I've been monitoring my electric meter on a daily basis for nearly 13 weeks now.
That's one–quarter of a year — and I have reached some tentative conclusions in that time.
I really need at least a year's worth of data — but that will only tell me about my usage in that year alone. You can't draw any long–term conclusions based on short–term observation.
Take this past week for example. Here in north Texas, we have 100° days, on average, about a dozen times a year. Some years, we have more than a dozen. Last year, for example, my memory is we had about 10 weeks of days in which the temperature was in triple digits.
It was comparable to — but never as severe as — the summer of 1980, which is still remembered as the mother of all hot summers. I spent part of that summer here in Dallas, and my memory is that we reached the 100° mark before lunch most days. By the middle of the afternoon, it was frequently over 110°.
Last summer wasn't like that. There may have been as many days when it reached triple digits, but there were never as many days when the temperature went way past 100° before the sun went down. (Don't get me wrong. I believe hot is hot. But extreme heat is something else entirely.)
In fact, there were several days last summer when the temperature just barely made it to 100°, and there were several times when the local media wondered if the streak of 100° days would end.
I didn't start monitoring my meter until April so I have no data concerning the cold months. However, data from this February wouldn't have been very helpful. It was unseasonably warm all month — quite a contrast from the February of 2011, when an ice storm influenced most people's plans for Super Bowl week in north Texas.
A typical February falls somewhere between the two extremes.
In June around here, temperatures are usually in the 90s. I've seen a few Junes when we had mostly daytime highs in the 80s, and I've seen others when the temperatures were in triple digits. Both were anomalies.
Last summer wasn't typical here, either, just a little hotter than normal.
My bills continue to show my meter readings as estimates, and all you have to do is divide the number of kWh claimed by the number of days in the billing period to figure out the daily consumption average. And, for at least the last four months, the daily average upon which my bill has been based is 30 kWh.
I am no mathematician, but I do know that if some number represents an average, then there must be figures in the calculation that are both lower and higher than that average.
In the case of electricity consumption, if I average 30 kWh daily, there must be some days when my use is in the 20s and some days when my use is well into the 30s.
So — if I really want to save money, and I do — it is helpful to know the kinds of conditions that are likely to increase my electricity consumption.
I live alone in a one–bedroom. The other elements on my monthly utility bill — i.e., water and sewer — are pretty consistent. The thing that tends to vary is electric consumption, and the variable on that is the use of heat and air conditioning.
In the last three months, I have seen for myself that when I don't have to run the heat or A/C — or if I only have to use one or the other sparingly — my consumption drops dramatically.
As a result, my consumption was virtually negligible in the spring. But there were times in the spring when the temperature was unseasonably warm, and I had to run my A/C a little. On those occasions, I could see a spike in my use.
On days when the high was no greater than, say, 75° or 80° (and the low was in the 50s or 60s), I seldom had to run the heat or the A/C — and my consumption was often in single digits.
If the temperature dropped into the 40s or rose into the 80s, I could see a difference in my usage — typically into the teens.
By and large, May was warmer, with temperatures that routinely went into the 80s, sometimes low 90s, and my daily consumption reflected that. In the billing period for May, my daily consumption averaged slightly more than 20 kWh.
This month has been hot, and I know my daily consumption figures have shown that. I fully expect my average for June to be around 30 kWh — the only month in which that assumption by my utility company will be correct.
The 100° days of last week appear to be over, so my consumption should drop as we ease into the 90s.
In fact, I'm already seeing that. A few days ago, when temperatures were 100° or, more frequently, higher, I was using around 40 kWh a day just to cool my apartment to around 84°. There were times when it took all the self–control I could muster not to adjust my thermostat to 82°.
Yesterday's high temperature was around 99°, and my consumption in the last 24 kWh appears to have been 32. This morning's reading is 3900 on the nose. Yesterday's reading was 3868.
Perhaps, in the next few days, I can lower my daily consumption to 30 — or a shade or two below. Today's high is supposed to be 98°, and tomorrow's high is supposed to be 95°.
Then it's supposed to start going back up — forecasts indicate we'll be back in the 100° range by Independence Day.
