"So have they finally admitted the big plan to sell off our infrastructure does not increase competition or lower prices"
I didn't notice any such admission in the article you linked to. You've made the assumption.
I think few people can seriously suggest that nationalised utilities would lead to lower fuel costs; it's ludicrous to suggest otherwise. The only way that a government can influence the price of a nationalised utility in favour of the consumer is by subsidy from the public purse - in effect we would all still pay in the end. Nationalised industry is traditionally wasteful in terms of labour costs, and riddled with inefficiencies, a nationalised power industry would be a paradise for militant union leaders. The argument in favour of public ownership was always 'it means you don't have to make a profit, so there's a benefit over ordinary companies.' The argument doesn't stand up however, the profit margin is eaten up by waste and inefficiencies, and the world is a very different place to that of 50 years ago. Nationalising the power industry would be a disaster.
The simple fact is, fuel costs will rise in the short,medium, and long term as mineral fuels continue to dominate the industry. It's the reason why governments should be vigorously developing the nuclear power industry instead of faffing about telling us to switch suppliers.
We don't need a government Minister telling us that consumers should "vote with their feet and switch to a different supplier", we're intelligent enough to work that out for ourselves, although for many people it isn't quite as straightforward as the Minister seems to think - as you've pointed out.
I am on a consumer panel for one of the big power suppliers, and they have recently asked me to look at their various suggestions for improving their service - one of which is making it much easier for consumers to switch suppliers. These companies are well aware of the pressures from the market, but they need pushing. Additional competition from smaller suppliers will ramp up the pressure.