Backup heat source, not wood
steve2021_5a
| Posted in Energy Efficiency and Durability on
About to build a single story over a basement house in zone 5a in western North Carolina. All electric. I was considering a wood stove for heat/cooking in the event of an extended power outage, but everything I am reading says that is probably a bad idea for something that would get used a few days a year at most. Is there a best practice for backup electricity? Solar + battery? Propane generator? Gas generator? I’d like it to be able to cover 3 week outage.
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Estimate how much energy you use in a three week period. Calculate how much it would take to store that much energy in propane, fuel oil or batteries. Figure out how you would convert the fuel into usable power, what the efficiency of that conversion is, and adjust the quantity accordingly.
I think once you run the numbers you'll lower your sights.
Steve,
You may find these discussions useful:
https://www.greenbuildingadvisor.com/article/where-to-invest-when-preparing-your-house-for-power-outages
https://www.greenbuildingadvisor.com/article/planning-for-back-up-power
I live on a coastal road that experiences the most power outages in BC each year - on average over 20, and some have been five or six days long. Many people do have wood stoves, but the recent trend is for propane generators. Apart for power, the propane can also fuel heaters, a stove and barbecue. One other big advantage is not having to frequently re-fuel the way you would with a gas generator.
Are you using the right source for your zones? I don’t think NC is zone 5.
Yancey Co - there are 3 counties along the Tennessee border that make a little 5a island due to elevation :-)
Good to know! Propane is your friend here. The solar makes sense in general just skip the battery.
Steve,
Solar plus battery isn't cost-effective. What you want is a generator -- either gasoline-powered or propane-powered.
If you are thinking only about space heat, then you should get a propane-fueled space heater with through-the-wall venting. Several manufacturers, including Empire, make propane heaters that don't require electricity.
I saw this recommendation poking around the GBA articles last night, but had not come across one that worked when the power is out - I think this is what I need. Will look for Empire and any other brands you might think of that can work with no power. Bonus points if there is one that has a hot plate option, though a camp stove on the porch or a few cans of Sterno would also work.
Empire is the only brand of propane-fired space heaters with models that don't require electricity, as far as I know, and I've researched it fairly extensively. None have a hot-plate option. You can get an inexpensive camp stove that would serve that purpose; just be sure to use it outdoors due to the toxic emissions.
My state, Maine, has the worst-rated electric utility in the country and we often experience power outages. I try to design fossil-fuel-free homes but unless clients are in the rare areas that don't lose power regularly, I recommend a propane-fired standby generator. If that's too expensive, do what I do and use a portable gas-fired generator with a manual lockout switch at the electrical panel.
Steve,
The big downside of an integrated propane generator sized to meet most of the house's needs is that they consume a lot of fuel even when there are minimal loads on them.
I'd choose a barbecue with burner over a camp stove.