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Old 03-23-20, 07:30 PM   #5
MN Renovator
Less usage=Cheaper bills
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I agree that 3 solar panels in series would get you to the terminal voltage you are looking to supply to the charge controllers. 5kw system is a bigger system than what I have on my house which will be excellent to have grid-tied once you are able to.

I couldn't find the latest Ah spec on the batteries you bought, but it seems that they used to advertised with a 105Ah spec. You wouldn't want to pull more than half of that from them if you want them to have a reasonable lifetime(relative to any other lead acid battery). your 48v system will have about 2.5kwh usable capacity, which would be replenished very quickly with reasonable sunlight if the power usage isn't high at the same time but if it's not sunny they will drain down very quickly depending on your power usage. If you don't have much power usage when the sun isn't out you might make it to the next day if you keep the power usage minimal such as a refrigerator, meager use of LED/CFL lighting, a furnace blower running only when it's heating, not leaving computers/appliances on overnight. These batteries wouldn't run electric strip heat, a heat pump, or an air conditioner. ..although depending on the power usage of an air conditioner, your system might be able to run a small 120 volt window air conditioner if the batteries are full when it tries to start and the inverter can handle the motor starting load. I disagree with jjackstone and I run inverters with motor loads as long as the inverter is able to start the motor, some don't handle inductive loads well and they shut down or the motor doesn't run properly unless there is enough of a resistive load to balance out the negative properties of the inductive load. Since you have a 5000 watt continuous inverter, it would likely have no issues starting up most appliance loads.

Your inverter choice is a 120 volt unit which means you won't be able to run any 240v appliances or connect it to your house service panel unless you use a transfer switch designed for 120 volt generators and have it switch power to one or a few circuits in the panel. ..again not sure on what you are planning to power with this system in the off-grid configuration

You said this was for a prep situation, I personally plan for not having available electricity and have a gas generator to run my furnace to keep my pipes from freezing in the winter which means with moderately cold weather like we have now. I wouldn't bother, I'd just put on a sweater, coat, jeans, and thermals. I might run the fridge until I can get eat enough food until I can get a cooler filled with ice and then I'd eat the food ASAP. In the winter, the cooler goes outside or in the garage to preserve the ice, in the summer the cooler stays in the basement where it's coolest.
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