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There is no modern system that "just works" whatever the weather. We had an ice storm when I was growing up and lost power for 3 days. Wood stove worked great

There is no modern system that "just works" whatever the weather. We had an ice storm when I was growing up and lost power for 3 days. Wood stove worked great as a backup, not much else would have.

hedora 4y ago
Dual source heatpump + Solar + battery + propane generator might be OK. The batteries would need to somehow be kept warm though. (The solar and battery are there to stretch out the propane supply until the delivery truck gets past whatever road blockages exist, and then addresses the inevitable shortage cause by the electricity going out.) Of course, an 80% efficient wood stove costs a small fraction as much as the above setup, and is more reliable.
- flyingfences 4y ago
  > The batteries would need to somehow be kept warm though. If I were buying such a setup, I'd just put the batteries in the basement. Plenty of space, and it stays 40-50°ish year-round here.
  - adql 4y ago
    Not that many homes are built with basements nowadays. Water to water heat pump with pipes being directly under building's basement might've been pretty neat solution tbh, if you're digging for basement anyway might as well put some piping there for the heat pump
    - pfdietz 4y ago
      (Googles) I didn't realize basements were falling out of favor. Interesting!
- Scoundreller 4y ago
  Too bad few backup generators have the capability of dumping their heat output into the home via coolant loops or exhaust heat capture.
  - dsfyu404ed 4y ago
    Because the residential ones are mostly small enough to be air cooled. Exhaust heat is fine in theory but HN would be screaming bloody murder if even one person died from CO as a result of a shoddy install or cracked heat exchanger so it's basically a nonstarter if you're a big juicy lawsuit target like a business. While there's nothing fundamentally different from a forced hot air furnace the novelty factor makes fending off the ambulance chasers more expensive than it's worth.
    - hedgehog 4y ago
      The way to do it is probably to colocate the generator with the condenser unit and use a thermostat-controlled second loop to move heat to/from the main refrigerant loop as needed. This gives some options to keep the generator from getting too cold to start as well as recover waste heat when it's up to temperature.
- whazor 4y ago
  Heatpump also needs to be kept warm, but those pumps do that themselves.
- falcolas 4y ago
  Given the need to maintain a ~100°F temperature differential on at least 6 days so far this year (at least here in Montana), a solar-augmented generator is probably not enough. Our heat pump has a natural gas backup, and even it was running at about a 60-70% duty cycle on those days. All that to say: +1 on a wood stove backup.
- aidenn0 4y ago
  Starting a generator below a certain temperature becomes hard too (most lubricants do a nice impression of putty when sufficiently cooled). As an aside, if you have a large free-standing propane tank you probably don't need to worry about stretching out the supply. I've known people who use propane as their primary heat source and can go a month between deliveries. Even assuming your propane heater + heat pump is 1/3 as efficient, that should give you 10 days of heat.
throwaway894345 4y ago
Why wouldn't a gas furnace have worked?
- flyingfences 4y ago
  Gas/Oil Furnaces/Boilers still need electricity to run the blower (air into the firebox) and circulator (hot air/water from the unit to the rooms) motors.
- smiley1437 4y ago
  FWIW older gas water heaters that use a standing pilot flame and piezoelectric ignition can run without electricity. Combustion products are vented passively by convection. With this type, as long as you've got gas, you can have hot water. Maybe huddle by the hot water tank? For the sake of efficiency, most newer gas water heaters need electricity for ignition as well as to power the fan that exhaust gases. All gas furnaces will need electricity to run the fans.
hirundo 4y ago
The woodstove is my primary heat source, it isn't modern, and it works regardless of the weather. But it isn't difficult to image circumstances where it fails, since it almost happened to me. I had a gout attack that made it very painful to bring in firewood. If I had central heat it would have been a matter of flipping a switch on the thermostat. Instead it got so cold that I just suffered the pain, like walking on a broken foot. After that I got my central heat fixed. It's nice to have both options.
sgent 4y ago
For a backup wouldn't a gas baseboard heater or room heater work? I know they are not in favor due to fire and CO issues, but for an emergency backup they worked well enough for our parents and grandparents.

