Europe's biggest coal-fired power station, Drax in North Yorkshire, is weighing up a £1.9bn bid from US electricity giant Constellation Energy.
Drax says the bid does not match its market value
The offer comes as the management of Drax completes its plan to float on the London stock market in December.
Board members are considering Tuesday's approach, but added that the offer was below the site's current market value.
The complex near Selby, which employs 560 staff, is owned by creditors after going into administration in 2003.
Major US supplier
It ran into difficulties in 2002 after its biggest customer, the electricity supplier TXU Europe, failed to pay a £50m bill. TXU was later put into financial administration, a step toward bankruptcy.
Constellation Energy is a leading supplier of electricity to large commercial and industrial customers in the US and is the nation's largest wholesale power seller. It also imports coal into the UK.
It is bidding as part of a consortium which also includes US investment fund manager Perry Capital.
Its offer would provide creditors and shareholders with a full cash alternative to the current plans for a possible listing, a Constellation spokesman said.
The consortium has asked Drax to allow it to inspect the company's books - a process known as due diligence - in order to make a firm offer.
A Drax statement said: "The board will consider any proposal which it believes will deliver fair value to its shareholders, whilst continuing preparations for a refinancing and listing."