Concentional Nuclear Power Reactors in the World

Uranium (Nuclear Minerals) / Nuclear Power - Economics, Design, & Industry

Date posted: 12/18/16

Updated in late 2016, WNA reports about the main conventional types of nuclear reactor. A nuclear reactor produces and controls the release of energy from splitting the atoms of certain elements. In a nuclear power reactor, the energy released is used as heat to make steam to generate electricity. In a research reactor the main purpose is to utilize the actual neutrons produced in the core. In most naval reactors, steam drives a turbine directly for propulsion. The energy released from continuous fission of the atoms of the fuel is harnessed as heat in either a gas or water, and is used to produce steam. The steam is used to drive the turbines which produce electricity as in most fossil fuel plants. Oddly enough, the first nuclear reactors on Earth operated naturally in a uranium deposit about two billion years ago. These were in rich uranium orebodies and moderated by groundwater. The 17 sites of known fissioning at Oklo in west Africa, each less than 100 kW thermal, together consumed about six tonnes of that uranium. It is assumed that these were not unique worldwide. Canada also has very high-grade deposits and should show some signs as well when mined. Today, reactors derived from designs originally developed for submarines and large naval ships generate about 85% of the nuclear electricity in the world. The main design is the pressurized water reactor (PWR), which has water at over 300 C under pressure in its primary cooling/heat transfer circuit, and generates steam in a secondary circuit. The less numerous boiling water reactor (BWR) makes steam in the primary circuit above the reactor core, at similar temperatures and pressure. Both types use water as both coolant and moderator, to slow neutrons. Since water normally boils at 100 C, they have robust steel pressure vessels or tubes to enable the higher operating temperature. Another type uses heavy water, with deuterium atoms, as moderator. Hence, the term light water is used to differentiate. Read on.