Skip navigation

Monthly Archives: June 2008

Just to clarify, the vertical-axis scale on a plot has to be large enough to allow for discrimination among data points. The scale can certainly be chosen for dramatic effect, but I simply wanted to use numbers on the vertical axis that were all within a couple of orders of magnitude. In any case, an updated plot including data through 2007 is shown below. (This is in terms of energy consumption, instead of power consumption as in the previous plot.)

Annual US Residential Electrical Consumption per Capita

I originally chose Watts per capita because it can be mentally related to the number of 100-Watt incandescent bulbs each of us is responsible for running constantly in a given year. For example, during the 1977 calendar year, each American used the energy equivalent of 3.3 100-Watt bulbs burning for the entire year. That’s non-stop, 24/7 use. In 2007, that increased to 5.2 bulbs running throughout the year. My point was that life hasn’t gotten particularly better in that period, despite the increased consumption.

Another point: atmospheric CO2 levels, mercury deposition from power plants, etc. are dependent on the absolute magnitudes of combustive power production. In other words, we all pay the price–and our kids will pay the biggest price–for excessive consumption, energy and otherwise. It is worth repeating that these data refer to total residential consumption, which specifically excludes electrical use by commercial, industrial and utility entities.


Here, for all the world to see, are the electricity and natural gas consumption plots for the period from June 2005 through May 2008 for our house in Rapid City, SD. Our 1952 ranch-style abode is about 1300 square feet, including a highly inefficient garage conversion completed sometime in the 60’s. We blew an additional 1.5 feet of recycled newsprint insulation into the attic and installed a modern gas furnace, but are still contending with the single-pane windows. (The aluminum storm windows do help, and we use shrink-plastic film in winter.)

Monthly Electricity Consumption

Monthly Natural Gas Consumption

(Get the source spreadsheet so you can plot your own data–see below.)

The upward trends for both are best explained by the birth of our son in May of 2006. Though we’ve kept the house a bit warmer for him, this past winter’s natural gas use was held in check by more careful winterizing. In fact, the past winter was several degrees colder than the winter of 2006-7 based on the gas company’s statistics, so we likely would have had lower usage if the weather had been similar.

Also, to keep the bedroom warm for our athletic toddler, who insists on kicking off all covers regardless of room temperature, we tried using a radiator-style electric heater at night. Big mistake, as shown by the electrical peaks for February and March of this year. Finally, a Mac Pro has been in heavy use for video editing since September of last year. It consumes about 350 watts, including 2 monitors, and is responsible for some of the recent trending.

Although posting these stats feels a bit like hanging my underwear out on the clothesline, I think there’d be stronger social pressure to conserve if 1) we all had detailed knowledge of our own consumption patterns and 2) others could see our patterns, too. (Sort of like an eco-Facebook or green-MySpace.)

For reference, our household natural gas consumption is about 71% of the average for our climate region, and electricity, about 41%. (Our water heater, stove and furnace are natural gas.) I think that new windows would result in dramatically lower gas consumption.

I am cleaning up the spreadsheet I made to create the plots. If you want the “dirty” version, please email me at Otherwise, wait for the tidy version, which will include more regional climate info and specific data for cities around the US.