How Nuclear Power Can Transform Electric Grid and Critical Infrastructure Resilience
Terrestrial Energy submitted its IMSR-400 design to the Canadian Nuclear Safety Commission ( CNSC ) for a “ pre-licensing vendor design review ” in April 2016 ( CNSC 2020 ). The NRC and the CNSC selected the IMSR-400 as the focus of their first “ joint technical review of an advanced , non-light water nuclear reactor technology ” in August 2019 ( NRC 2019 ). The review process is on-going .
X-energy Xe-100 SMR
X-energy ’ s Xe-100 reactor is a helium-cooled , pebble-bed high temperature gascooled reactor . Each reactor is rated at 200 MWt / 75 MWe ( X-energy 2017 , X-energy 2018 , X-energy 2020 ). With a core outlet helium temperature of 750 º C , the Xe-100 is designed to produce both electricity and process heat with high pressure steam temperatures as high as 565 º C . X-energy ’ s NPP concept integrates a block of four Xe-100 modules . Thus a 4-pack X-energy NPP would be rated at approximately 300 MWe . Each of the four Xe-100 modules consists of a Xe-100 reactor , its helium cooling system , a steam generation system employing a single helical coil steam generator , and one turbine-generator subsystem . The pebble fuel is comprised of 15.5 % enriched Uranium Oxycarbide ( UCO ) kernel , tristructural-isotropic ( TRISO ) particle fuel in a graphite matrix . According to X-energy , the low power density of the Xe-100 (~ 30 times lower than traditional light water reactors ) enables completely passive shutdown cooling of each reactor ( rNPP FR 5 ). Therefore , the Xe-100 does not require safety-grade electric-driven reactor cooling systems . X-energy asserts that one Xe-100 design requirement is that no disruption in the conventional ( non-nuclear ) island of the plant can produce a reactor trip ( rNPP FR 3 ). When coupled with other design features , it is likely this design requirement would render the plant relatively invulnerable to Grid anomalies ( rNPP FR 2 ). X-energy also asserts the Xe-100 concept will have the ability to perform “ rapid load following in real time within the power range of 100-40- 100 %” of rated generating capacity ( modest attainment rNPP FR 1 ) ( X-energy 2018 ). Each reactor module has the capacity to reject ~ 25 % of its rated power as waste heat when isolated from the Grid , and the plant can be operated indefinitely at this power level in Island Mode ( rNPP FR 4 ). A single Xe-100 can be black started from onsite diesel generators with no need for offsite power ( rNPP FR # 6 ), and a single Xe-100 module can provide all the housekeeping electric loads for the other three modules in the X-energy NPP ( X-energy 2018 ).
X-energy has is engaged both with the U . S . NRC ( NRC 2020e ) and the Canadian Nuclear Safety Commission ( CNSC 2020 ) in pre-licensing discussions and vendor design reviews .
Major Barriers and Challenges to Development and Deployment of rNPPs and rCIIs
There are a number of cultural , technical , institutional , economic , and regulatory barriers to enhancing Grid and CI resilience , regardless of the path and technol-
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