95% for China — could apply to a handful of manufacturers that haven’t petitioned the U.S. for lower, company-targeted tariffs. That would include Zhongli Talesun Technologies (Thailand) Co., the supplier for Competitive Power Ventures. 

Talesun didn't respond to an email seeking comment.

Duties could be imposed on products shipped to the U.S. since the probe started in late March. But in an unusual twist, tariffs could be retroactively applied, potentially to shipments dating as far back as November 2021.

That would further pressure an industry with notoriously slim margins — typically in the range of 5% to 8%, according to consultancy Wood Mackenzie.

Spending on panels generally represents about a third of the cost of a utility-scale solar project, and current supply disruptions translate to roughly $5.6 billion of capital expenditures in 2022, according to Pol Lezcano, a solar analyst BloombergNEF.

The U.S. added 17.8 gigawatts of utility-scale solar capacity in 2021, but BNEF projects deployment will fall to 16.8 gigawatts this year amid supply-chain snags and the trade probe.

“Developers and module makers are trying to work out who pays for the tariff, but without knowing how much they will have to pay, discussions cannot move forward,” said BNEF analyst Tara Narayanan.

‘It’s Been Panic’

To be sure, U.S. solar companies have a long history of issuing dire predictions about threats to the industry, only to beat the odds. Before former President Donald Trump slapped tariffs as high as 30% on panels and cells in 2018, solar companies howled about lost jobs and decimated projects, but utility-scale installers were able to blunt the pain by using two-sided models that dodged the duties.

This time, the threat is more serious, said Mike Kruger, president of the Colorado Solar and Storage Association.

“It’s been panic in a way that I haven’t seen before,” said Kruger, a veteran of the Commerce Department.

Supporters of U.S. solar manufacturing who back the trade investigation say the U.S. can’t afford to wait any longer to counter China’s solar manufacturing dominance. 

Read More: How China beat the U.S. to become the world’s solar champion

At one point there were 75 major solar-parts factories in the U.S., a number that was expected to grow as the industry flourished. Instead, most plants have now been shuttered.

“For years, Chinese solar producers have refused to fairly price their products in the U.S. and have gone to significant lengths to continue undercutting American manufacturers and workers,” said Mamun Rashid, CEO of San Jose, California-based Auxin Solar, the American manufacturer that persuaded the Commerce Department to open the trade probe.

The U.S. must enforce its trade laws to rebuild the American solar supply chain and combat “pervasive backdoor dumping,” Rashid said. 

Jeff Ferry, chief economist of the pro-manufacturing Coalition for a Prosperous America, says the decision by foreign panel makers to halt exports to the U.S. is “a cold-blooded game of chicken with the Biden administration.”

“They are gambling that by stopping exports into the U.S. for several months they will create such fear among the climate advocates in the administration that the administration will cave in and abandon” the trade probe, he wrote in a blog post. 

While Biden has successfully neutered the impact of other solar tariffs, the inquiry underway now is apolitical by design, following parameters built into a 92-year-old U.S. trade law. That’s one reason White House officials who champion renewable energy have steadfastly refused to get involved. 

Ali Zaidi, the deputy White House national climate advisor, told attendees of the BNEF Summit last week that it’s a “quasi-judicial process,” meant to be “independent.”

Stuck Waiting

Nestled into the mountains of Western Pennsylvania, the Maple Hill solar farm sits on cleared timber land, with a former coal mine deep underground. The Competitive Power Ventures’ project is now a field of mostly barren racks, driven into the ground to support the two-sided solar modules that, for the most part, haven't arrived.

When news of the trade probe broke and shipments stopped, “we scrambled,” said Sean Finnerty, executive vice president of renewable energy at Competitive Power Ventures. “We called every supplier that we have relationships with,” he said.

Some panels are being sold at a premium from now-delayed projects. But that doesn’t mean they will work at Maple Hill. They may be the wrong voltage and size for the custom racks at the site. Panels the company has ordered from other countries for future projects also aren’t compatible.

“Even if you can find panels, it’s not like plugging in a Duracell battery instead of an Eveready,” Finnerty said.

A key consideration in the trade probe is whether the Commerce Department determines the final assembly of solar cells and modules in Southeast Asia — using Chinese parts — is “minor or insignificant,” a threshold for finding if circumvention has occurred. The agency has until Aug. 29 to issue preliminary findings, with the extended deadline for a final determination in April 2023.

If Commerce issues an initial finding that circumvention hasn’t occurred, it could go a long way to restarting deliveries even before a final decision. The agency has never before overturned such a negative initial ruling.

In the meantime, solar-farm developers have little recourse.

“It’s going to be a bloodbath out there,” said Abigail Ross Hopper, the president of the Solar Energy Industries Association.

It's a far cry from the optimistic growth trajectory the solar industry had anticipated just last year, Hopper said. Now, some companies are predicting fewer solar installations this year than last — even fewer than under the Trump administration, she said. 

“We’re going backwards.”

©2022 Bloomberg L.P.