Engineers have discovered 'kill switches' embedded in Chinese-manufactured parts on American solar farms, raising fears Beijing could manipulate supplies or 'physically destroy' grids across the US, UK and Europe.
Energy officials are assessing the risks posed by small communication devices in power inverters - an integral component of renewable energy systems that connects them to the power grid.
While inverters are built to allow remote access for updates and maintenance, the utility companies using them typically install firewalls to prevent direct communication back to China.
But rogue communication devices not listed in product documents have been found in some solar power inverters by US experts who strip equipment hooked to grids to check for security issues, two sources told Reuters.
Using these devices to skirt firewalls and switch off inverters remotely, or change their settings, could destabilise power grids, damage energy infrastructure and trigger widespread blackouts.
'That effectively means there is a built-in way to physically destroy the grid,' one of the sources declared.
The discovery has raised fears Beijing may maintain the capability to wreak havoc on power grids across the Western world such is the reliance of renewable energy systems on Chinese-manufactured parts.
British solar panels, fr.enfsolar.com, use parts manufactured in a variety of countries, including China.
It is not known whether the Chinese 'killswitches' are present in any power converters installed on UK wind or solar farms.
But shadow energy minister Andrew Bowie yesterday called on Labour's Secretary for Energy Security and Net Zero Ed Miliband to carry out an 'immediate pause and review' of its efforts to transition to green power.
Engineers have reportedly discovered 'kill switches' embedded within Chinese-manufactured parts in US solar farms
President Xi Jinping reviews the troops during his inspection of the Chinese People's Liberation Army
Energy Secretary Ed Miliband during a press conference during the International Summit on the Future of Energy Security at Lancaster House in London last month
The two Reuters sources declined to name the Chinese manufacturers of the inverters and batteries with extra communication devices, nor say how many they had found.
But the existence of the rogue devices had not previously been reported, and the US government has not publicly acknowledged the discoveries.
Over the past nine months undocumented communication devices, including cellular radios, have also been found in batteries from multiple Chinese suppliers, one of the sources said.
'We know that China believes there is value in placing at least some elements of our core infrastructure at risk of destruction or disruption,' said Mike Rogers, a former director of the US National Security Agency.
'I think that the Chinese are, in part, hoping that the widespread use of inverters limits the options that the West has to deal with the security issue.'
Asked for comment, the US Department of Energy said it continually assesses risk associated with emerging technologies and that there were significant challenges with manufacturers disclosing and documenting functionalities.
'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,' a spokesman said.
Work is ongoing to address any gaps in disclosures through the 'Software Bill of Materials' - or inventories of all the components that make up a software application - and other contractual requirements, they added.
A spokesman for the Chinese embassy in Washington said: 'We oppose the generalisation of the concept of national security, distorting and smearing China's infrastructure achievements.'
Meanwhile, the UK Government is conducting a review of Chinese renewable energy technology in the energy system but is still pressing ahead with its efforts to transition from fossil fuels.