bemoreeco

Smoothly. Avoid dramatic braking and acceleration and use cruise control if you’ve got it. Move through the gears as quickly as possible, changing up before you hit 2500 revs per minute (2000 rpm for a diesel). Where possible, drive at a steady 55 miles per hour (90 kilometres per hour). It is up to 20 per cent more fuel-efficient than driving at 75 mph. Check your tyre pressure once a month because underinflated tyres can raise fuel consumption by 6 per cent. Don’t carry excess baggage. Each extra 25 kilograms decreases fuel efficiency by 1 per cent. And avoid short trips – a cold engine uses twice as much fuel as a warm one.

Is it worth recycling when stuff gets shipped to China and back in the process? Given the carbon footprint of all that, maybe we should just let the stuff rot

With recycling rates going through the roof, some countries don’t have the capacity to process all their waste. In the past 10 years, for example, waste paper exports from the UK have risen from 470,000 tonnes to 4.7 million tonnes per year and exports of used plastic bottles have gone from under 40,000 to 500,000 tonnes. China has a big demand for both materials, and its trade imbalance with Europe and the US means container ships would be heading home empty if they didn’t carry waste. According to a recent study by WRAP, shipping waste to China in this way uses 10 per cent of the carbon saved by recycling.

Can I save the planet by staying slim?

It’s unlikely. In May, Phil Edwards and Ian Roberts from the London School of Hygiene and Tropical Medicine did link obesity and global warming (The Lancet, vol 371, p 1661). They argued that obese people consume around 18 per cent more calories than the average and their greater mass means their vehicles require more fuel, so policies to encourage walking and cycling would not only improve people’s health but also be good for the planet. Perhaps such policies would provide short-term benefits, but in the long run they would be more than offset by the fact that people who stay in shape are likely to live longer, emitting tonnes of CO2 for every extra year of their lives. So being slim may be good for you, but is unlikely to benefit the planet.