U.S. equities in solar-related names rallied on Monday after media reports said the Trump administration is preparing a draft rule that could bar imports of certain foreign-made inverters on national security grounds. Market moves led by Enphase Energy pushed its shares up 17.5% on the day, with SolarEdge Technologies rising 11% and Sunrun climbing 7%.
According to the reports, the U.S. Federal Communications Commission is working on a rule that would target new foreign models of inverters - devices that convert and manage power flows between solar installations, battery systems and the grid. The draft measure is said to concern the potential for these devices to be used to disrupt electricity supplies, and could be published as early as this year, the reporting added.
Sources behind the reporting said the administration revived the effort in part after a decision by the European Commission earlier in May to bar Chinese-made inverters from projects funded by public money. Those same sources cautioned that the U.S. proposal remains subject to change and could be altered or abandoned before any formal publication.
Both the Federal Communications Commission and the White House declined to comment on the draft rule, the reports said. The Chinese Embassy in Washington is quoted as opposing what it called an overstretching of the national security concept and an unjustified suppression of Chinese companies.
The reporting notes that China is the largest global manufacturer of inverters, led by firms such as Sungrow Power Supply and Huawei. Chinese producers have increased their presence in Western markets in part by offering lower prices, according to the accounts relayed in the reports.
Investors bid up shares of Enphase, SolarEdge and Sunrun as market participants reassessed the competitive landscape for inverter supply to U.S. projects. The prospect of a regulation that would limit new foreign models has implications for suppliers, project developers and the broader battery and solar equipment supply chains.
For now, uncertainty remains. The reported draft has not been published, officials declined to comment, and sources emphasised that the proposal could still be modified or shelved. Market reactions reflected the immediate reassessment of potential trade and procurement dynamics rather than any finalized policy.