P Sampath, the current CFO, moves to a new role as the President of Business Optimisation and Improvement for Essar Energy plc, the company said in a press statement.
Both appointments are effective from April 1.
Maheshwari moves to Essar Energy from Anil Ambani Group firm Reliance Power where he was CFO since 2004.
An electrical engineering graduate, Maheshwari has MBAs from XLRI, Jamshedpur and London Business School.
"At Essar Energy, he will report to Naresh Nayyar, Chief Executive Officer of Essar Energy plc," the statement said.
Maheshwari, who has over 19 years of experience in project and corporate finance, investment banking and treasury management, had joined the Reliance Group in 2004
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