Moderator note: split from https://www.railforums.co.uk/threads/ecml-mml-major-power-problems-09-08.188171/page-9#post-4147074 Sounds like a grid failure, it seems that various parts of the country are affected, London, Cardiff and the Liverpool as well as parts of east Anglia seem to be affected. National rail is reporting problems in the first 3 areas. This could either be caused by a sudden loss of generation, or a failure of one of the trunk high voltage lines which distribute power around the country. What tends to happen is that first fault causes surges in other transmission lines, which in turn fault, leading eventually to grid separation. The following article explains the cause behind a major blackout in the NE USA in 2003 https://en.m.wikipedia.org/wiki/Northeast_blackout_of_2003. Fluctuations in frequency are a sign of an unstable grid. The problem with wind and solar power is that they are not always on, you need other technology to provide a base load and to back up when when they are not available. There are 3 choices in the UK, fossil fuels, nuclear and hydro. With the closure of coal fired stations, and the imminent closure of the older nuclear stations this situation will get worse.