The electricity and gas supplier is seeking greater integration between its direct marketing and digital activity, which it is increasingly using as a key customer acquisition channel.
The business has been held for the past five years by direct marketing agency Miller Bainbridge. The agency is not repitching due to conflict with client Thames Water, whose parent RWE owns utility company Npower.
The review, which is being carried out by the Haystack Group, is being overseen by Powergen's head of direct marketing and e-commerce, Andrew Franklin.
Powergen reviewed its creative advertising business in 2002 and subsequently appointed ad agency Rainey Kelly Campbell Roalfe/Y&R.
Rainey Kelly handles all its TV work, including its high-profile sponsorship of ITV weather and its involvement with rugby.
The latest review does not including Powergen's media planning and buying business, which is handled by Initiative.
Last August, Powergen signed up as a Tesco Clubcard's biggest rewards partner to try to boost loyalty among its 8m customers.
Powergen began a TV campaign earlier this year to raise awareness of the tie-up and push the message that for every £1 the consumer spends on their energy bill, a Clubcard point is awarded.
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