Sustainable energy – without the hot air

Many of the current plans to reduce our energy use are headline grabbing and claim that even small changes could reduce our energy consumption. However, many of these proposals lack any figures to back up their claims, and when they do they are selected to sound large and to make an impression, rather than aid the discussion.

Professor Mackay's lecture will cut through these claims. "To understand these 'huge' issues we need numbers, not adjectives. We need numbers that are simple, human sized, and memorable. No millions, no billions, no Terawatt hours, no exajoules," says Professor Mackay. "In this talk I'll present simple back of envelope calculations to see how our energy consumption stacks up compared with conceivable sustainable production."

He will explore some of the fallacies that are promoted around cutting our energy use, such as switching off a mobile phone charger when not using it. "The truth is that leaving the phone charger on uses about 0.01kWh per day. This means that switching the phone charger off for a whole day saves the same energy as is used in driving an average car for one second," says Professor Mackay. "Switching off phone chargers is like bailing the Titanic with a teaspoon."

Professor Mackay has recently published a book on sustainable energy, 'Sustainable energy - without the hot air', that is available from bookshops and for free from the website http://www.withouthotair.com/.

The lecture 'Sustainable energy -without the hot air' will take place in the Babbage Lecture Theatre, New Museums Site, from 7.30-9pm. A Spotlight on Science lecture of the Cambridge Science Festival, it is sponsored by Cambridge University Press and TTP Group.