Tuesday, February 25, 2014

Switch to better bulbs and fuel up for free?

Don't you love sensational headlines? Don't you love pie-in-the-sky concepts that get peeled back to considerably less when you get there? I read an article a few weeks ago that just keeps rolling around in my brain because it seems like one of those headlines. But my own experience does back it up. Essentially, this person bought a Chevy Volt and was surprised to see his electric bill go down. When you read into the article, you learn that there was an unmentioned variable. He had changed from incandescent to compact fluorescent bulbs in his house at the same time he brought the Volt home. And that made all the difference. So, a little math (Feel free to let your eyes glaze over until you get past this little piece. I will put the conclusion in bold text at the bottom.)

Let's say you have a mixture of incandescent bulbs, but they average out to 75watt bulbs (75¢ per bulb per month), and you are the average American with 60 bulbs in your house. If you swap those 60 bulbs  for 60 17watt LED bulbs (17¢ per month per bulb), you get some math like this:

60x75¢=$45 per month with incandescent
60x17¢=$10 per month with LED

So, the swap would get you $35 per month in electric bill savings.
(all of this is based on 3 hours of use per bulb per day, and that is pretty conservative)

According to the EPA in 2011, your Volt will cost you $601 per year if you run only the electric motor

$601/12=$50 per month to drive a Volt.

So, if you go with NRDC and EPA averages, and you are the average American, your bill will go up $15 per month if you swap all your bulbs and start driving (and charging) a Volt.

Other math (for those who want to dig a bit deeper):

The cost of swapping those 60 bulbs will be between $600 and $800.
For the past year, we have been averaging $75 per week in our fairly efficient family pickup.

I think it's time for me to do some investigating at home. Maybe it's time for some grudge matches, maybe the Whirlpool refrigerator vs. the Zero motorcycle. I better bust out the the kill-a-watt meter and sharpen a pencil for this one. Check back next week to see how the grudge matches are going.

May math be on your side!

The Treehugger article that triggered this post

Links to resources for my math:

EPA Fuel Economy for a 2011 Volt

NRDC Light Bulb Comparison

Number of Bulbs per House