![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Pumpless_light_water_reactor.jpg/640px-Pumpless_light_water_reactor.jpg&w=640&q=50)
Light-water reactor
Type of nuclear reactor that uses normal water / From Wikipedia, the free encyclopedia
"LWR" redirects here. For other uses, see LWR (disambiguation).
The light-water reactor (LWR) is a type of thermal-neutron reactor that uses normal water, as opposed to heavy water, as both its coolant and neutron moderator; furthermore a solid form of fissile elements is used as fuel. Thermal-neutron reactors are the most common type of nuclear reactor, and light-water reactors are the most common type of thermal-neutron reactor.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Pumpless_light_water_reactor.jpg/320px-Pumpless_light_water_reactor.jpg)
There are three varieties of light-water reactors: the pressurized water reactor (PWR), the boiling water reactor (BWR), and (most designs of) the supercritical water reactor (SCWR).