How is nuclear energy produced in nuclear power plants?

Answer 1

Operators at STP Units 1 and 2 use pellets of uranium to heat water and create steam. The pellets are fixed into fuel assembly control rods inside the reactor. When the control rods are withdrawn, a reaction called fission begins.

During fission, uranium atoms split as they absorb subatomic particles called neutrons. This process releases energy and additional neutrons, which then split other atoms. The controlled reaction heats water circulating through sealed, stainless steel piping. The water is pressurized to 2,300 pounds per square inch (PSI) to keep the water in a liquid state at 600 degrees Fahrenheit. The sealed system, the primary loop, passes through huge vessels called steam generators. Inside the generators, the heat produced from the primary loop causes a separate system of cold water, pumped from cooling ponds, to boil. Much like a boiling pot of water on a stove, the hot water generates steam.

The wet steam is turned into dry steam and sent to a series of turbines outside a four-foot thick concrete containment wall fixed with hundreds of pounds of steel rods. The pressurized steam moves over the turbine blades causing it to spin. The steam passes through the series of turbines, which are connected to a generator by a long shaft. The mechanical motion powers the generator to create electricity.

After it turns the turbine blades, the steam is fed into a condenser and cooled by water from STP's reservoir. The condensed water is then pumped back to the steam generators and the cycle starts again.

Answer 2

A U235 (an isotope of Uranium) atom's nucleus splits apart spontaneously (spontaneously means without any outside help) into two smaller atoms through a process called nuclear fission. When it does split apart, the nucleus releases both energy and subatomic particles, including a neutron particle. A U235 nucleus will also undergo fission with outside help if it is struck by a neutron.

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The spontaneous rate of U235 fission is not sufficient to generate usable amounts of electricity, so nuclear power plants concentrate the U235 into specially shaped bundles. By concentrating the U235 closely together, when one atom's nucleus does spontaneously split apart, its released neutron strikes a neighboring atom, which causes that nucleus to split apart, in turn releasing another neutron, which causes yet another nearby nucleus to split, and so on. This process is called a chain reaction.

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The chain reaction is throttled using control rods that govern exactly how many neutrons are available to split U235 nuclei. A controlled reaction allows the right amount of free neutrons to maintain fission at a constant, desired level.

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Since each act of nuclear fission releases energy, the fission chain reaction releases a great deal of heat. The nuclear power plant uses this heat to boil water, and drives the resulting steam through large turbines, and these turbines spin generators that produce electricity.

Answer 3

Nuclear power plants produce energy in the same way as most other conventional power plants, the difference is that they use nuclear material for fuel. The nuclear fuel is in the form of rods made from nuclear material. The rods are arranged close together in a pool of water, causing the water to heat up and turn to steam. The steam turns giant turbines which generate electricity.

Answer 4

A nuclear power reactor uses the nuclear fission reaction to generate heat. Extremely pure water at very high pressure is routed through the reactor, which heats the water. This is called the "primary" loop.

Hot water in the primary system then goes through a heat exchanger in which the heat is transferred to a secondary loop. The primary water becomes slightly radioactive, but it never mixes with the secondary loop water, which does not become radioactive.

The secondary loop water is allowed to expand into high pressure steam, and the steam drives a turbine. The secondary water then goes through another heat exchanger and a condenser, which condenses the steam back out into water. None of this water is allowed to escape; it's a completely closed cycle.

The turbine driven by the secondary steam is used to spin a generator, which generates electricity.

Answer 5

The energy is produced in the reactor core. A link is provided to another question that will speak to the working of the core.