The UK’s electrical grid is vulnerable to blackouts due to rising summer temperatures, with outdated equipment unable to cope with extreme heat. In a worst-case scenario, power failures could trigger widespread outages, similar to those experienced in Spain and Portugal last month. The Met Office predicts temperatures of 40°C or higher will become regular occurrences by the end of the century unless urgent global action is taken.
Source: https://www.newscientist.com/article/2478825-extreme-heat-poses-spanish-style-blackout-threat-to-uk-electrical-grid