Company’s South Wales Project Advances Towards 2027 Licensing Target
Last Energy, a US-based micro-nuclear technology developer, announced today that its power plant design, the PWR-20, has successfully completed a Preliminary Design Review (PDR), becoming the first nuclear developer to do so in the United Kingdom. The review was conducted by the UK’s nuclear regulators: the Office for Nuclear Regulation (ONR), the Environment Agency, and Natural Resources Wales (NRW).
The regulators’ joint summary report, which confirms successful completion of the review in June 2025, marks a significant development in Last Energy’s efforts to deploy the first commercial microreactor in the UK. Completion of the process follows over a year of Early Engagement with the regulators and five months of PDR-specific review, which included design workshops and technical submissions across selected topic areas.
“As the first micronuclear developer to complete a Preliminary Design Review, we applaud the UK’s nuclear regulators for establishing a clear, flexible and direct regulatory pathway for micro-nuclear technologies to engage in nuclear licensing and environmental permitting,” said Michael Jenner, CEO of Last Energy UK. “Unlocking nuclear power at scale is essential to decarbonising the industrial economy and driving economic growth across the UK. Completing our PDR has provided essential guidance to efficiently undertake and complete licensing processes, positioning Last Energy to deliver the UK’s first commercial microreactor.”
Today’s announcement marks a major regulatory step forward for Last Energy’s South Wales project and confirms that a pathway exists to complete nuclear site licensing by 2027. According to the regulators’ summary report, Last Energy’s target to receive a site licence decision by December 2027 is achievable — contingent on the company delivering its submissions to the standard and schedule agreed in the PDR. The PDR process covered three topic areas: organisational plans and arrangements, environment and decommissioning, and safety analysis process and maturity, and included review of Last Energy’s fully-passive, walk-away-safe design approach.
In January 2025, Last Energy became the first microreactor developer to formally enter nuclear site licensing for its plans to develop four 20 MWe microreactors in South Wales. Completion of the PDR now equips Last Energy with tailored regulatory guidance as it moves into the next phase of regulatory assessment of Last Energy’s design, safety, security, and environmental cases.
In October 2024, Last Energy announced plans to deploy four microreactors in South Wales at a vacant site that housed the coal-fired Llynfi Power Station. The company obtained site control that month, followed by a US Export-Import Bank LOI for $103.7 million (USD) to support the financing for the first installation, pending final commitment. In January 2025, Last Energy accepted a grid connection offer from National Grid Electricity Distribution (NGED) for 22 MW of export capacity.
About Last Energy: Founded in 2019, Last Energy is a micro-nuclear technology developer on a mission to unlock energy access by transforming nuclear plants from complex construction projects into a mass-manufacturable product. Last Energy’s PWR-20 produces 20 MWe, is fully modular, and designed for flexible siting, plug-and-play installation, and rapid scalability. By productising nuclear energy, Last Energy is transforming power generation for data centres, manufacturers, and other industrial customers throughout the United Kingdom, United States, and Europe.