There is no modern system that "just works" whatever the weather. We had an ice storm when I was growing up and lost power for 3 days. Wood stove worked great as a backup, not much else would have.

hedora 4y ago

Dual source heatpump + Solar + battery + propane generator might be OK. The batteries would need to somehow be kept warm though. (The solar and battery are there to stretch out the propane supply until the delivery truck gets past whatever road blockages exist, and then addresses the inevitable shortage cause by the electricity going out.) Of course, an 80% efficient wood stove costs a small fraction as much as the above setup, and is more reliable.

flyingfences 4y ago
> The batteries would need to somehow be kept warm though. If I were buying such a setup, I'd just put the batteries in the basement. Plenty of space, and it stays 40-50°ish year-round here.
- adql 4y ago
  Not that many homes are built with basements nowadays. Water to water heat pump with pipes being directly under building's basement might've been pretty neat solution tbh, if you're digging for basement anyway might as well put some piping there for the heat pump
  - pfdietz 4y ago
    (Googles) I didn't realize basements were falling out of favor. Interesting!
Scoundreller 4y ago
Too bad few backup generators have the capability of dumping their heat output into the home via coolant loops or exhaust heat capture.
- dsfyu404ed 4y ago
  Because the residential ones are mostly small enough to be air cooled. Exhaust heat is fine in theory but HN would be screaming bloody murder if even one person died from CO as a result of a shoddy install or cracked heat exchanger so it's basically a nonstarter if you're a big juicy lawsuit target like a business. While there's nothing fundamentally different from a forced hot air furnace the novelty factor makes fending off the ambulance chasers more expensive than it's worth.
  - hedgehog 4y ago
    The way to do it is probably to colocate the generator with the condenser unit and use a thermostat-controlled second loop to move heat to/from the main refrigerant loop as needed. This gives some options to keep the generator from getting too cold to start as well as recover waste heat when it's up to temperature.
whazor 4y ago
Heatpump also needs to be kept warm, but those pumps do that themselves.
falcolas 4y ago
Given the need to maintain a ~100°F temperature differential on at least 6 days so far this year (at least here in Montana), a solar-augmented generator is probably not enough. Our heat pump has a natural gas backup, and even it was running at about a 60-70% duty cycle on those days. All that to say: +1 on a wood stove backup.
aidenn0 4y ago
Starting a generator below a certain temperature becomes hard too (most lubricants do a nice impression of putty when sufficiently cooled). As an aside, if you have a large free-standing propane tank you probably don't need to worry about stretching out the supply. I've known people who use propane as their primary heat source and can go a month between deliveries. Even assuming your propane heater + heat pump is 1/3 as efficient, that should give you 10 days of heat.

throwaway894345 4y ago

Why wouldn't a gas furnace have worked?

flyingfences 4y ago
Gas/Oil Furnaces/Boilers still need electricity to run the blower (air into the firebox) and circulator (hot air/water from the unit to the rooms) motors.
smiley1437 4y ago
FWIW older gas water heaters that use a standing pilot flame and piezoelectric ignition can run without electricity. Combustion products are vented passively by convection. With this type, as long as you've got gas, you can have hot water. Maybe huddle by the hot water tank? For the sake of efficiency, most newer gas water heaters need electricity for ignition as well as to power the fan that exhaust gases. All gas furnaces will need electricity to run the fans.

hirundo 4y ago

The woodstove is my primary heat source, it isn't modern, and it works regardless of the weather. But it isn't difficult to image circumstances where it fails, since it almost happened to me. I had a gout attack that made it very painful to bring in firewood. If I had central heat it would have been a matter of flipping a switch on the thermostat. Instead it got so cold that I just suffered the pain, like walking on a broken foot. After that I got my central heat fixed. It's nice to have both options.

sgent 4y ago

For a backup wouldn't a gas baseboard heater or room heater work? I know they are not in favor due to fire and CO issues, but for an emergency backup they worked well enough for our parents and grandparents.