The BWRX-300 is a design for a
small modular nuclear reactor proposed by
GE Hitachi Nuclear Energy
GE Hitachi Nuclear Energy (GEH) is a provider of advanced reactors and nuclear services. It is headquartered in Wilmington, North Carolina, United States. Established in June 2007, GEH is a nuclear alliance created by General Electric and Hitach ...
(GEH). The BWRX-300 would feature
passive safety, in that neither external power nor operator action would be required to maintain a safe state, even in extreme circumstances.
Technology
The BWRX-300 is a smaller evolution of an earlier GE Hitachi reactor design, the
Economic Simplified Boiling Water Reactor
The Economic Simplified Boiling Water Reactor (ESBWR) is a passively safe generation III reactor, generation III+ reactor design derived from its predecessor, the Simplified Boiling Water Reactor (SBWR) and from the Advanced Boiling Water Reactor ...
(ESBWR) design and utilizing components of the operational
Advanced boiling water reactor (ABWR) reactor.
are nuclear technology that use ordinary
light water as a
nuclear reactor coolant
A nuclear reactor coolant is a coolant in a nuclear reactor used to remove heat from the nuclear reactor core and transfer it to electrical generators and the environment.
Frequently, a chain of two coolant loops are used because the primary co ...
. Like most boiling water reactors, the BWRX-300 will use a medium pressure steam-water cycle to remove heat from the core. A distinct feature of this reactor design is that the water is circulated within the core by
natural circulation
Convection is single or multiphase fluid flow that occurs spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convect ...
. This is in contrast to most nuclear reactors which require electrical pumps to provide
active cooling
Active cooling is a heat-reducing mechanism that is typically implemented in electronic devices and indoor buildings to ensure proper heat transfer and circulation from within.
Unlike its counterpart passive cooling, active cooling is entirely d ...
of the fuel. This system has advantages in terms of both simplicity and economics.
Decay heat removal
Immediately after a nuclear reactor shuts down, almost 7% of its previous operating power continues to be generated, from the decay of short-half-life
fission products
Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons, the releas ...
. In conventional reactors, removing this
decay heat
Decay heat is the heat released as a result of radioactive decay. This heat is produced as an effect of radiation on materials: the energy of the alpha particle, alpha, Beta particle, beta or gamma radiation is converted into the thermal movement ...
passively is challenging because those reactors are not designed to use natural circulation as the principal mechanism for cooling the core. The BWRX-300 reactor would be cooled by the
natural circulation
Convection is single or multiphase fluid flow that occurs spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convect ...
of water, making it distinct from most nuclear plants which require active cooling with electrical pumps.
New build proposals
In 2019, GEH expected construction to start in 2024/2025 in the US or Canada, entering commercial operation in 2027/2028, and for the first unit to cost less than $1 billion to build.
[
]
Canada
On December 1, 2021 Ontario Power Generation
Ontario Power Generation Inc. (OPG) is a Crown corporations of Canada, Crown corporation and "government business enterprise" that is responsible for approximately half of the electricity generation in the province of Ontario, Canada. It is w ...
(OPG) selected the BWRX-300 SMR for use at the Darlington Nuclear Generating Station
Darlington Nuclear Generating Station is a Canadian nuclear power station located on the north shore of Lake Ontario in Bowmanville, Ontario. It is a large nuclear facility comprising four CANDU reactor, CANDU nuclear reactors with a total outpu ...
. In October 2022, OPG applied for a construction license for the reactor, with plans to start operations in 2028.
On July 7, 2023 Ontario Power Generation chose three additional BWRX-300 SMR for construction at the Darlington New Nuclear Project in Ontario, Canada, joining the first already planned.
The final investment decision in May 2025 to proceed with the build of a BWRX-300 was based on a forecast cost of Canadian $7.7 billion (US$5.6 billion), with an estimated cost of Canadian $13.2 billion (US$9.6 billion) for the three further units on the same site; these costs include finance charges and some contingency.
Poland
On December 16, 2021 Synthos Green Energy (SGE), GE Hitachi Nuclear Energy and BWXT Canada announced their intention to deploy at least 10 BWRX-300 reactors in Poland in the early 2030s. On July 8, 2022 Orlen Synthos Green - a joint venture between SGE and PKN Orlen - applied to the National Atomic Energy Agency for a general opinion on the BWRX-300 SMR technology. In August same year a date of delivery of the reactor was announced: 2029. Construction of the reactor will begin in 2024, in Darlington, Ontario. In December 2023 the initial government permit was issued to Synthos Green.
USA
On August 3, 2022 TVA announced that it had entered into an agreement with GEH to support its planning and preliminary licensing for the potential deployment of a BWRX-300 small modular reactor at the Clinch River site near Oak Ridge in Tennessee. In January 2025, a TVA-led coalition applied for federal funding to accelerate construction of the first SMR with commercial operation planned for 2033.
Sweden
On March 14, 2022 Kärnfull Future AB signed a Memorandum of Understanding with GEH to deploy the BWRX-300 in Sweden.
Estonia
On February 8, 2023 Fermi Energia AS chose the BWRX-300 SMR for potential deployment in Lääne-Viru County
Lääne-Viru County ( or ''Lääne-Virumaa'') is one of 15 counties of Estonia. It is in northern Estonia, on the south coast of the Gulf of Finland. In Estonian, ''lääne'' means western and ''ida'' means east or eastern. Lääne-Viru borders Id ...
of Estonia
Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Ru ...
in the early-2030s
Notes
GEH describes the BWRX as the tenth version of their Boiling Water Reactors., following BWR 1-6, ABWR, SBWR, and ESBWR.
References
{{Reflist
External links
The BWRX-300 Small Modular Reactor
Nuclear power reactor types
Nuclear power