Energy Efficiency: Gas vs. Electric

I have to admit that this energy efficiency project of ours has been very empowering.  It is simply empowering to learn about a topic, really any topic.  But this topic allows you to have more power over your finances.  That’s always a cool thing.  Someone asked me about the cost of gas versus electric, so I thought I would post it here.

I had always heard that gas was cheaper than electric, but then there was always the side comment “but check, because it really depends on the price you pay locally for gas and for electric.”  And we are on propane which is much more expensive than natural gas, so that really muddies the water.

We moved into this house and kept the electric water heater and clothes dryer for over a year.  I felt proud and frugal that the 14-year-old heater was still working and that our friend Pat’s mother’s 30+ year old Maytag clothes dryer was still in service.  When I started on this cause to improve our electric bill, I decided to be thorough and look into all of our appliances, but a part of me said “obsession is good, but keep that start-up cost in mind:  new appliances are not going to pay for themselves.”  That part of me was very wrong.

I was amazed to find out the cost of our old electric appliances.  First, they are inefficient because they were manufactured in a time when efficiency mattered less.  Second, they could not have been at their prime and, thus, must have been even more inefficient than when they were manufactured.  Third, it costs us twice as much to run an electric appliance as it does to run an equally efficient propane appliance.  Here’s how you figure it:

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We know that 1 kwh of electricity generates 3,412 BTUs of heat.

And 1 gallon of propane equals 91,600 BTUs.

1 kwh = 3412 BTUs

1 gallon propane = 91,600 BTUs

91,600/3,412 = 26.84 = the number of kwh equivalent to burning one gallon of propane.

If buying one gallon of propane is cheaper than buying 26.84 kwh of electricity, propane is cheaper.

Here, our kwh did cost us 22 cents per kwh but with reduced usage, but we are now paying about 14 cents per kwh for much of our electricity with our reduction in usage.

So if propane is cheaper than $3.76 per gallon (14 cents x 26.84), then propane is cheaper to operate.

Propane here costs $1.59 per gallon.  It is 2.4 times cheaper than electric to generate the same heat.

Prices may fluctuate.  Propane prices may skyrocket in the future.  But the huge difference in cost now makes it an easy decision for me to shoulder the risk of future increases.

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This information sent me out to research gas refrigerators where I discovered that they tend to be less efficient than their electric counterparts (and more expensive to purchase).  In the process I found a great chest freezer which we could convert to a refrigerator and use as a back-up refrigerator on our porch.  Of course, what we didn’t know was that the transition from a 60 cubic foot refrigerator to a 17 cubic foot model would be so easy.  It doesn’t look like we’ll need the back-up refrigerator after all.