Millions of households are facing bill increases of more than £400 as the gas crisis causes further suppliers to collapse.
Two more energy firms with a combined 800,000 customers, Avro Energy and Green Supplier, went into administration yesterday.
Dozens of other companies are under threat including Bulb, which supplies 1.7million homes.
Customers on cheap tariffs with failed firms face being bumped up to the capped rate of £1,277 – a rise of at least £400.
Energy watchdog Ofgem described the situation as ‘unprecedented’ and confirmed bills would rise further.
The bleak warning came as food chiefs said supply problems caused by shortages of drivers and farm workers were deepening.
‘Our concern is that the pictures of empty shelves will get ten times worse by Christmas and then we’ll get panic buying,’ said Andrew Woolfenden of Tesco.
Twelve industry groups, led by the National Farmers’ Union, predicted the situation would get worse without a new visa regime to draw in foreign workers.
Customers with failing energy firms will be switched to new suppliers charging much higher tariffs, which is likely to add at least £400 extra to the cost of heat and light.
Meat manufacturers have warned that shoppers are likely to face higher prices as a result of the surge in CO2 costs
Two more energy firms with a combined 800,000 customers, Avro Energy and Green Supplier, went into administration yesterday. Dozens of other companies are under threat including Bulb, which supplies 1.7million homes