Nearly 1.5 million customers have been hit in just two weeks by energy firms collapsing under soaring gas prices.
Avro Energy and Green ceased trading on Wednesday and their 830,000 combined customers face being switched to a new, potentially more expensive, provider.
Green’s boss, Peter McGirr, told the BBC he had done nothing wrong and said bigger firms would soon face problems.
However, the government has cooled on the idea of loans to the industry, says BBC business editor Simon Jack.
McGirr predicted: “You will see larger suppliers feeling the pain as well and they will come cap in hand for a bailout.”
He criticized the government for supporting US fertilizer firm CF Industries to restart its fertilizer factory, which produced carbon dioxide used in the food industry as a by-product, while allowing energy firms to fail.