GLEEP, which stood for Graphite Low Energy Experimental Pile, was a long-lived experimental

nuclear reactor A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...

Oxfordshire Oxfordshire is a ceremonial and non-metropolitan county in the north west of South East England. It is a mainly rural county, with its largest settlement being the city of Oxford. The county is a centre of research and development, primarily ...

, England. Run for the first time on August 15, 1947, it was the first reactor to operate in western Europe. It was built at the

Atomic Energy Research Establishment The Atomic Energy Research Establishment (AERE) was the main Headquarters, centre for nuclear power, atomic energy research and development in the United Kingdom from 1946 to the 1990s. It was created, owned and funded by the British Governm ...

, a former

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...

airfield, near

Harwell Harwell may refer to: People * Harwell (surname) * Harwell Hamilton Harris (1903–1990), American architect Places * Harwell, Nottinghamshire, England, a hamlet *Harwell, Oxfordshire, England, a village **RAF Harwell, a World War II RAF airfield, ...

in Oxfordshire (then in

Berkshire Berkshire ( ; in the 17th century sometimes spelt phonetically as Barkeshire; abbreviated Berks.) is a historic county in South East England. One of the home counties, Berkshire was recognised by Queen Elizabeth II as the Royal County of Berk ...

), in an aircraft hangar. It was a

graphite Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...

moderated Moderation is the process of eliminating or lessening extremes. It is used to ensure normality throughout the medium on which it is being conducted. Common uses of moderation include: *Ensuring consistency and accuracy in the marking of stud ...

, air-cooled reactor and used 11,500 natural uranium fuel

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

-clad rods inserted into 676 horizontal fuel channels. With a normal power output of just 3

kilowatt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Wa ...

s, it was initially used for investigations into reactor design and operation, and later for the calibration of instruments for measuring

neutron The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons beh ...

flux. It had an exceptionally long life for a reactor of 43 years, being shut down in 1990. The fuel was removed in 1994 and the

control rod Control rods are used in nuclear reactors to control the rate of fission of the nuclear fuel – uranium or plutonium. Their compositions include chemical elements such as boron, cadmium, silver, hafnium, or indium, that are capable of absorbing ...

s and external equipment the following year. A project to completely dismantle it was started in 2003 and completed in October 2004.

External links

Research Sites Restoration Limited

Aerial photographs of reactor site
{{authority control 1947 establishments in England 1990 disestablishments in England Graphite moderated reactors Nuclear research institutes in the United Kingdom

Gleep GLEEP, which stood for Graphite Low Energy Experimental Pile, was a long-lived experimental nuclear reactor in Oxfordshire, England. Run for the first time on August 15, 1947, it was the first reactor to operate in western Europe. It was built at ...

Nuclear technology in the United Kingdom Research institutes in Oxfordshire Vale of White Horse Defunct nuclear reactors

See also

External links