Poland’s Synthos Green Energy (SGE) and Bulgarian firm Blue Bird Energy (BBE) have signed a letter of intent (LOI) to partner on the deployment of small modular reactors (SMRs) in Bulgaria. The two companies plan to establish a joint venture aimed at building a fleet of up to six BWRX-300 SMRs in Bulgaria.
The 300 MWe BWRX-300, designed by US company GE Vernova Hitachi (GVH), is a 10th generation water-cooled, natural circulation SMR with passive safety systems that leverages the design and licensing basis of GVH’s 1,500 MWe ESBWR boiling water reactor and its experience with cross-border regulatory collaboration.
BBE’s key shareholders are Bulgaria’s biggest construction and engineering group Glavbolgarstroy (GBS), founded in 1969, and Bulgaria’s leading copper mining and processing company, Asarel-Medet JSC.
SGE was established in 2019 by Polish tycoon Michał Sołowow, owner of the biggest privately held industry group in Poland, MS Galleon. Currently, SGE, a co-investor in the standard design for the BWRX-300, is establishing partnerships and projects in a number of European countries. Their flagship project is in Poland in cooperation energy company ORLEN, where ORLEN Synthos Green Energy (OSGE) – a joint venture between Polish chemical producers SGE and PKN Orlen – plans to deploy a fleet of 24 BWRX-300 reactors. Work is underway at three sites with the aim of completing the first unit by 2032.
The new SGE-BBE joint venture will work in Bulgaria to:
- Select and prepare deployment sites.
- Facilitate site and design licensing.
- Manage construction and project development.
- Coordinate project funding.
- Ensure safe, reliable, and efficient commercial operation.
SGE CEO Rafał Kasprow said: “Partnering with Blue Bird Energy will strengthen our European SMR development platform and help us deliver affordable energy that meets the needs of the Bulgarian people. With today’s announcement, Bulgaria joins the US, Canada, Poland, Hungary, and others who are in the process of deploying this world leading US technology. We are confident that the Bulgarian economy will benefit from low-cost, reliable, baseload energy. Additionally, Bulgarian companies will play a significant role in the global BWRX-300 supply chain.”
Kalin Peshov, BBE Board Chairman noted: “We are excited to partner with energy frontrunners such as GE Vernova Hitachi (GVH) and SGE. The 65 years of nuclear experience of GVH and the proven track record of SGE bringing the BWRX-300 technology to Europe would be invaluable in supporting our mission to provide Bulgaria with secured long-term energy supply.
SMR technology, its rapid development worldwide, and the opportunities for quick implementation of a similar project in Bulgaria were discussed recently in Sofia by Energy Minister Zhecho Stankov. The working meeting held at the Ministry of Energy on the development of high value-added energy technologies for the Bulgarian economy was attended by representatives of GE Vernova / GE Hitachi Nuclear Energy (USA), Glavbolgarstroy/Blue Bird Energy (Bulgaria), Synthos Green Energy (Poland) and representatives of the US Embassy and the Bulgarian Energy Holding.
The talks focused on technological solutions offered by the BWRX-300. These plants are being offered as a modern, smaller-scale technology for implementation in Bulgaria and are intended to complement and synergise with the current project to build two Westinghouse AP1000 reactors at the Kozloduy NPP.
While SGE plans to expand its SMR business based on the BWRX-300 to Central and Eastern Europe, including the Czech Republic, Hungary, Lithuania, Bulgaria and Romania, GVH is developing projects in Canada and the US.
GVH’s first BWRX-300 is under construction at Ontario Power Generation’s Darlington site in Canada, with completion expected by the end of the decade. Four grid-scale commercial BWRX-300 units are planned for the site. Ontario Power Generation selected the technology in 2021.
In December 2025, the US Department of Energy (DOE) awarded Tennessee Valley Authority (TVA) $400m to advance deployment of a BWRX-300 SMR at the Clinch River Nuclear site in Tennessee, as well as accelerate the deployment of additional units with Indiana Michigan Power and Elementl. In May, TVA had submitted a construction permit application to the Nuclear Regulatory Commission (NRC) to build the first BWRX-300 at Clinch River,
Earlier in 2025, Canadian construction and infrastructure development company Aecon Group signed a teaming agreement with Estonia’s Fermi Energia to advance cooperation on the development and deployment of BWRX-300 technology in Estonia. Also, the BWRX-300 is one of two SMR designs selected by Sweden’s Vattenfall for new nuclear capacity at the Ringhals NPP on the Värö Peninsula.
