The design of electricity systems has failed to catch up with the revolution in renewable energy. Competitive electricity markets, established in many countries to try and minimise costs, are actually suffering the greatest price rises. This is not because governments elsewhere use taxes to subsidise electricity (though some do), but because in wholesale electricity markets, the most expensive generator sets the price.

If renewables are now so much cheaper, why can’t consumers buy electricity directly from them and avoid paying the gas and carbon costs?