A bipartisan group of U.S. senators is calling on the Biden administration to quickly review the Commerce Department's recently launched investigation into the alleged evasion of import tariffs by Chinese solar manufacturers and for the agency to issue a preliminary determination on the matter.

A May 1 letter signed by 22 senators flagged the potential for "massive price hikes" that could result if utilities pass on added costs to consumers, citing the possibility of retroactive tariffs of up to 250%.

Those signing the letter included 19 Democrats, Republicans Thom Tillis of North Carolina and Jerry Moran of Kansas, and independent Angus King of Maine.

"Initiation of this investigation is already causing massive disruption in the solar industry, and it will severely harm American solar businesses and workers and increase costs for American families as long as it continues," the letter to President Joe Biden stated. "We strongly urge your administration to swiftly review the case and make an expedited preliminary determination."

The Department of Commerce probe, requested by Silicon Valley-based solar panel manufacturer Auxin Solar Inc., centers on whether Chinese makers of crystalline silicon solar cells and modules have used factories in Cambodia, Malaysia, Thailand and Vietnam to circumvent existing tariffs on solar goods made in China.

The Solar Energy Industries Association, or SEIA, on April 27 warned that the investigation is disrupting U.S. access to solar panels and resulting in widespread project cancellations and delays, undermining the Biden administration's climate and renewable energy policies. More than 300 utility-scale projects, totaling 51 GW of solar capacity and 6 GWh of battery storage, have been canceled or delayed because of the probe, putting $52 billion of private investment at risk, according to SEIA.

"We strongly support developing a domestic solar manufacturing supply chain, but current demand for solar products far exceeds existing domestic production capacity," the senators said, pointing to the possible loss of more than 100,000 solar industry jobs.

First Solar Inc., the largest U.S.-headquartered solar manufacturer, supports the investigation and has blasted the solar lobby's "sky is falling" narrative. First Solar's use of cadmium-telluride thin-film technology instead of crystalline silicon has meant it is largely unaffected by recent solar tariffs.

'I have to follow the statute'

In California, where SEIA estimates nearly $8 billion in planned investments into large-scale solar projects are at risk, Gov. Gavin Newsom is concerned over potential negative impacts on the state's efforts to reliably decarbonize its grid.

"The inquiry, and resulting uncertainty, is delaying at least 4,350 MW of solar-plus-storage projects in total nameplate capacity that we need to come online between 2022 and 2024," Newsom said in an April 27 letter to Commerce Secretary Gina Raimondo.

"Delays and interruptions of this magnitude hinder our efforts to combat climate change and threaten our ability to maintain energy reliability ahead of the retirement of 6,000 MW primarily generated by aging, gas-powered once-through-cooling plants," Newsom said.

The governor urged Raimondo to take "immediate action to resolve this issue as soon as possible and restore certainty in the market."

U.S. Sen. Jacky Rosen, D-Nev., whose office released the letter to Biden, pressed Raimondo on making an expedited preliminary determination during a hearing before the Senate Committee on Commerce, Science and Transportation on April 27.

Raimondo declined to commit to fast-tracking a decision.

"What I will commit to you is moving as fast as possible, consistent with the statute, to conduct that investigation," Raimondo said. "I understand you need certainty but I have to follow the statute."

Despite mounting pressure to hasten the investigation, analysts at Roth Capital Partners LLC said in an April 29 note to clients that the Biden administration "has limited options to change the course of events," referring to comments from Raimondo.

U.S. Rep. Scott Peters, D-Calif., also aired concerns over the trade probe to Energy Secretary Jennifer Granholm during an April 28 hearing before the House Energy and Commerce Committee.

"I really think we have to look at how we shoot ourselves in the foot by allowing this kind of stuff to happen," Peters said.

Granholm said she shared the representative's concern over the impact of the solar tariff probe and the need to boost U.S. manufacturing.

"The bottom line is that we have to accelerate," Granholm said.

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