The Anil Ambani group-run company has already received approvals from the Competition Commission of India (CCI) and the shareholders for the 100 per cent stake sale in Reliance Energy, which it now expects to close by next month. RInfra and the Adanis had signed definitive agreement for sale last December for a consideration of Rs 18,800 crore, the company said, adding it will use the proceeds from sale to retire its entire debt and become a Rs 3,000-crore cash surplus entity. RInfra's Mumbai power business, known as Reliance Energy, is one of the largest private sector integrated power utility, distributing power to nearly three million residential, industrial and commercial consumers in the suburbs of Mumbai, covering an area of 400 sq km, catering to a peak demand of over 1,800 mw with an annual revenue of Rs 7,500 crore.