Managing Used Nuclear Fuel
When fuel assemblies no longer produce enough heat in a reactor, plant workers replace them with new assemblies and reconfigure the remaining assemblies. Generally, about one-third of a reactor's fuel is exchanged every 12 to 18 months. Once it is removed from a reactor, the fuel is known as used fuel.
Once fuel assemblies are removed from a reactor, they are placed in pools at the plant. These pools are lined with concrete and steel. Used fuel pools keep the fuel under water at all times. Cool water circulates through the pool to remove heat. They take about five years to cool down.
While used fuel no longer produces enough heat to run a nuclear reactor, the fuel assemblies remain hot and emit radiation. The concrete and steel in these pools – and even the water itself – serve as a barrier from the used fuel’s radiation.
Once the used fuel is removed from these pools, it is stored in special concrete and steel containers called dry casks. These casks can be securely stored on-site at a nuclear energy plant or at an interim or long-term storage facility.
Open Fuel Cycle
In an open or “once through” fuel cycle, fuel assemblies are used only one time. The nuclear energy plant temporarily stores the used fuel assemblies on-site while they cool before sending them to an interim or long-term storage facility.
Closed Fuel Cycle
In a closed fuel cycle, the nuclear energy plant sends its used fuel to a reprocessing facility after cooling it on-site. During reprocessing, uranium is recycled into fresh fuel. With current technology, the recycling of used fuel can occur only once. As part of the UAE’s commitment to non-proliferation and a peaceful nuclear energy program, the reprocessing of used fuel assemblies is not permitted and will not be pursued.
Used Nuclear Fuel in the UAE
The UAE stores used nuclear fuel from the Barakah Plant on site while it cools.
The Federal Government of the UAE is developing its long-term storage policy for spent fuel, but ENEC must ensure the safe disposal of solid radioactive waste in accordance with the laws of the UAE and the legislation of the Federal Authority for Nuclear Regulation and the International Atomic Energy Agency.
The UAE still has plenty of time to make decisions about spent fuel management, especially given the fact that there is capacity for storing used nuclear fuel for 20 to 30 years in the spent fuel pool at the plant. The Government is considering the options available.