RV panels connecting to grid tie

[BigReginaRick]

I am wanting to upgrade my pop up trailer solar system to 400W. I have a pretty good understanding how to do that. However, since it will be parked on the south side of my house while not camping I am interested in connecting to my grid power with most likely an Enphase micro inverter. Undecided if I would have dedicated solar panels at my house as electricity is cheap here in British Columbia (.116/kWh) and all from hydro. But I figure since I will have solar on the RV for off grid camping might as well try to utilize them while it is parked at home. Anyone have experience with this type of thing?
flipside would be suggestions on how to use rv solar system power while at home to power certain household electronic.

 

[Bill Taylor]

It can certainly be done, but the return on investment would probably not be worth it. And forget any illusions of being code compliant. The simplest solution would be to run an AC line from the RV into one room of the house. Use a power strip and plug the computer or television into it. That way at least you'll be able to get some use out of it at minimal cost

 

[svetz]

Welcome to the forums!

While you can power home devices off it... don't plug it into a wall socket, that's bad for two reasons:

1. It might void your home insurance.
2. Power meters run forward with amps regardless of direction... so you'd end up paying for the power you use and the power you export. You need a net-meter for it to work properly.

It might also not be expensive to be code compliant. Where I live it was free to have the power company install a net-meter and get the system approved. I did a full system with a building permit, which is nice as engineers review the plans to ensure they meet code which generally means there won't be insurance problems.

I'm not familiar with the code compliance in BC, but don't see why it wouldn't be possible, something like this:

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It would also allow you to have power in the RV when the solar was out.

Enphase?
Enphase is a very non-typical choice for an RV as they (like any grid-tied inverter) won't work without the grid being on (or having an AC coupled solution such as Ensemble (possibly IQ8s) or Tesla powerwall). Typically for an RV you'll see a small string inverter. But, if you want to hook it to your house, it can't be any old inverter... it'll need to be a hybrid-inverter so it works both with a battery and the grid (the inverter's output needs to match/synchronize to the phase/frequency of the grid).

 

[chrisski]

I think Bill was actually suggesting an extension cord To power devices and not plugging back into the grid that way.

If you could produce 4 kWh of electricity a day, you’d save about 60 cents a day. More likely, its around 1 Kwh a day on average Or abut 15 cents a day. I don’t really see how to practically connect this and become ahead. Not only with the cost of the equipment, but permitting.

Maybe an LED strip powered by the RV that goes on the porch or around the garden, or some other circuit separate from the house would be more practical.

 

[svetz]

Nice economical analysis! But it still adds up. At 15¢ per day, that's $0.15 x 350 d/yr (assuming 15 days for camping ;-) or about $52/yr. If he already has an RV outlet on the house for RV power it's possibly no cost (oops... yeah, add in the cost of a hybrid inverter over a standard inverter and it probably won't pay for itself over the life of the RV).

I think Bill was actually suggesting an extension cord To power devices and not plugging back into the grid that way.

My bad! Thanks for the correction! That'll learn me to post before coffee... apologies Bill Taylor

 

[chrisski]

I think where it may not add up is with battery replacement.

The true cost of battery replacement after five years will probably be closer to 50 cents a KWH, so cheaper to run with house power....Unless, those batteries would last just as long, which as I look at my Trojan charge, if is not a huge drain, probably would end up replacing them at the same time.