FTSE 100 firm Drax Group, operator of Yorkshire's Drax Power Station, previously used Tulchan Communications for its financial comms.
The seven-strong pitch list included Tulchan as well as the likes of Maitland, Pelham PR and Luther Pendragon.
The brief, understood to be worth in excess of six-figures, incorporates UK financial communications and an element investor relations remit.
Drax Group floated its shares on the London Stock Exchange in December 2005. Drax Power Station provides around 7 per cent of the UK's entire supply of electricity.
Luther Pendragon will continue to advise on Drax Group's corporate PR, while Imagen oversee the local PR.