Npower confirmed it had submitted a bid. Centrica, EDF Energy, SSE, E.ON and Scottish Power declined to comment.
A spokeswomen from Ofgem said “We’ve had lots of interest (in the tender),” Ofgem has up to 14 days to choose a new supplier for GB Energy’s customers. GB Energy said on Saturday that it was no longer trading after a quick rise in energy prices and its inability to forward buy energy meant its business had become untenable. In recent months, energy suppliers had grown increasingly concerned about the possibility of a small supplier going under as wholesale power and gas prices have spiked ahead of the peak-demand period in winter.
Ofgem updated its rules last month, allowing any supplier stepping in to take over customers of a bankrupt supplier to recoup the cost of reimbursing outstanding customer credits by increasing energy bills.