The Federal Communications Commission has banned internationally manufactured power inverters, including those used in solar PV and energy storage projects, from being imported into the United States.

Yesterday, the FCC added “foreign-produced power inverters” to a list of communications products and services it considers a risk to national security, citing alleged supply-chain and cybersecurity risks to electrical infrastructure.

“These vulnerabilities could enable foreign firms to turn off the inverters or use them to collect and exfiltrate data, facilitate remote access and surveillance by foreign government actors, or be otherwise exploited through a cyberattack,” the public notice filing states.

Only international inverters conditionally approved by the FCC can be imported into the United States, and receiving that designation requires submitting an application to the FCC.

“I welcome these executive branch national security determinations, and I am pleased that the FCC has now added foreign produced advanced robotics and power inverters to the FCC’s Covered List,” said Brendan Carr, FCC chairman, in a press release. “Following President Trump’s leadership, the FCC will continue to do our part to secure America’s critical supply chains, and, with today’s action, the FCC is acting in lock step with our national security agencies to do just that.”

An “Executive Branch interagency body,” whose membership was not disclosed, directed the FCC to ban foreign inverters. The agency says inverters that have already been purchased, approved by the FCC, or already in operation are not affected by the ban. New models of power inverters will only be eligible for import if approved by the FCC, while older models can still be imported.

The ban is effective immediately, but questions remain about how it will affect interconnection for solar and energy storage projects and inverter procurement going forward. Because inverters are a core component that convert solar-generated direct current into grid-compatible alternating current, any import restriction can add a compliance step for manufacturers and project developers that rely on imported equipment. The announcement comes six months after a Department of Energy investigation found that a sampling of Chinese-manufactured inverters did not contain malicious software.

This is a developing story. Solar Power World said it has reached out to solar inverter manufacturers and industry members for further comment.