Thanks for your thoughts, and I also like to think about it this stuff!
Please note that this is at a vacation home we use frequently year round. Additional detail:
Too cold means cold enough to damage plumbing. In the Upper Midwest, the common pattern is that after a severe snowstorm (which is the primary cause of electrical outages), the temperature plunges, often to well below 0 degree F. PEX is usually fine, but copper and especially fixtures are vulnerable to cracking. We do not drain the pipes when we leave, and if we did, we would go much less often. Also, we frequently have others use our place, and would not count on them to do so.
The primary heating system is electric geothermal. There are four active zones in winter, two radiant floor heat and two forced air zones. All are normally powered by electricity. It is a fairly large system with over 1000ft of buried heat transfer pipe in several wells.
We have two devices that consume propane. One is the standby generator, the other is a fireplace. The whole geothermal system can be operated via the generator, but the efficiency of the internal combustion engine plus the losses in electricity production means less than 25% of the energy in the propane is converted to electricity. On the other hand, the fireplace is more like 65-70% efficient. So, in an outage, I have the fireplace take over heat production in one zone, using the blower to recirculate for that portion of the house. The rest runs on generator. There is no practical additional backup. A battery system would buy some time, but the generator is relialble and self tests frequently, so that seems like marginal benefit at best. We do have a nice south facing roof plane, but it is shaded by a 200+ old pine tree that is not going anywhere. Also, based on my experience at home, solar production in the winter in this part of the country is pretty meager.
So, to get back to the home energy meter, I want to do the following automatically:
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Detect that the generator is operating by using the meter to detect current from the generator flowing into the transfer switch.
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Use Rule Machine to change thermostat settings in the forced air zone with a fireplace to make the fireplace the primary heat source, while using the inefficient generator electricity production for the rest of the house.
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Revert the thermostat settings after power is restored.
The only tricky part is detecting the generator operating. I get a notification from the generator’s app, so I can do all of 2 and 3 above manually, but what fun is that? And I would like it to work if the internet service is out due to a storm
Hope this is interesting. I would be very interested in alternative ways to detect the generator operating.
Thanks!