Hybrid system design

[Coperdawg]

I bought a Nature power 1800 solar system with 2 extra Battery's because it was on special but had not done my research I also have 6 grape solar 100w panels that i am planning to use with a Sun 1000W Solar on Grid Tie Inverter with Power Limiter DC 22-65V to supplement by grid power usage.

The Nature power 1800 is basically three 12v 80Ah lead acid battery's each with built in solar chargers each connected to a 100w Panel (and connected in Parallel)

I would like to use the battery's at night connected to the Grid tie I think I can build some jumpers so that I can connect them in series or use a DC to DC converter to boost the voltage

Please recommend best way to achieve this, manual change over switch? etc.

Thanks in Advance for any recomendations

[littleharbor]

Coperdawg, welcome to the forum.
The Grid Tie Inverter with Power Limiter DC 22-65V you are talking about sounds like one of those types that plug into a wall receptacle. If so, these are not legal for use in the US.

Not meaning to bum out out on your first post. Just need to mention this.

[Sunking]

Never going to happen.

[citabria]

I also have a portable 1800W UPS with a built in modified Sine wave inverter...it will get you about 6 hours of use with a laptop computer consuming about 65W per hour, if I recall correctly.

Also, I think one rule of thumb for the 12 volt powered inverter is not exceed something like 400W. See the stickies in this forum.

Also, you are planning on 5 batteries? in parallel, good luck with that. Sorry that you may have mis-spent some money, do not tell the spouse or you will be sleeping in the dog house for a while...

[Coperdawg]

I realized after the fact that I bought an item not particularly suited to my needs but I would like to at least use some of the power generated by the 1800W unit which only has 3 80 Ah batteries.

My understanding is that it is best to exercise batteries rather than just keeping them charged.

My grid tie Inverter is the plug in type and on a dedicated outlet so in my understanding is OK by code but probably not got the correct certification to get power company's approval.

[SunEagle]

I realized after the fact that I bought an item not particularly suited to my needs but I would like to at least use some of the power generated by the 1800W unit which only has 3 80 Ah batteries.

My understanding is that it is best to exercise batteries rather than just keeping them charged.

My grid tie Inverter is the plug in type and on a dedicated outlet so in my understanding is OK by code but probably not got the correct certification to get power company's approval.

It depends on your local code.

Backfeeding even a "dedicated" outlet with a fake or non UL listed grid tie inverter may still be unacceptable to your POCO as well as your insurance company should anything happen to cause damage to your home.

[jflorey2]

My understanding is that it is best to exercise batteries rather than just keeping them charged.

It is best to float lead acid batteries rather than cycle them.

My grid tie Inverter is the plug in type and on a dedicated outlet so in my understanding is OK by code but probably not got the correct certification to get power company's approval.

Chinese grid tie inverters are not designed to transfer power from batteries to grid; they are designed to transfer power from solar to grid. They may seem to work but will generally underperform and may present safety problems. (And of course they're still not legal.)

[bcroe]

Basically none of that equipment is suited for your goals. Grid tie inverters won't run unless connected
to a grid, but that requires a permit and that limits you to approved equipment (not plug in). Power drawn
from batteries is far more expensive than grid power, and they require constant maintenance. Bruce Roe

[Coperdawg]

Thanks Guys, whilst I agree and understand posts I was hoping for some redneck suggestions rather than IEE

[Mike90250]

We can't condone setups that are illegal in the countries we post from, the lawyers would eat us alive. And if your place gets damaged or a lineman gets injured from an illegal grid tie, the lawyers are the only ones that win.