Hi all, I'm just reading up on solar to set up an off grid system for my house.. Dump loads seem needlessly complicated though!

[Boomzilla]

I'm pretty decent at wiring, electric, and tinkering in general, and I used to be an industrial battery equipment tech so I've got the basics of that end of the system down at least.

I'm planning a system that will keep the essentials of the house running. It will run separate and parallel with the existing wiring and I'll utilize colored receptacles to identify battery power. I don't want to backfeed my panel because I'd like to use the PV energy as much as reasonable even when we have ongrid power.

I know I could install a manual transfer switch and even have one lying around but honestly I just don't like them. The wiring inside those things looks like junk.

I'm still trying to understand how best to run a dump load to a water pre-heater. I can easily hook up a relay controlled by voltage but I don't want it to short cycle or keep the batteries from fully equalizing, but I also want it to be as efficient at using that 'extra' energy as possible. I can't believe I don't have more options for a SCC with diversion load built in!

Anyway, I'll keep reading up on it and I'm sure there's a good solution for me.

 

[DThames]

"I don't want to backfeed my panel because I'd like to use the PV energy as much as reasonable even when we have ongrid power." Sorry but that statement doesn't really make sense. If you put power to the grid, that is the ideal load to fully use all available potential. At any moment, what you make will be used inside your house with the excess being sent to the grid. So that is not a reason to avoid grid tie/backfeed.

If you get pay a fee or a exchange cost to store on the grid, that is a reason to want to manage all you can locally. Sol-Ark inverters have dump load options.

 

[Boomzilla]

"I don't want to backfeed my panel because I'd like to use the PV energy as much as reasonable even when we have ongrid power." Sorry but that statement doesn't really make sense. If you put power to the grid, that is the ideal load to fully use all available potential. At any moment, what you make will be used inside your house with the excess being sent to the grid. So that is not a reason to avoid grid tie/backfeed.

If you get pay a fee or a exchange cost to store on the grid, that is a reason to want to manage all you can locally. Sol-Ark inverters have dump load options.

I understand that 'selling' to the grid would utilize the output. There are many downsides to that connection and honestly I don't want anything to do with it. I want a system that works as a backup for my essential needs and remains completely separate from the grid. I was talking about backfeeding the panel in the same manor you would with a gas generator.. open the main breaker, close the generator "main" and now your house is being fed by the generator. I want to dump any excess power into an electric water heater plumbed directly before my main water heater.

 

[DThames]

Many All In One (AIO) inverters will blend solar, battery, and grid power to power home loads. They have different modes that can be programmed. The typical setup is to move critical loads to the output side of the inverter. In UPS type mode, the grid power can just pass through the inverter to power the loads until you loose the grid and then the solar/battery power steps on. In a Solar/battery first mode, when you have solar power and battery conditions are met, solar power is blended with grid power to power those same loads. So as the sun power increases, the grid usage decreases. So on sunny days, you might reduce your grid power usage to almost nothing (while the sun is on the panels effectively). While not separate wired, this type of system uses solar fairly well.