The Advanced Gas-cooled Reactor (AGR) is a type of nuclear reactor designed to generate electricity. It uses carbon dioxide as a coolant and graphite as a moderator, allowing it to operate at high temperatures. AGRs are known for their efficiency and safety features, making them a significant part of the nuclear power landscape in the United Kingdom. AGRs typically use enriched uranium fuel and can produce a large amount of electricity with low greenhouse gas emissions. They are designed to have a long operational life, often exceeding 30 years, and are part of the UK's strategy to maintain energy security while reducing reliance on fossil fuels.