'Microreactors' may eventually replace fossil fuels and huge power plants, IAEA says

An advanced fission plant concept design developed by a California-based company is the type of "microreactor" that could lead to replacing fossil fuels and huge nuclear power plants, an international power agency recently reported.

The Aurora powerhouse is one of more than a dozen microreactors (MRs) currently being developed worldwide by private companies and research groups, the International Atomic Energy Agency (IAEA) reported last month.

Developed by Oklo, Inc., the powerhouse is a fast spectrum reactor, currently under regulatory scrutiny. It could potentially operate for decades without the need for refueling using "high assay low enriched uranium fuel" and "is designed to function and self-regulate primarily using natural physical phenomena," the article said.

"The fission reaction can be used in many formats: small and large, different fuels, different ways to cool, and enable many different ways for business models and community interaction and ownership," Oklo Co-Founder and Chief Operating Officer Caroline Cochran said in the article. "The novel use of fission and the implementation of distributed, smaller plants can enable human development while minimizing resource use."

The report published in IAEA's September bulletin was written by Irena Chatzis, associate communication officer with the International Atomic Energy Agency in Vienna, Austria.

The Aurora powerhouse, also called the "Oklo powerhouse", is an advanced fission plant that received a site use permit late last year from the U.S. Department of Energy (DOE).

In its Dec. 2 announcement, Oklo described the Aurora Powerhouse as an "advanced fission clean energy plant design developed to power communities with affordable, reliable, clean power."

The Aurora powerhouse's advanced fission power plant, or "fission battery," includes solar panels as part of Oklo's claim that advanced fission and renewables can be used to create a clean, high reliability microgrid to deliver energy to communities.

Oklo, founded in 2014, is based in Sunnyvale, California.

MRs such as the Aurora powerhouse, and small modular reactors (SMRs), likely will change the landscape of nuclear power delivery away from huge power plants and cooling towers, according to the IAEA report.

"SMRs and MRs provide low carbon energy like large nuclear reactors do, but they are smaller, more flexible and more affordable, so they can be used on smaller power grids and be built in hard-to-reach places where large reactors wouldn’t be practical," IAEA SMR Technology Team Leader Frederik Reitsma said in the report. "Many are designed to provide non-electrical services in addition to electricity production, adding to their clean energy benefits and cost-effectiveness."

SMRs are forecast to generate up to 300 megawatts of electricity, according to the report.

MRs can be expected to generate a fraction of the SMRs forecasted amount, up to 10 megawatts of electricity based on design.

MRs and SMRs are noted for modularity with "passive and built-in systems that enhance safety, the ability to efficiently and flexibly generate energy to meet fluctuating demands, and simpler designs that are faster and less complex to construct than current reactors," the report said.

MRs and SMRs also "have more factory-based manufacturing possibilities" that could reduce construction time, which makes both easier and cost-effective to "reproduce for additional deployment," the report said.

"Large nuclear reactors are a major undertaking and require substantial long-term investment, which is feasible and appropriate for some situations," Reitsma said in the report. "For others, however, SMRs and MRs can be a more realistic and faster approach and sometimes the only way to cost-effectively access nuclear power. When you combine this with effective financing and market policies, it opens up nuclear power to a wider range of users and makes it a more competitive and attractive option on the energy market."