Blykalla broke ground on a non-nuclear advanced reactor testing site at the Oskarshamn nuclear power plant in February 2025 — validating key components and safety systems of the SEALER lead-cooled fast reactor. The Oskarshamn site provides access to nuclear-grade infrastructure, an experienced nuclear workforce, and regulatory familiarity. Blykalla is also carrying out engineering with industrial partners including Uniper, KSB, and ABB. The testing programme is a prerequisite for securing a construction site and licence for the first SEALER deployment in Sweden. The Swedish Energy Agency awarded a SEK 99 million grant for the pilot facility near Oskarshamn, which tests the proof of concept of the SEALER technology (also referred to as the SEALER-E prototype); the first phase of construction was expected to be completed by June 2025 with tests starting in the third quarter of 2025.