"The agreement envisages stage-wise acquisition of First Energy by Thermax over the next four to six years. First Energy focuses on consumers in the commercial and home cooking segments," Thermax said in a filing to the BSE.
First Energy's brand Oorja, a combination of a 'micro-gasification' stove and biomass-based pellet fuel, is adopted by several customers as a substitute to fossil fuels such as LPG and diesel, it added.
First Energy, which is an alternative energy solutions company, had posted Rs 42 crore revenue in 2014-15.
"We are happy to be associated with First Energy. The partnership offers Thermax synergy and new opportunities in the commercial space to serve customers with alternative and cost saving solutions," Thermax MD & CEO M S Unnikrishnan said.
Mahesh Yagnaraman, co-founder and CEO of First Energy, said, "As a leader in heat transfer technologies and applications, Thermax is a valuable strategic partner for us.
"We are confident that this partnership will enable Oorja to scale up faster, building on our passion to innovate and enhance consumer satisfaction.