Another four energy suppliers have gone bust in a single day as historic gas market highs continue to rip through the UK's energy market amid fresh fears that Russia may curb gas supplies to Europe. The energy regulator, Ofgem, said the collapse of four small energy suppliers on Tuesday would leave about 24,000 households in need of a new supplier, and bring the total number of bust energy companies to 17 since the start of September, affecting more than 2 million households.