A team of engineers in the U.S. took apart a solar power inverter. It looked like any other—sleek, compact, humming with the promise of sustainability. But buried deep inside, they found something that wasn’t supposed to be there.
It wasn’t in the manual. It wasn’t listed in any documentation. But here it was: a communication device, capable of talking to the outside world. Capable, potentially, of talking back to China.
This discovery—and others like it—has set off alarms across U.S. energy and security circles. For months, experts examining renewable energy equipment imported from China have been quietly finding rogue components in solar inverters and large batteries, two people familiar with the investigations told Reuters. These undocumented communication modules offer an invisible back door into devices that regulate a growing share of the world’s electricity.
“It effectively means there is a built-in way to physically destroy the grid,” said one of the experts, speaking on condition of anonymity.
Renewable Risk
Power inverters convert the direct current produced by solar panels and wind turbines into the alternating current used by the grid. They’re also embedded in home batteries, electric vehicle chargers, and even heat pumps.
Because they often require remote updates and maintenance, inverters are designed to be connected to the web. But to prevent tampering or intrusion, utility companies typically build digital walls around them. The rogue devices recently discovered threaten to undermine those protections—creating new pathways into the heart of the grid.
While the U.S. Department of Energy (DOE) has not publicly acknowledged the finds, it confirmed to Reuters that it is “continually assessing risk associated with emerging technologies.” A spokesperson added that “while this functionality may not have malicious intent, it is critical for those procuring to have a full understanding of the capabilities of the products received.”
The discoveries remain under wraps. Sources declined to name the Chinese manufacturers involved or to reveal how many devices have been compromised. But the implications, experts say, are vast.
Mike Rogers, a former director of the U.S. National Security Agency, put it bluntly: “We know that China believes there is value in placing at least some elements of our core infrastructure at risk of destruction or disruption.”
Geopolitics Through the Grid
The revelations arrive at a tense geopolitical moment. As relations between China and the West sour, energy security is becoming entangled in national defense. In February, U.S. lawmakers proposed a bill—the Decoupling from Foreign Adversarial Battery Dependence Act—banning the Department of Homeland Security from purchasing Chinese-made batteries starting in 2027. Among the six companies targeted: CATL, BYD, Envision Energy, and Gotion High-tech.
Utilities are already bracing for a broader crackdown. Some, like Florida Power & Light Company, are reportedly reducing their reliance on Chinese inverters, although the utility declined to comment.
“Ten years ago, if you switched off the Chinese inverters, it would not have caused a dramatic thing to happen to European grids,” said Philipp Schroeder, CEO of German solar developer 1Komma5. “But now the critical mass is much larger.”
By some estimates, more than 200 gigawatts of solar capacity in Europe is linked to Chinese-made inverters. That level of dependence has become a growing concern among European intelligence agencies. In November, Lithuania enacted laws banning remote Chinese access to large-scale renewable installations. Estonia’s intelligence chief warned of potential “blackmail” if similar steps aren’t taken. Britain is also reviewing the role of Chinese tech in its energy grid, with a decision expected in the coming months.
A Silent Disruption
In November 2024, those fears became reality.
Solar inverters in the U.S. and other countries were mysteriously disabled—from China. The incident, reported by three sources, revealed just how easily a foreign actor could reach across borders and influence local power supplies. Reuters could not verify the scale of the disruption. The DOE declined to comment.
The shutdown sparked a quiet dispute between U.S.-based inverter maker Sol-Ark and Chinese manufacturer Deye. Sol-Ark claimed no control over the inverters involved, which were not branded under its name. Deye did not respond to requests for comment.
The episode left grid operators scrambling—and underscored how little regulatory oversight exists for the devices now saturating rooftops and substations.
Uri Sadot, director of cybersecurity at Israeli inverter company SolarEdge, warned that even modest interference could trigger widespread outages. “If you remotely control a large enough number of home solar inverters, and do something nefarious at once,” he said, “that could have catastrophic implications to the grid for a prolonged period of time.”
The threat, experts say, doesn’t require cutting-edge espionage. Many home installations remain below the size thresholds that trigger strict security reviews. Yet when aggregated, these small systems now feed significant power into national grids—enough to cause real damage if hijacked or shut down en masse.
NATO has taken notice. In a statement to Reuters, a spokesperson warned that China’s attempts to control infrastructure in member countries are “intensifying.” The alliance is urging countries to “identify strategic dependencies and take steps to reduce them.”
A Fragile Future
The energy sector is playing catch. Telecom and semiconductor industries already have regulations in place to curb Chinese influence. But the grid—arguably more vital—is still exposed.
The U.S. DOE says it’s working to strengthen domestic manufacturing and require full disclosure of hardware and software components, including so-called “Software Bills of Materials.” These inventories could help detect foreign communication modules before they reach American homes.
But enforcement remains difficult. And in the meantime, Chinese companies continue to dominate a global market rushing to meet climate goals. “China’s dominance is becoming a bigger issue because of the growing renewables capacity on Western grids and the increased likelihood of a prolonged and serious confrontation,” said Schroeder.
The paradox is stark. The same devices powering a green future may be wired to shut it down.
And in an age when energy independence is once again a national imperative, the grid may no longer be just an engineering challenge—but a front line.
