Grid tie inverter + panel for now...batteries + more panels later?

[jeffm]

Hello all,
I've been wanting to try solar for a few years now and I may have finally reached my tipping point as far as cost and ease of DIY is concerned. I've been searching the web for the last hour or two looking for an example of what I'd like to do, but I may not know enough about the industry/products to find what I'm looking for. I was hoping I might run the idea I have in my head by the community and see what your thoughts are?

I'd love to start simple, a single panel (maybe something like this) and tie it in to my home with a grid tie inverter (like this). Is it really that simple? Would I need a charge controller? Is that single panel going to produce enough current that the grid tie inverter can do me (and my electricity bill) some good?

As a second phase I would love to have a battery backup solution for small things during blackouts. I know I can't rely on the grid tie inverter to fuel my house, as it shuts off during blackouts. In my head it seems I would:

1. have panel(s) producing power
2. connect panels to a charge controller, one where excess power can be directed to an "overflow" circuit (???)
3. power needed to keep battery(s) charged goes to battery(s)
4. excess power could be directed to the grid tie inverter
5. could connect a standard DC to AC inverter on the batteries to power small devices during a blackout

Is that a realistic model for a simple battery backup solution? If so, I'm having a hard time finding a flavor of charge controller that handles overflow...perhaps I don't know what I'm looking for, its technical name or maybe it doesn't exist?

Any and all comments or opinions would be appreciated, even if its just a pointer to a post where this has been discussed before...I'm sure I'm not the first to try going down this path

Thanks in advance,
Jeff

[Naptown]

No you are not the first.
Excuse the short reply I need to find a popcorn eating smilie

[inetdog]

Hello all,
I've been wanting to try solar for a few years now and I may have finally reached my tipping point as far as cost and ease of DIY is concerned. I've been searching the web for the last hour or two looking for an example of what I'd like to do, but I may not know enough about the industry/products to find what I'm looking for. I was hoping I might run the idea I have in my head by the community and see what your thoughts are?

I'd love to start simple, a single panel (maybe something like this) and tie it in to my home with a grid tie inverter (like this). Is it really that simple? Would I need a charge controller? Is that single panel going to produce enough current that the grid tie inverter can do me (and my electricity bill) some good?

As a second phase I would love to have a battery backup solution for small things during blackouts. I know I can't rely on the grid tie inverter to fuel my house, as it shuts off during blackouts. In my head it seems I would:

1. have panel(s) producing power
2. connect panels to a charge controller, one where excess power can be directed to an "overflow" circuit (???)
3. power needed to keep battery(s) charged goes to battery(s)
4. excess power could be directed to the grid tie inverter
5. could connect a standard DC to AC inverter on the batteries to power small devices during a blackout

Is that a realistic model for a simple battery backup solution? If so, I'm having a hard time finding a flavor of charge controller that handles overflow...perhaps I don't know what I'm looking for, its technical name or maybe it doesn't exist?

Any and all comments or opinions would be appreciated, even if its just a pointer to a post where this has been discussed before...I'm sure I'm not the first to try going down this path

Thanks in advance,
Jeff

End of the trailers, and now the feature file begins. I hope Naptown is back already with his popcorn.

1. The 100 watt panel for $219 is more than $2 per watt. You can get higher power panels for under $1 per watt.
2. You can get CCs that will divert excess panel power to a separate load, but none that will allow you to easily send that power to a GTI.
3. The GTI you linked to, like all plug-in and pray GTIs currently advertised, is not UL-listed and is not legal for connection to the Grid in the US or most other countries.
4. For the amount of power you will get from that panel (if you are lucky maybe 500 watt-hours per day, and after the GTI losses maybe 250 watt-hours) will save you a whopping $.03 per day if you pay $.12 per kWh from the power company (POCO.)
5. If you need a simple battery backed inverter for short (less than a couple of days) power failure, just a simple AC powered battery charger to float charge your batteries whenever the grid is on will cost a heck of a lot less. For longer outages, the same battery and charger plus a small quiet generator.
6. Even when you get into large expensive systems, the economics of solar charged backup power just do not make sense for most people. Grid tie with a legal installation does make sense if you have incentives and a high POCO price per kWh.

[solarside]

I just googled using "when the batteries are fully charged gti" (without the quotes), there's two videos and a few products you can buy that do what you want with the combo GTI and batteries.

A 300W GTI will be about 21A at it's max input. About 15A if you run it off a 24V battery bank with a controller device.

Like you, I want to get away from the power company but sometimes you have to do that in small steps, a small low cost grid tie is a good way to get a start and lots of people have done that successfully in videos on youtube and for many years, do a search there for "grid tie" and see what you can find.

The GTI and batteries combo puts you in a perfect situation for power outages, keeping the batteries charged and lowering your power bill a little when the panels are not charging the batteries. A couple of 100 Ah batteries will give you enough power to put you in a good position when the power goes out, unlike everyone else who are not prepared.

[Sunking]

I just googled using "when the batteries are fully charged gti" (without the quotes), there's two videos and a few products you can buy that do what you want with the combo GTI and batteries.

A 300W GTI will be about 21A at it's max input. About 15A if you run it off a 24V battery bank with a controller device.

Like you, I want to get away from the power company but sometimes you have to do that in small steps, a small low cost grid tie is a good way to get a start and lots of people have done that successfully in videos on youtube and for many years, do a search there for "grid tie" and see what you can find.

The GTI and batteries combo puts you in a perfect situation for power outages, keeping the batteries charged and lowering your power bill a little when the panels are not charging the batteries. A couple of 100 Ah batteries will give you enough power to put you in a good position when the power goes out, unlike everyone else who are not prepared.

ROFL. You have no idea what you are talking about.

[russ]

I just googled using "when the batteries are fully charged gti" .

We usually say search is your friend but should add that you need to have an idea of what you are looking at.

There is far more BS on the net than good information - you are finding total BS and believing it - worse you seem to be trying to convince others.