Grid Tie Inverter

The point I was waiting for someone to bring up is on the OP's fifth wheeler, how or where is he going to have enough solar power to ever make this a worthwhile endeavor? He might get 1500W of solar up there if he tried real hard, but after his usage, how is there going be any meaningful amount of power to return to the grid?

Bill

the OP asked about powering From Battery

I am thinking about using a Grid Tie Inverter in my 5th Wheel. Can I use a Battery for input Power, or would I need Solar?

nobody is going to BUY a Grid Tie inverter to use Battery Power to feed the Utility lines

i suspect he has access to one for No charge, and thought maybe he could use it, instead of buying PSW inverter

i don't see how he could think he could reduce his electric bill using battery power to feed the grid

For a low power system as such(my above link) I don't think a permit or anything else is required. The system still shuts off if grid becomes unstable or goes off line. Assuming draw is well above the rating all power will be consumed and just reduce what is pulled from the pedestal.

Old gear meter would just run backward and as long as it moves forward for the month all is fine.

Some electronic meters count all power as usage no matter which way the electrons flow. Not great but if consumption continuously exceeds the panel it will not matter.

says it can produce 400 kWh per year. That is $40 annual savings at 10 cents, $80 savings at 20 cents. So 10 year payback if used fulltime in the southwest at 20 cents per kWh. Not a great value IMO.

I guess the number of years depends on how many days a year he is grid-tied. With vacation-like scenario, 30-40 days a year, I wouldn't bother.

Oops, I made a couple of bad assumptions. If you're parked in the same place over an extended time you could set up a backfeed/net metering system. The final cost varies wildly from state-to-state because of different incentives. As an example, I have one battery backed system and one non-battery system, and I expect each to hit breakeven in about 20 years from when it became operational. Whatever you full-time breakeven time is, it will be lengthened proportionately buy the amount of time you're away from your backfeed site.

If using this to reduce electric bills you will need to have a net metering agreement with the power company. You will need to have a meter installed that runs both ways. You will likely be required to install a disconnect switch by the meter for the power companies access. You will need the installation to be permitted and inspected by the city or county it's installed in.
If you can do all this then you can probably install a grid tie inverter and reduce your power bill. You won't need a battery.
If you want to integrate this with a battery based inverter there are several models available made by Conext and Outback. None of them are 12v DC. They are all 48v DC. You can install a 48v battery bank, 48v solar array, and 48v grid tie capable battery inverter. It will reduce your electric bills and provide off grid power when not connected to the grid. It will take around 15 years to recoup the investment. Yes, really. Grid tie only takes around 8 or 9 years. It's cheaper not having the batteries.

It's an interesting product, SMK.

I only think that 250W @$800 will take forever to return the investment. It will collect 20-30 KWH a month, at best. With less than full-time use it doesn't look too enticing. Unless the rates in his area are abnormally high. Metered RV parks "could" fall in this latter category :)...

The numbers are better when comparing solar to generator though.

250W is a monster, it has to be mounted permanently.

Maybe something like this:

http://www.pluggedsolar.com/

I think you want the 250w system. Maybe two.

Clay L wrote:
That type of inverter seems to be overkill for your 5 Th wheel. It appears to be meant to tie into and synchronize with the power grid. Do you want to use it because you have one available?

I was thinking of using one to reduce electric bills.

For a grid-tie you need a solar. A big one, 2,000W or larger. There isn't much sense spending money on a grid-tie inverter if you don't have spare energy to put in the grid.

Battery you can use as a back-up when there is no grid.

Paperwork will probably be account-specific, like for a certain seasonal park.