Will someone please tell Keir Starmer that the policy at the heart of his promise of a “fairer, greener” future will achieve neither goal, says Dominic Lawson in The Sunday Times. The Tory government has already spent billions on insulating people’s homes, and the results are dispiriting. A barely reported Cambridge study has found that while gas use dropped at first, by perhaps 7% in the first 12 months, any benefit had completely disappeared after four years. The reason is simple: seeing their bills go down, people started taking more hot showers and walking around with “fewer (or no) clothes on”. Economists call this age-old phenomenon the “rebound effect” – when steam engines became more efficient, coal use went up instead of down because people used the engines more.
Politicians are often “surprisingly ignorant” about how humans really respond to policies designed to change their behaviour. When Nicola Sturgeon introduced a minimum alcohol price of 50p per unit in Scotland in 2018, she boasted it would “save lives”. In fact, consumption among hardened boozers remained the same; they just spent less on things like food and utility bills. “In other words, the policy caused more, not less, misery to the very families it claimed to help.” It’s the same with Westminster’s efforts to tackle obesity with a sugar tax. Since food companies cut the amount of sugar in products such as ultra-processed breakfast cereals and yoghurts, sales have indeed plummeted. But overall British consumption of sugar has increased, as sweet-toothed consumers just get their fix elsewhere. Often, obvious solutions prove to be anything but.