Better article here: https://www.world-nuclear-news.org/Articles/Chinese-HTR-PM-Demo-begins-commercial-operation https://www.world-nuclear-news.org/Articles/Ch

Better article here: https://www.world-nuclear-news.org/Articles/Chinese-HTR-PM-Demo-begins-commercial-operation https://www.world-nuclear-news.org/Articles/Chinese-HTR-PM-D... > "The HTR-PM features two small reactors (each of 250 MWt) that drive a single 210 MWe steam turbine. It uses helium as coolant and graphite as the moderator. Each reactor is loaded with more than 400,000 spherical fuel elements (‘pebbles’), each 60 mm in diameter and containing 7 g of fuel enriched to 8.5%. Each pebble has an outer layer of graphite and contains some 12,000 four-layer ceramic-coated fuel particles dispersed in a graphite matrix." Note that Chernobyl was graphite-moderated and water-cooled, but hot graphite and steam is a bad combination, tending towards the generation of (explosive) hydrogen and carbon monooxide gases during loss-of-coolant type accidents. The helium coolant avoids this process, and can sustain higher operating temperatures so has industrial uses, somewhat ironically in the petrochemical sector: > "The major purpose of HTR-PM is to co-generate high temperature steam up to 500℃ and electricity. It is cost effective currently in the Chinese market to supply steam and electricity for the petrochemical industry to substitute the burning of natural gas and coal." It seems like a pretty safe design with some unique capabilities, although it'd be interesting to see the total cost-per-pellet inputs (each 6 cm pellet generates as much power as 1.5 tons of coal prior to its retirement, but manufacturing each pellet is probably not that cheap).