Propane or electric back up?

[GT26]

I'm trying to explore the possibility's for my wood and solar water, back up power.
2700 sf tight well insulated ranch style home in N Idaho. About 40,000 heat calc. Radiant in floor.
My two choices are propane ( $2.90 gal & rising )and electric (.064 kwh & stable hydro ).
I have used several on line calculators and unless I have missed something electricity seems to be about 1/2 the cost?
I'm thinking of using a large instant hot water heater as a back up for the radiant.
I relies this will involve a large power supply infrastructure, but the up front cost of the unit is about half the cost of a propane unit.
Another variable is that I can help pay for electricity with solar and wind, I cannot however, make my own propane.
What am I missing?
Thanks, Tim

 

[WhitePine]

Propane is a non-starter, even @ twice your power rate. You aren't missing a thing.

In this neck of the woods (similar to higher electric rates), folks are dumping propane as fast as they can.

 

[woodsmaster]

Thats some cheap elec. If you don't foresee an increase in rates go elec.

 

[Como]

It would be reasonable to see propane going up faster.

For me the issue was the cost of an upgraded supply, 3 phase etc which made it impractical.

You can get electric boilers.

 

[GT26]

It would be reasonable to see propane going up faster.

For me the issue was the cost of an upgraded supply, 3 phase etc which made it impractical.

You can get electric boilers.

David, my thoughts on propane as well.

As far as elect boilers are concerned, from what I've gleaned off the internet it dosent seem to be the most efficient way to go.
I'm no expert, but this is what I'm getting. Its more efficient to instant heat the water you need because elect is "on / off" IE no wasted idling.
If you elect heat to storage you have some stand by losses.
I'm sure this varies with system size and design.
Feel free to shoot holes in this theory!
Thanks, Tim

 

[in hot water]

Electric by a long shot.
Look at the Thermolec or ElectroMN electric boilers. They are small volume, modulating boilers. One if not both include an outdoor reset function to modulate the output temperature. They are designed to be boilers, and have ASME tags. I think you would be better off with an electric boiler than a electric tankless heater.

hr

 

[benjamin]

Don't know what you're priorities are or what you're willing to do on your own but...

Electric is the least efficient energy source, but $.06 is a no brainer. If you were interested in a used geothermal heat pump ($1,000) they're available and easy to install, hard to beat heat at $.015/kwh. Another DIY option with or without the geo is using a standard water heater (about $200 each) one for heat and one for hot water. For heat just hook up two 30A circuits, one for each element, giving 11kw or almost 40,000 btu.

I doubt you can pay for much of that $.06 electricity with solar or wind, unless you're DIYing a used 40KW or bigger, or unless you're talking about "carbon-greenwashing".

 

[huffdawg]

Why is electricity the least efficient? if you use a 1500 watt baseboard do you not get 1500 watts out if it?
I installed a Buderus mod.con. boiler and I like it as far as functionality,but paying for the propane really pisses me off .
Should of done my home work a little better prior to purchasing it . I think electricty would of been around half the price.
But my original intentions were to use as a back up and use wood full time . There are rumours around here that electricty is going up by50% in the next 3 yrs.
Kind of like buying in the stock market. you never really know.

 

[Como]

In totality, generating and transmission.

 

[benjamin]

If you're paying $.06/kwh for electricity then it can go up 50% and still be cheap by most people's standards. Probably still cheaper than propane.

Nuclear or fossil fuel electricity is a low efficiency heat, if your hydro is really hydro eh then that inefficiency doesn't apply to you. Heat pumps can be much more "efficient" than resistance, regardless of the electric source, but electric resistance is a good choice for backup when the backup is rarely used and no AC is needed.