Profits for ScottishPower, the renewable energy generator, were improved by windy conditions last year – but the supplier took a hit as Britons cut back on energy consumption in the face of higher bills. The energy generation and supply group, which is owned by Spain’s Iberdrola, said underlying group profits in 2022 had risen 3.6% to £1.6bn on a year earlier. However, ScottishPower made a loss of £18m in its retail business – which, with 4.7 million customers, is the sixth biggest supplier – after slumping from a £3m profit the year before. ScottishPower said that total volumes of gas it supplied to households, sourced from wholesale suppliers, fell 18.3% in 2022 while electricity use was down 4.5%. The figures are among the first indicators of the scale at which households and businesses reduced their energy usage amid higher bills last year. The price of gas surged after Russia’s invasion of Ukraine, pushing up already high wholesale gas costs, as well as power prices. The costs fed through into household bills and the government stepped in to cover part of consumer bills through the energy price guarantee. Ministers encouraged the public to reduce their energy consumption with an advertising campaign. A relatively mild winter in the UK is also expected to have reduced gas demand. ScottishPower said its retail profits were also hit by the cost of buying energy at higher prices before the government guarantee, which covers the wholesale costs for suppliers, was introduced in October. The company hopes to recover a “significant proportion of the losses incurred in 2022” during this year. Profits in ScottishPower’s renewables business, which includes Whitelee, the UK’s largest onshore windfarm, near Glasgow, rose 24% to £730m, helped by windier weather, selloffs of IT and offshore assets, and higher energy prices. Windfarms produced a record amount of Great Britain’s electricity last year. A levy on electricity generators was introduced at the start of the year to capture windfall profits made as wholesale power prices surged. However, ScottishPower said gains made through higher energy prices had been partly offset by charges paid to National Grid to balance supply and demand. The company plans to invest £10bn in the UK by 2025, but Keith Anderson, ScottishPower’s chief executive, has urged the government to allow renewables projects to be developed more quickly. “The extreme volatility in the energy market has reinforced the urgent need to decarbonise the economy,” Anderson said. “A crisis caused by fossil fuels can only be fixed for the long term by speeding up investment in the fuels of the future. Clean energy and green grids are the answer. We need to build more and we need to build them faster.” ScottishPower and its peers are being scrutinised by regulator Ofgem over the installation of prepayment meters. The Guardian reported last month that the supplier had stopped clawing back debt through the meters, but Ofgem later ordered all installations to stop after it emerged that British Gas debt agents had ignored customers’ vulnerabilities to fit meters. On Wednesday, Iberdrola said profits had risen 10% to €13.23bn (£11.6bn) in 2022 as growth in the US and Brazil had offset a poor performance in Spain.