My electric bill has gone up about $60-100 per month since I started folding. It’s hard to get exact numbers because I also added a couple computers. I always left my PCs on 24/7 anyway, so this is just the extra cost of running them at 100% load. My bill will go up this summer (rate increases from 7.77 to 8.92 cents/kWh), whereas my computers helped heat my condo in the winter (seriously).
My primary folding box, with four 9800GX2 graphics cards and a quad-core AMD proc, pulls about 1000W from the wall at 100% load. This accounts for most of my extra electrical cost - using the formula above, about $56 to $64/month depending on the electric rate. The average computer doesn’t use anywhere near that much power.
From an environmental/conservation standpoint, I think it’s more valuable to have my computers doing something useful rather than sitting idle (wasting electricity) while waiting for me to access them. Distributed computing is also a good way to raise the profile of various research projects among computer users. Plus, man-caused global warming and “peak oil” are hoaxes, so I’ll use as much electricity as I want. ;-)
BTW, I’m currently participating in an annual folding contest with another team, but I’ll be back on team 36120 in a few days.
Are you seeing any slowdown in awarding points on GPU work units? With two GPUs I expected to be producing more than I am.