Backup fuel cost comparision

  • Active since 1995, is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Not open for further replies.


New Member
Oct 7, 2011
North Idaho
I hope this is the right place to post this as it's not primarily a wood burning question.

Here's my situation: I have a 4800' shop in North Idaho that I will be working in full time. As the thermometer is sitting at 10 degrees this morning I would like to get some heat turned on and soon. Pex is in the floor, just need to get a heat source to it. The long term plan is to install a wood boiler with storage, when I close my eyes and daydream I see a Garn in the attached shed out back. But, due to finances and time that is a project for next year.
Once the wood burner is in I will also want a backup heat source, so I want to put that in now and run it this winter.

Natural gas is not available here so my choice is between propane and electric. Using the calculator on another part of the site it appears my fairly cheap hydro electric will be much more economical. Current propane price is $2.15 a gallon giving a million BTU cost of $28.08 at 85% efficiency. Current electric cost is 6.3 cents per KWH giving a million BTU cost of $18.46 at 100% efficiency. My electrical service has plenty of capacity for a large boiler so that is not an issue. So the question is whether this is as cut and dried as it seems or am I missing any part of the cost equation?

Thanks for any input!


Minister of Fire
May 15, 2011
Central Maine
If you are truly looking for short term heat...

what about a modine type heater off propane.

Or a trailer furnace type hot air unit running off heating oil.

if you want to go hydronic and with wood.. I would think you would look to get something quick and cheap in there for short term. The difference in costs of fuel isn't going to be enough to sway you if it's just for a year or two.

what am I missing from what you said. every penny you spend on a system this year is slowing you down from buying the garn.



Minister of Fire
Sep 15, 2011
Nova Scotia
Did you compare oil too?

I think I would definitely rule out propane, and man do you have some cheap electricity. I did a similar oil/electric comparison for here a couple months ago, using oil at $1/litre, and electricity at 0.15/KWH (current rate). I got $26 oil vs. $44 electric/Mbtu.

I think I'd lean towards electric with your rate - it would also be a much cleaner install with no fuel storage & lines etc.


Minister of Fire
Nov 7, 2009
Yes, it is as cut and dried as it seems. The only part you might be missing is that the electric equipment may be much cheaper than the propane equipment. A down and dirty "boiler" could be a used water heater run on two circuits at 11,000 watts or almost 40,000 btu/hr. Add a circulator pump and you're in business.


Minister of Fire
May 23, 2010
Ithaca NY Area
I'd agree....electric seems like the way to go and presumably an electric boiler would be much cheaper. Only issue would be an extended power'd be cold and starting to worry about freezing. But, it takes a long time to freeze up a concrete slab...and presumably a little generator could keep the pumps moving water, even if there's no added heat.

And you could likely add a little heat with a small generator, certainly enough to stop freezing.

I think I pay about 0.18/kWHR. Keep that low cost hydro coming!
Not open for further replies.