The Joint European Torus (JET) tokamak owned and operated by the UK Atomic Energy Authority (UKAEA) produced the largest amount of energy during its final round of deuterium-tritium experiments. In 5 seconds, a ground-breaking record of 69 megajoules of fusion energy was produced, using only 0.2 milligrams of fuel. This exceeded the previous world record it set in 2021, when it produced 59 megajoules over 5 seconds.