Market failure exists when the competitive outcome of markets is not 
efficient from the point of view of the economy as a whole. This is 
usually because the benefits that the market confers on individuals or 
firms carrying out a particular activity diverge from the benefits to 
society as a whole.
A government drive to encourage people to switch tariffs is a laughable response to our broken energy system (Shop around for savings, energy customers told,
 18 October). The big six energy companies supply 99% of British 
households and make massive profits from a stitched-up market. They 
stand to make many billions by keeping us hooked on increasingly 
expensive fossil fuels. Consumers are already being hit hard by the 
energy companies' stranglehold – they alone do not have the power to 
break it. Instead of cosying up to the big six and cutting funding for 
energy efficiency, the government should be creating a fair system that 
provides energy we can all afford – that's why our Final Demand campaign
 is calling for an urgent public inquiry into the behaviour and 
influence of the big six.
Andy Atkins
Friends of the Earth
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