Fourth-generation reactor will supply power and process heat.
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Episode Transcript:
When the world’s first purely commercial nuclear power plant went online at Shippingport, Pennsylvania in 1957, it was hailed as the beginning of a new age of low-cost power production. Electricity was predicted to become “too cheap to meter.”
Although reactor technology improved for subsequent design generations, the cost of nuclear energy has been similar to fossil fuel generation, although nuclear advocates claim that the unusually high regulatory burden in the U.S. artificially boosts those costs. Nuclear plants traditionally have been large-scale projects, commonly taking over a decade to build in America—although the Japanese have built plants in 3 to 4 years from the first concrete pour to grid connection.
New, so-called “Fourth-Generation” small reactors promised to eliminate this bottleneck by creating mass-producible, truck transportable small reactor units that don’t require site-by-site safety certification and can be easily removed for refurbishment or decommissioning.
Replacement of existing nuclear and fossil fuel generation with SMRs is a logical development, but an underreported use case for the small reactors is outside of the grid.
Chemical industry giant Dow and Rockville, Maryland-based X-energy have announced that a small modular reactor will be installed at a Dow Gulf Coast production facility under the U.S. Department of Energy’s Advanced Reactor Demonstration Program. A $50 million joint development agreement will result in the installation of an X-energy Xe-100 high temperature gas cooled reactor to produce both electric power and process heat for steam. Costs will be split between the Department of Energy’s ARDP and Dow.
The engineering project will include the preparation and submission of a construction permit application to the U.S. Nuclear Regulatory Commission. The Xe-100 reactor design is significantly different from current large-scale commercial reactor technology. It is built around a core structure containing 220,000 graphite pebbles with TRISO fuel. TRISO is an acronym for tri-structural isotropic particle fuel, consisting of a core of uranium which is encapsulated in three layers of carbon and ceramic-based materials.
The reactor is cooled with helium gas operating at 750° C and 6 MPa of pressure. The helium is looped through a heat exchanger to produce 565° C steam at 16.5 MPa of pressure to drive turbines or for process heat.
In the X-energy application, the fuel is fabricated into billiard-ball-sized spheres with the interstitial spaces between the spheres allowing helium gas to flow. TRISO fuel is noteworthy because it allows intrinsically safe reactor designs, greatly simplifying reactor engineering and maintenance, both of which are key to small reactor economic viability. TRISO fuel can also be U.S. sourced, from BWX Technologies Inc. who operate licensed production facilities in Lynchburg, Virginia.
If successful, the project may have a significant and twofold effect: the rapid decarbonization of many process industries and a rethink of the geography of the industry. Since the beginning of the Industrial Revolution, access to low-cost power has been essential when locating industrial enterprise. Transportation links to bring in raw materials and take out products have always been essential, but some industries such as electrolytic metals processing and electric arc steel mills require the availability of lots of low-cost electric power.
If heavy industry can cost-effectively generate their own power, and enjoy the benefits of process and space heat as a side benefit, then industrial plants may be located closer to inputs, markets or both. And in an age when demand for grid power for electric vehicle charging is predicted to explode, on-site power generation using small modular reactors can buffer industrial users from price spikes—and excess power may be sellable to utilities to defray costs at non-peak periods.
Self-powered, carbon neutral factories. The Dow – X-energy experiment may foreshadow a significant shift in 21st-century industry.
