 Both were supercritical water reactors; the first unit used 67 tons of uranium enriched to 1.8%, while the second unit used 50 tons of uranium enriched to 3.0%.The first unit had an indirect steam cycle, while the second had a direct one.Although they were comparable in power to the Shippingport Atomic Power Station, the Soviet planners regarded the Beloyarsk reactors as prototypes.