Polish billionaire Michal Solowow and the Solorz family have agreed to jointly build small modular reactors, marking their second attempt to cooperate on a nuclear project as Poland overhauls its aging power sources. Solowow’s company SGE SA signed a deal with ZE PAK SA aimed at working out the details of their future cooperation to build and operate small modular reactors, according to a regulatory filing. Solowow, who has exclusive rights to offer GE Vernova Hitachi’s BWRX-300 reactors, will hold a majority stake in the new joint venture.

Poland is heavily investing in upgrading its power system, adding renewable energy and gas-fired units to replace coal plants, which currently account for more than half of its electricity generation. Apart from small nuclear reactors, the country is planning to build its first large nuclear power station in 2036.

“SGE and ZE PAK are addressing one of the greatest challenges facing the Polish energy sector: the need to replace aging coal-fired power plants while simultaneously meeting growing demand for electricity,” they said in a separate statement. The partners estimate that the nation’s shortfall in “stable” generation capacity could reach 5 gigawatts in 2032. To help close that gap, they plan to construct six reactors with a total capacity of 1.8 gigawatts at the site of PAK’s lignite-fired power facility in central Poland. PAK’s land, valued at 300 million zloty ($77 million), is part of the deal. The companies didn’t provide a timetable for construction or the start of power generation.

The agreement comes on top of SGE’s project to build as many as 26 reactors with Orlen SA. As talks with the state-controlled energy giant on a final deal drag on, SGE has started to look for additional opportunities. In its latest financing round, SGE attracted prominent Polish entrepreneurs, including InPost SA founder Rafal Brzoska and ElevenLabs Inc. co-founder Mati Staniszewski. The company is also eyeing a stock exchange debut in 2028.

Solowow has a portfolio spanning chemicals and energy to ceramic tiles in several European countries, including the Netherlands and France. The billionaire has long called for Poland to speed up SMR investments in a bid to help the country cut high energy bills.

For the Solorz family, the deal offers a potential replacement for its aging and costly lignite assets. It also follows a settlement last month that ended a long-running dispute between Zygmunt Solorz and his children over control of the family’s media, telecommunications and energy empire.

Tuesday’s agreement marks the second attempt by the two wealthy Poles to jointly pursue nuclear ambitions. Earlier this decade, Zygmunt Solorz initially agreed with Solowow to build small modular reactors. He later abandoned the project and sealed a deal with Korea Hydro & Nuclear Power on large reactors, before Solorz’s company sold its stake last year.

“The energy and fuel crises of recent years clearly demonstrate that Poland must have its own stable energy sources,” Piotr Zak, one of Zygmunt’s two sons, said in the statement.