Money alert: Changes to energy bills

The energy Watchdog Ofgem is forcing gas and electricity firms to change the way people buy their energy, by reducing the number of core tariffs available to four for electricity and four for gas.

The tariffs must all be presented in the same way, with a standing charge and single-unit rate. The aim is to make it easier for us to compare different deals from different companies.

There will also be more encouragement for people to switch, with energy users given personalised information on the cheapest tariff for them based on their own energy consumption.Ofgem is trumpeting the changes as the biggest reforms of the energy-retail market since competition began.

But MP John Robertson, who sits on the energy select committee, warned that cheaper tariffs could disappear bringing "a price rise for some people".