Five Percent: Conserve Energy

Climate Change Is Important: Energy Conservation is the First Step

April 8, 2007

How Our Conservation Works: Year over Year Data

Category: Big Things,Conservation,Household,Save Electricity,Take Actions – Tom Harrison – 11:52 am

We started our conservation efforts in late September 2005, about the time I started this blog. Using data from our electricity bills, which report the number of Kilowatt Hours (KwH) used in each billing cycle, transferred the data to Excel and made the chart below.

Bottom line: we have reduced our total consumption of electricity by more than 40% on average. A little better than my 5%, eh?

We heat the house and water, dry our clothes, and cook with natural gas, except that in our finished basement we have several electric baseboard heaters. Otherwise, the seasonality of our electricity use is presumably related to the number of hours of sunlight, and perhaps electricity used to power the heat circulation pumps.

The orange bars are from the year before we started our conservation efforts (2004 through Sept 2005); the light green bars are our first 12 months, and the dark green bars are the next.

Click for Full Size Image

Click for Full Size Image

One thing that is not factored into this calculation is “degree days”, which may affect how much we need to heat (or cool). Also, our kids are getting bigger. In both cases, I am not sure which years were colder/hotter, or whether older kids use less or more. I think whatever effect there may be is minimal anyway; most of our electrical use is in lighting, refrigeration, and TV & Computer.

How did we accomplish this? About 1/2 of our light bulbs are compact fluorescent (CFL). We and the kids are disciplined about turning off lights we don’t need, and not turning them on in the first place. We no longer have CRT screens for our computers. We have a modest wide-screen LCD TV instead of a smallish (25″) CRT TV. When the TV is off, all the other boxes (except TiVo) are off. Our computers are set to standby and hibernate when not in use. We have the basement heat set to 55 degrees, and insulated the walls of the finished section, so only need to turn on the heat there when the kids need to use the room (it heats up in about 10 minutes). The house heat on a programmable thermostat (this only affects the electricity used to run the circulator pumps) in this calculation. We insulated several areas of the house, notable the sun-room attic. We use ceiling fans in the summer and only use the two window air conditioners when necessary, maybe 3 or four days, last summer.

In short, we have made almost no sacrifices yet have used dramatically less electricity: a bit more than 30% reduction in the first year, increasing to a total reduction of more than 40% by the next year. In terms of today’s cost for a kilowatt-hour of electricity, we save around $700/year, or about $60/month. This savings easily pays for any incremental costs (e.g. insulating, CFL’s, monitors) we have incurred … probably in the first year (unless you count the TV :-).


  • Minimal sacrifice
  • Minimal cash outlay
  • Over 40% reduction of electrical use
  • $700/year savings
  • Good karma (working on quantifying that)
  • No-brainer

I’ll work on natural gas, and gasoline next. Natural gas will be hard; gasoline will be a little easier. Both should reflect some significant gains.


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