by Heather Burns-DeMelo
Every once in a while, I read about something so profound that it works its way into my consciousness to the point that I go around telling everyone for years. The Story of Stuff was one, and the work of Cambridge University Professor David MacKay's is another.
David spent some time measuring the output of typical items in his flat...the toaster, the light bulbs, a phone charger...and made some startling discoveries:
All the energy saved in switching off your phone charger for one day is used up in one second of car-driving. The energy saved in switching off the charger for one year is equal to the energy in a single hot bath.
To provide one quarter of our current energy consumption by growing energy crops would require 75% of Britain to be covered with biomass plantations. To provide 4% of our current energy consumption from wave power would require 500 km of Atlantic coastline to be completely filled with wave farms.
If you fly to Cape Town and back once per year, the energy you use in that trip is nearly as big as the energy used by driving an average car 50 km per day, every day, all year.
Driving an average car 50 km per day uses 40 kWh per day. Covering 10% of the country with wind farms would yield 20 kWh per day per person on average.
How Many Light Bulbs? from Cambridge Ideas from Cambridge University on Vimeo.
For more information – go to David MacKay’s website: www.withouthotair.com