Sweden's Blykalla Advances Lead-Cooled SMR Plan for 8 Reactors

A Swedish Bet on Lead-Cooled Reactors

Swedish nuclear startup Blykalla has filed an application to build a cluster of up to eight small modular reactors at Untra, in Tierp municipality, with the proposed park representing roughly 440 megawatts of generating capacity 1. The design relies on molten lead as a coolant rather than the pressurized water used in conventional plants, a choice that proponents argue allows reactors to run at higher temperatures with lower pressure, reducing certain safety risks and enabling more compact plant designs 1. If approved, the Untra project would mark one of the most ambitious lead-cooled SMR deployments proposed anywhere, and it arrives as governments and private developers worldwide race to commercialize small modular reactor technology.

Part of a Global SMR Push

Sweden's move is one thread in a much broader international push toward small modular reactors, driven partly by surging electricity demand from data centers and artificial intelligence workloads. In the United States, Oyster Creek in New Jersey has expressed interest in building an SMR-160 reactor, a plan that has already drawn concern from local environmentalists 3. On the coasts, the Port of Long Beach has signed an agreement to develop small offshore nuclear reactors intended to power port operations and vessels 6, while in Norway, energy and nuclear developers have partnered to test floating nuclear plants built around small modular reactor technology 7. Together, these projects illustrate how SMR ambitions are expanding well beyond traditional inland siting, into ports, coastlines, and offshore platforms.

Commercial Reality Check

Despite the flurry of announcements, the industry's commercial footing remains shaky. A Washington Examiner analysis notes that America's nuclear renaissance hinges not just on clever reactor designs but on the harder work of licensing, manufacturing at scale, securing financing, and actually deploying units — challenges that have tripped up earlier nuclear ventures 2. That skepticism has shown up sharply in financial markets: Financial Times reporting found that short sellers have collectively reaped more than $2 billion betting against SMR companies including NuScale Power, Nano Nuclear Energy, and Oklo over the past year 45. Even though these firms attracted significant investment from power-hungry AI hyperscalers eager to lock in future electricity supply, the FT notes the underlying technology remains unproven and has yet to generate consistent revenue 5.

Why It Matters

The juxtaposition is telling: while governments in Sweden, Norway, and the U.S. continue advancing SMR projects to meet future power needs — particularly from data centers — investors are simultaneously betting that many of today's SMR companies will stumble before delivering. Blykalla's lead-cooled design offers a genuinely novel technical approach, but its fate, like that of its peers, will ultimately depend on whether SMR developers can translate ambitious announcements into regulatory approval, financing, and operating reactors.