Report Card Day
I just got my utility bill for the month of March. I had really hoped that the changes over the last month would make an amazing difference in my bill. Okay, so I still hope for magic. ;-)
Here's the bottom line:
| Month | KWh | Therms |
| Jan | 583 | 129 |
| Feb | 892 | 79 |
| Mar | 814 | 34 |
So, that's a difference of 78 KWh between our February usage and our March usage. Or 8.7%. How much of that is warmer weather and longer days and how much of that is conservation? I don't have real good stats on that. But since most of my conservation has been changing to CFLs, and I've recorded my changes at One Billion Bulbs, I'm gonna use their numbers.
According to my account, I've changed 15 bulbs. They're showing estimated savings of $7.55. They're also currently using a figure of 9 cents per kilowatt hour for Colorado, which means they estimate my changes have resulted in nearly 84 fewer kilowatt hours being used. They don't have a filter that allows me to see savings during a date range, so this does include a few days of February usage.
Hmm. So, it looks like, based on very rough estimates, my 8.7% savings, or 78 KWh, can pretty much all be attributed to changing CFLs over the last month or so (84 KWh). That's pretty reassuring.
But numbers over 800 KWhs feel high to me. I got a quote on a solar PV system and the estimator said, "I'd be really surprised if you were using over 400 KWhs regularly." And yet my 3 bdrm house appears to be using nearly twice that regularly.
What I don't know is whether the estimator was commenting on one person living here or a couple or more than that.
| Month | # of people | KWh/person | Therms/person |
| Jan | 2 | 291 | 64 |
| Feb | 3 | 297 | 26 |
| Mar | 3.2 | 254 | 10.6 |
It is rather comforting to look at it this way. It makes it easy to see that it is worthwhile to share expenses with others, even if the bottom line numbers go up because actually the per person use is going down.
My solar estimate was $15,000 to supply 400 KWh of electricity per month off my own roof. The economics of that are pretty interesting... the system pays for itself in about 20 years assuming that KWh prices stay in the 10 cents an hour range. It pays for itself more rapidly if electricity costs go up... which is likely considering retrofitting power plants to sequester carbon and increasing demand for coal and natural gas worldwide. I am disappointed that 400 KWh isn't enough to make my household self-supporting. But maybe that's an indication that there's more to save. Hmm... how many more bulbs can I change before my roommates revolt? ;-)
