Can I use my house as a battery?

[Nsmith0723]

At the risk of coming of as ignorant here goes. I have 6 250w 36v panels that will be 3s2p for 108v at 14a. I have a all in one growatt 3kw 48v all in one charge controller/inverter. I have a diy lifepo4 48v 16s 78ah with a 100a overkill bms. Which I think will be under sized for the application and will have to switch to grid before daybreak. I originally planned to run my fairly old chest freezer and furnace blower motor. First on the list is upgrading the freezer. I was thinking though, do I even need to run them at night in the first place. The house for seems to hold its temperature well. I'm thinking say its winter and you heat it up to like 75f during the day and let it cool down at night with a smart thermostat. Really cold temperatures like -20 I'm sure the furnace would have to kick in before daytime, but most of the time I would think this would work wouldn't it? It normally takes a couple days for the house to cool off significantly when we loose power, which is the whole point of the system. For that matter the freezer stays froze for over a day.
TLDR I don't need to heat my house or run my freezer at night for the most part

 

[mrzed001]

At the risk of coming of as ignorant here goes. I have 6 250w 36v panels that will be 3s2p for 108v at 14a. I have a all in one growatt 3kw 48v all in one charge controller/inverter. I have a diy lifepo4 48v 16s 78ah with a 100a overkill bms. Which I think will be under sized for the application and will have to switch to grid before daybreak. I originally planned to run my fairly old chest freezer and furnace blower motor. First on the list is upgrading the freezer. I was thinking though, do I even need to run them at night in the first place. The house for seems to hold its temperature well. I'm thinking say its winter and you heat it up to like 75f during the day and let it cool down at night with a smart thermostat. Really cold temperatures like -20 I'm sure the furnace would have to kick in before daytime, but most of the time I would think this would work wouldn't it? It normally takes a couple days for the house to cool off significantly when we loose power, which is the whole point of the system. For that matter the freezer stays froze for over a day.
TLDR I don't need to heat my house or run my freezer at night for the most part

You have a 3,9 kWh battery and a 1500W solar panel. Lets say with 5 hour it produces 7,5 kWh
You can not store so much in the battery. But you can use it. It you have an inverter AC then you can heat/cool your house while sun is up (with scop 5 you get 5 times the heat as you could get with a simple electric heater or by heating water and circulate it).
The 3,9 kWh is good for lets say 16 hour x 240W constant usage. It will be more than enough for your freezer and furnace blower I think.
But best to measure first how many Wh they use in a day.

 

[time2roll]

Yes all that works. No need for a "smart" thermostat to second guess what you want.... most are programmable to adjust at specific times and temp day and night. Most have four changes each day. Some are same all week, some have 5/2 for weekday vs weekend, others can have 7 day programming. I use mine to primarily run the A/C mostly at night on low cost electricity and minimum during peak hours.

Can use a simple timer on the freezer to mostly avoid overnight drain on the battery. Watch the temperature as it may creep up 1 or 2 degrees per day if not given enough run time.

 

[Nsmith0723]

You have a 3,9 kWh battery and a 1500W solar panel. Lets say with 5 hour it produces 7,5 kWh
You can not store so much in the battery. But you can use it. It you have an inverter AC then you can heat/cool your house while sun is up (with scop 5 you get 5 times the heat as you could get with a simple electric heater or by heating water and circulate it).
The 3,9 kWh is good for lets say 16 hour x 240W constant usage. It will be more than enough for your freezer and furnace blower I think.
But best to measure first how many Wh they use in a day.

Huh, I was thinking it was undersized. Everyone seems to like the 100ah cells or even 280ah, they where out of the budget, I cheaped out. My house is currently propane heat and the ac isnt on the solar either. I'll have to check and see if they charge more at peak hours. Thanks!