Power generation utilities including country's largest power producer NTPC and Damodar Valley Corporation (DVC) owed about Rs 8,279.19 crore to state-owned Coal India, as on November 30.
"Power generation companies, like NTPC and DVC have an outstanding dues of Rs 8,279.19 crore to Coal India as on November 30, 2015," an official said.
While state-run power producer NTPC owe around Rs 500 to the coal PSU, DVC has an outstanding dues of around Rs 1,500 crore, the official said.
Power companies of states like West Bengal, Chhattisgarh, Rajasthan and Madhya Pradesh also owe dues to CIL, the official said.
An NTPC official said that it has not received any communication in this regard.
"NTPC's negligible amount may be due with Coal India, which is a routine matter," the official said.
The state electricity distribution companies, which buys electricity from power PSUs, like DVC owe significant outstanding dues to power firms as discoms are facing tough financial conditions, a Coal India official said.
"So this is can be seen as one of the reasons for the power generation firms owe huge dues to Coal India," the CIL official said.
In a bid to rescue almost bankrupt state electricity retailers, the central government had last month approved a scheme to rejig Rs 4.3-lakh crore debt of the utilities.
The Union Cabinet had approved the scheme to ease the financial crunch of power distribution companies or discoms that has impaired their ability to buy electricity.
The rescue plan, called Ujwal Discom Assurance Yojna or UDAY aims at reviving ailing state electricity boards and operational efficiencies of power distribution companies.
It envisages to reduce interest burden, cost of power and aggregate technical and commercial losses.
The scheme is optional and gets operationalized by signing a pact between states, state discoms and the Centre.
Some of the states that have given their in-principle approval for joining the UDAY scheme to the Power Ministry include Chhattisgarh, Andhra Pradesh, Jharkhand, Rajasthan, Punjab and Jammu & Kashmir.
Power and Coal minister Piyush Goyal had earlier tweeted that all states have expressed strong interest for joining UDAY and are at various stages of getting internal approvals.
"We remain confident of all the states joining UDAY and together creating an Ujwal Bharat," he had said.