The 3 MW (thermal) boiling water reactor (BWR) used 93.20% highly enriched uranium fuel. Prototypical generation II reactors include the PWR, CANDU, BWR, AGR, older VVER and RBMK. It has additional functionality in advanced versions of the BWR. All reactors were built using BWR technology. The reactors at this plant were BWR 3 and BWR 4 models. This causes the immediate cessation of steam flow and an immediate rise in BWR pressure. In a BWR, the containment strategy is a bit different. ANL used its experience from the BORAX experiments to design the BWR. The BWR concept was developed slightly later than the PWR concept. Both units are General Electric boiling water reactors (BWR). A newer design of BWR is known as the advanced boiling water reactor (ABWR). Three BWR units were built, that today delivers about 10% of Sweden's electrical supply. Unlike PWRs, Boiling water reactors (BWR) do not use steam generators. It has one unit (one reactor), a boiling water reactor (BWR) manufactured by GE. A "boiling water reactor" (BWR) uses demineralized water as a coolant and neutron moderator.