Energy regulator Ofgem is to tighten up the rules for new suppliers of gas and electricity after nine new entrants ceased trading.
The latest to collapse was Economy Energy, which ceased trading on Tuesday. Ofgem is looking for a new supplier for its 235,000 customers.
Mary Starks, Ofgem's executive director for consumers and markets, told the BBC that there was "room for improvement" in the licensing regime.
She also defended the new price cap.
This caps prices at £1,137 a year for an average dual-fuel customer who pays by direct debit.