Megawatt Valley is a term applied to a geographic location which houses a large number of electricity generating stations. Historically in the United Kingdom this applied to the coal-fired power stations of the lower Trent Valley. In the mid-1980s, the valley's 13 facilities generated up to a quarter of the power demand for England and Wales. A shift to gas-fired power stations saw many of the Megawatt Valley facilities close down. The term was then associated with an area of Yorkshire centred on the River Aire that was home to Ferrybridge C, Eggborough and Drax power stations. Of these facilities only Drax remains in operation. In the United States the term has been applied to an area of West Virginia, home to five power stations.