<a href="https://www.thenationalnews.com/business/energy/2023/04/27/energy-security-at-risk-as-uk-set-to-miss-2035-green-electricity-target/" target="_blank">Coal-fired power</a> has made an unexpected return in Britain after the <a href="https://www.thenationalnews.com/tags/national-grid/" target="_blank">National Grid</a> requested the reactivation of two units at the <a href="https://www.thenationalnews.com/world/uk-news/2023/03/30/uk-aims-to-meet-climate-targets-by-boosting-nuclear-hydrogen-and-carbon-capture/" target="_blank">Ratcliffe-on-Soar</a> plant in Nottinghamshire. This move, compelled by a surge in energy demand amid a heatwave, breaks a 46-day streak of coal-free <a href="https://www.thenationalnews.com/business/energy/2023/03/02/renewables-generated-enough-energy-to-power-every-uk-home-this-winter/" target="_blank">electricity generation</a> in the UK. The decision was triggered by a <a href="https://www.thenationalnews.com/business/energy/2023/03/07/uks-national-grid-prepares-for-tight-power-supply/" target="_blank">surge in use</a> of air conditioning, according to Greenpeace, as the nation experienced temperatures above 30ºC for the first time this year. Meteorologists are forecasting a 45 per cent probability of a hot summer in the UK. Air conditioning comprises about a fifth of the total electricity consumed in buildings worldwide, with increased usage expected as the heatwave continues in many parts of the globe. Uniper, the owner of Ratcliffe-on-Soar power station, brought one unit into action on Monday morning and warmed up a second for the evening peak demand. The plant had been on standby since winter, when concerns were raised about potential blackouts due to reduced gas supply from Russia to Europe. The increasing demand coincides with a decline in wind energy generation and continuing maintenance at Torness nuclear power station in Scotland. The plant was taken offline on June 1 for planned maintenance, which is expected to last for several weeks. Britain's energy situation is further complicated by a fault in the North Sea Link interconnector, which transmits power between Norway and the UK, causing a reduction in electricity supplies. This decision to resort to coal-fired power generation has drawn criticism from environmental campaigners. Greenpeace UK’s political campaigner Ami McCarthy said: “It is a sign of failure that the National Grid is turning to one of the most polluting forms of power generation to deal with a summer heatwave that we know has been made worse because of climate change.” She urged the government to upgrade the energy grid and tap into renewable energy networks such as solar power. The National Grid has advised consumers to enhance the energy efficiency of their air conditioning units through steps such as cleaning the machine’s reusable filter, closing windows and doors, and blocking the Sun's light and heat by drawing curtains. Jess Ralston, head of energy at the Energy and Climate Intelligence Unit, said reliance on coal power, particularly as a backup, could be reduced with the help of more efficient energy trading systems and improved storage solutions such as batteries. Ms Ralston’s prediction coincides with the planned closure of all units at the Ratcliffe plant by September next year, as part of the UK's phasing out of coal. To further conserve energy, the Electricity System Operator (ESO) – part of the National Grid – encourages households to shift their power usage away from peak hours through its demand flexibility service. Last month, it reported that households and businesses had saved enough energy over the winter to power 10 million homes. The National Grid adjusts the amount of electricity being produced to match how much is being used, through what is known as the balancing market. In this set-up, power plants such as Ratcliffe are paid to either step up or scale down production based on current demand. As more fluctuations in supply are expected, the grid operator plans to reduce excess demand during peak times, thereby mitigating the need for pollution-heavy plants to generate power. Solar panels, while harnessing energy from the Sun, tend to lose efficiency during extreme heat and operate at their best within temperatures of 15°C to 35°C. When it becomes hotter than this, solar-panel efficiency can diminish. A report by the UK Energy Research Centre last year estimated 1.5 million air conditioning systems were in use in the UK, representing only 2 per cent of all households. But the use of air conditioning has still increased significantly in recent years, with the number of systems increasing by 50 per cent between 2012 and 2022. The increase has come while the number of hot and humid days in Britain has also risen.