Wikiepedia defines "Earth Hour" as an annual international event created by the WWF (World Wide Fund for Nature/World Wildlife Fund), held on the last Saturday of March, that asks households and businesses to turn off their non-essential lights and electrical appliances for one hour to raise awareness towards the need to take action on climate change.
Earth hour 2009 is scheduled for 28th MArch 2009 from 8:30 PM t0 9:30 PM local time. The earth hour website hopes to raise awareness by switching of the lights for one hour. However, earth hour might end up leading to higher energy consumption than on normal days. Since, electrical appliances such as refrigerators, air conditioners, heaters etc. will also be switched of for just one hour.
These electrical appliances have to spend more energy in reheating or recooling the surface or room after the end of the hour. As reported in earth hour 2008, New Zealand's power consumption during Earth Hour was 335 megawatts, higher than the 328 megawatt average of the previous two Saturdays. Similarly in Calgary, Canada power consumption actually went up 3.6% at the hour's peak electricity demand.
Is earth hour a great idea, implemented without thinking of the science behind it? Hopefully the organisers will make sure such wastage of power does not occur.