There will be "unintended consequences" from Labour's energy freeze plan as a result of the decline in the price of oil, Sam Laidlaw, the outgoing chief executive of Centrica has warned.Ed Miliband, the Labour party leader, has stressed his party intends to freeze energy costs if they win the general election in May, but Laidlaw believes the move could hurt customers rather than help them."I think we're in a world now where because long-term the market seems to be softer - and obviously you've seen the oil price phenomenon in the last month or so - the price freeze is probably going to have some unintended consequences if it were to be put in place," he was quoted as saying by the Telegraph."I've no idea whether it will be or not - that will depend on the electorate. I think the clear concern is that people will have bought some of their energy further forwards than they otherwise would have done, in order to mitigate the effects of the price freeze. And that means that retailers' ability to take advantage of a softer price are limited."Laidlaw added that he did not feel downbeat over the public scrutiny Centrica has faced in recent years."People often forget the hugely valuable role that Centrica plays in the quality of peoples life, keeping the lights on, security of supply, trying to do this in an affordable way, and actually impacts Britain's competitiveness and everybody's standard of living and ultimately inflation rates," he said."With that, inevitably, comes some fairly strong views but I think that goes with the territory, and in an election cycle, the volume will go up."