Want to Install a Solar System with a Standby Generator on my Home - How to get Started

[thompsdw]

I want to install a new system on a home we are moving into in several months. Here is what I would like to accomplish. I want to install a reasonably sized solar system on the roof and I do want some battery capability. I will install the panels myself as I have done before on houseboats, RV's, etc. I will have a roofer install the solar panel mounts. I can't tell you how many solar companies around my location (heavy snow area) have caused a roof to leak (mostly by missing the rafters).

I want the panels to charge the batteries and then I want the batteries to be first stop on an auto switch charge controller (I haven't decided yet if it needs to be connected to the utility, but I am guessing the answer to that is yes). Once the batteries are depleted, I want the standby generator to start, charge the batteries, and supply the home. Here is why I am looking for this - we loose power where I live quite a bit, but I don't want to pay for natural gas all night long when all I likely need is lights and receptacles. Maybe a central furnace fan for heat, but nothing more. We have had several outages at night and I am making noise and burning fuel all night long for a white noise machine and a furnace.

Is this even possible and are there resources that you could direct me toward to prevent a bunch of dumb questions here? I'm really just getting started on how to do all this and just want to start researching.

 

[time2roll]

Need to decide the general purpose. So far it looks like a limited power system for during an outage only. In addition only select circuits will be active during an outage. Probably need a transfer switch and sub panel to separate what the inverter will power. Most would use an all-in-one inverter with integrated solar input and transfer switch. Need to discover what size is needed and calculate how much battery. then how much solar is needed to power the loads and charge the battery. Need to decide on an auto or manual start generator. Also decide on a generator to just charge the battery or put power direct into the house. Do you need 240v/120v service or just 120v on the sub panel.

There will be more but this will get the project started and start looking at the size of components that are compatible with the goals.

There is a Resources tab at the top of the page to poke around a bit. Give yourself some time to lay out the system you want.

 

[Q-Dog]

First step is to figure out what loads you want to power from the battery, and for how long. That would be referred to as a "power audit." Once you have numbers, the rest is easy to figure out.

 

[quantum`]

One. Step. At. A. Time.

 

[thompsdw]

Maybe a different spin on this question. What I am trying to learn here is how a solar tied system interacts with a standby generator. I think if the tied system is battery less, then there really is no attachment. You are just selling back to the grid. If there are backup batteries, I guess that is where it gets more complex. The backup gen will be wired to feed the entire home. So I know I would need some kind of auto switching inverter/charger. But when the power goes off, I think the gen is going to come on.

Maybe the battery system when you have a backup gen is just a solution that won't work? That is what I am trying to determine. Is there some type of controller that would run a subpanel off the batteries until a certain voltage and then when that voltage is hit - turn on the gen and charge the batteries? Would the gen (or controller of some sort) then be smart enough to kill the gen when the power comes back on?

I know Generac makes a charge controller - maybe this is the smart device?

 

[time2roll]

Yes low battery voltage can trigger the generator to start. Many RVs come standard with such a feature.

 

[Q-Dog]

Yes, my battery backup system can trigger a generator to start when the battery gets low. But I don't have an auto start generator, only a small Honda suitcase generator for emergencies, that I mostly lend to my neighbor.

 

[quantum`]

Generac is a good choice.