US-based Last Energy has secured power purchase agreements (PPAs) for 34 PWR-20 small modular reactor (SMR) units with four industrial partners in the UK and Poland. Last Energy said the deals, worth $18.9bn in power sales, mark “the largest pipeline of new nuclear power plants under development in the world”.

Last revealed its completed PWR-20 design in 2022. The PWR-20 is a 20 MWe (60 MWt) single-loop pressurised water reactor (PWR) that has a 300C continuous output based on accepted PWR technology. The design uses standard full-length PWR fuel enriched to 4.95% and closed-cycle air cooling. Power plant modules would be built off-site and assembled in modules. By using ready-made modular components, Last says a reactor could be assembled within 24 months of the final investment decision. The assumed lifetime of the power plant is 42 years.

Last says that, because the technology uses a standardised balance of plant configuration and modular construction, a plant could be fully factory fabricated and installed on-site “in as little as three months”. This “simplifies the regulatory process, keeps project costs below $100m, and unlocks both private financing and customer validation”, the company notes. “We cover all aspects of the investment process, including design, construction, financing, service, and operation.”

PPAs for 10 20 MWe plants were signed with Katowice Special Economic Zone (KSSE) in southwestern Poland. KSSE, established in 1997 hosts 540 companies. Last says the agreement represents over $4.3bn in electricity sales over the lifetime of the contract and $1bn in inward energy and infrastructure investment in the zone. The first plant at KSSE could be commissioned in 2026.

KSSE Management Board President Janusz Michałek says industrial investors are looking for a secure carbon-free power supply, which they could seamlessly scale as their power requirements increase. “This project would provide the type of security and certainty in energy supply and price that our industrial partners need to make long-term investments in our area."

Last Energy also announced PPAs for 24 SMRs in the UK as part of three industrial partnerships, although the details were not disclosed. However, Last says they “represent a diversity of UK industries, including a life sciences campus, sustainable fuels manufacturer, and a developer of hyperscale data centres”. More information is expected “over the coming months, as project teams on both sides finalise arrangements for site selection and engagement with appropriate stakeholders”. Last believes that the first UK plant could also be commissioned in the 2026 timeframe. In total, these PPAs represent over $14bn in electricity sales, with total inward investment expected to be $2.4bn.

"The demand for zero-carbon, baseload energy solutions is huge, and micro nuclear is an ideal solution for distributed energy users," said Last Energy UK CEO Mike Reynolds. "Our private-sector led approach to delivering new nuclear power supports the wider government efforts to promote growth and investment in the green industries of the future."

Last Energy is a spin-off of the Washington-based Energy Impact Center, a research institute focused on near-term climate solutions founded in 2017, by leading Silicon Valley technologists. This is reflected in its elaborate website.

In July last year, Last Energy signed a Letter of Intent with the Legnica Special Economic Zone (LSEZ) – also in south-western Poland – and DB Energy on the construction of a power plant consisting of ten SMRs with a combined capacity of 200 MWe. The agreement also included a PPA of at least 24 years with LSEZ and its tenants.

However, the 2026 date for plant operation in Poland and the UK may prove optimistic as the plant designs will need to obtain the necessary licences. Last says it is “very engaged” with relevant regulatory bodies in target markets, and plant fabrication will depend on the outcome of this process.

Image: Artist's impression of Last Energy's PWR-20 small modular reactor unit (courtesy of Last Energy)