Across much of India, an energy crunch caused by the Iran war has prompted long queues for cooking gas cylinders. That is not a problem for Gauri Devi. On a stove with blue flames, she flips a chapatti flatbread, burning biogas produced from cow dung – an alternative fuel helping ease pressure on supplies. “It cooks everything,” the 25-year-old said in her courtyard kitchen in Nekpur, a village in Uttar Pradesh, about 90km (55 miles) from New Delhi. “If the pressure goes down, we let it rest for