Yes, this is another one of those international “everyone do something” events. Tomorrow the World Wildlife Fund is asking everyone to turn off their lights (and hopefully most other energy-using appliances as well) for an hour. It will be 8:00pm in California when Earth Hour starts, so there will probably still be some daylight, but our apartment gets so little natural light that we’ll be in the dark anyway. I have no idea how they are planning to monitor the success of this, though electricity output numbers will be interesting, but there is an event for it on Facebook so you can register your intention to participate there. It currently has just short of 800,000 members, which is a drop in the ocean for the world population but not bad for Facebook. More details from the official web site.
Kevin has just commented that various people are blogging about what a sham the whole thing is because it won’t actually do much to reduce energy consumption. Here’s an example. Power station economics is, of course, one of my areas of expertise, so here’s my take.
Saying that energy consumption won’t drop because coal power stations are hard to turn off is, I’m afraid, nonsense. One of the awkward things about the electricity industry is that storage of electricity is very difficult. You pretty much match supply to demand at all times. WWF claims that last year’s Earth Hour, which happened only in Sydney, resulted in a 10.2% drop in electricity demand (see below for discussion). The Australian grid will have to have handled that somehow. Some of it will have come from the fact that ramping a coal-fired station up and down can be done rather quicker than turning it on and off. Some of the excess energy will probably have been used to prime pumped storage plants in Snowy, because pumping water up a hill for release through turbines later is one way you can “store” electricity. The issue of the notorious brown coal plant in Victoria is irrelevant as demand won’t have dropped low enough to affect them.
So electricity production will have been reduced, and that will probably have saved some carbon emissions. It may also have been a pain in the butt for the folks who run the electricity market. The odd shifts in consumption may have been difficult and expensive to handle. The good news is that in 2007 Earth Hour was at 7:00pm in Sydney, a time at which consumption would have been dropping anyway, so I don’t think it would have been that difficult. Doing it at the same time world-wide is harder for electricity utilities to manage, but I suspect it won’t be that much more difficult that the effect produced by the soccer World Cup final.
As to how much electricity was actually saved, that’s open to debate. This paper from the University of Chicago claims that the actual drop in consumption was a) less than claimed (because people would be shifting consumption to other times of the day) and b) statistically dubious (because consumption is variable so it is hard to prove just how big a drop occurred). That makes a reasonable amount of sense. There will have been a drop in consumption, but it is hard to say how big it really was.
But you know, this isn’t the point. Anyone who thinks that turning off their lights for one hour a year is going to stop climate change on its own is just plain daft. In terms of energy emissions, it is a drop in the ocean. If Earth Hour has any purpose, it is as a political statement by millions of people around the globe that climate change is important, that it is something we care about.
Look at it this way, today happens to be Blog Against Torture Day, so fine, here I am saying that I think that use of torture is largely ineffective as an intelligence-gathering tool and deeply harmful politically. Is this going to save a single person from torture today? Of course not. Does that mean that it wasn’t worth saying? Don’t be silly. Earth Hour is just the same. It isn’t the carbon saving, it is the statement.