Getting Solar Power INTO the House so I can use it

KnowledgeSponge
KnowledgeSponge Solar Expert Posts: 173 ✭✭✭
Ok, so I've got solar panels, a charge controller (albeit an entry level one), an Inverter and Batteries.

But I STILL don't really know how to get the power into the house and distributed to appliances and lights.
OTHER than plug a multi-outles trip into the Inverter and then run extension cords to any appliance I might want to run.
But I want to run regular house lights and outlets off this Solar Power without running extension cords everywhere.

I guess this thread could be simplified to....

I have Batteries and an Inverter.
How do I get power from a batteries connected to an Inverted distributed to my house wiring so I can use Solar as backup power
or alternate power?

I imagine I need a separate panel.
I DO have a Generator Manual Transfer Switch already and thought that would make this all super easy.
In another thread, I tried to use my EXISTING generator transfer switch to link my Inverter into the House wiring and I think eventually I'll achieve that.
But it's going to take a lot of work to ensure the proper connections so I don't damage my inverter.

But what if that never works?

What's the best way to Integrate Solar power as a backup power source and conveniently link that power to the existing house wiring
so that I can feed selective circuits in the house with the Solar power when I choose to?

Is there a way to utilize my existing Generator Transfer switch?
Or do I need a different kind of sub panel / transfer switch / Inverter?

Comments

  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: Getting Solar Power INTO the House so I can use it

    I think the biggest issue is, will your inverter happily coexist with the grid? Some don't like it. I don't remember the details on yours.

    The best / easiest way to me is to purchase an inverter intended for that purpose. I have an Outback inverter with built-in transfer switch. I installed a small breaker panel beside my home's main panel and pulled the desired "backed up" circuits off of the main panel and connected to the subpanel. Feed the inverter with a larger breaker in the main panel. Now I can tell the inverter to switch between grid and battery, and it Just Happens. If grid power fails, I usually don't even know it - the first I know about it is when I notice my microwave (not on the inverter) needs to have its clock set!

    There shouldn't be any reason your separate components can't work, long as they're designed for it. I don't remember all the details about your kit, so can't say specifically. If I'm remembering the right panel, your transfer switch was the one with a bunch of separate grid-off-gen switches, designed to wire into each circuit separately. That would work, but as you said lots of wiring. I prefer the cleaner arrangement of moving those loads off to a subpanel and having a single feed / transfer switch that feeds the entire panel.

    Edit:
    I will add - this is NOT how I first used my system! At first I actually ran a couple dedicated circuits that were completely isolated from the grid panel. Had an outlet in the garage by the furnace, one in the kitchen by the fridge, one in the back bedroom which is my office. If I wanted something to be "off grid" I had to plug into one of those outlets. I *really* didn't want to run a bunch of redundant wire down the walls of other rooms, so eventually went with the sub panel and picked off existing circuits.
  • verdigo
    verdigo Solar Expert Posts: 428 ✭✭
    Re: Getting Solar Power INTO the House so I can use it

    This is a good noob question that I will be watching closely. I had intended to do the same thing with a generator transfer switch panel but I would have had problems with 240 volt loads. I need to replace the house A/C distribution box anyway as it has an old Square D unit that it's 100 amp main has failed. I am currently back feeding a 100 amp breaker to power the house with. It would be nice to do this all at once with a sub panel to enable switching from grid to solar. Examples with schematics would be way cool.

    Dennis
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Getting Solar Power INTO the House so I can use it

    It is really better to back up a moment and say what it is you want to do.... Power an entire home, or just fridge/freezer, a few lights, and charge the laptop+cell phones.

    Then, how you will do that in the home... Add new wiring for backup only circuits or you want to switch circuits from grid to backup power? Do you want this automatic? Do you want inverter + backup genset, etc...

    How long do you want to power those loads (days->generator; weeks generator or solar, months+ -> full solar system). Do you have Net Metering from your power company available, etc...

    Want to start small and grow? It is very difficult to "grow" a solar system or generator... Generally, major components have to be replaced (resold on EBay, etc.) if you more than double the storage/output power support, etc...

    KnowledgeSponge's system would work--The only confusion (I have) is the AC Inverter he is using (Xantrex 2,000 Watt--probably TSW, but not clear or in manual, and nothing about neutral/earth grounding). Requires enough electrical knowledge to pull the GFI outlets, figure out if there is a neutral+earth bond in the inverter, and if it is even a TSW type inverter. Are there other issues--I really don't know. That is the problem when the "wrong" device is picked for the job. It was not designed for this use (it appears) and therefore it is unknown what you will trip across when trying to implement the system.

    A "simple" per load transfer switch (sub panel where circuits are brought from the main panel to the sub panel) and use a A/off/B transfer switch on a per 120 volt leg basis with a 120/240 VAC split phase plug (for connection to genset and/or AC inverter) will work pretty well. It requires manual intervention to manage loads--And could be setup to supply backup AC inverter power with the "right" AC inverter and transfer switch setup--But this all piles complexity/options on top of the base wiring requirements.

    Unfortunately, there is no "simple" way of doing this. K.S.'s way is the "less expensive" method, but has lots of frustrations.

    Could simply toss in a Schneider/Xantrex XW/Context Hybrid AC inverter + sub panel and have a really nice whole house UPS (uninterruptable power supply) system with a large battery bank... But this is not cheap, and requires a fair amount of knowledge to get a cost effective/reliable backup autostart generator.

    Take a look at 2manytoyz's website... A really nice history of where he started and how it grew--Then knowing now what he knows, starting over from scratch (using most of the exiting equipment) to reconfigure into a clean(er) install:
    You don't know what you don't know until you try... Hopefully, the damage and injuries from such learning is kept to a minimum.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • KnowledgeSponge
    KnowledgeSponge Solar Expert Posts: 173 ✭✭✭
    Re: Getting Solar Power INTO the House so I can use it

    Excellent replies. Thanks.

    Well, as mentioned, I already have a working Manual Transfer Switch that I can plug my generator into and it works perfectly to power those circuits in my home that I pre-selected
    to power up based on usefulness during outages and amperage limitations. That system is working perfectly.

    For some reason, the Inverter's 120v output does not work properly when connected to the Manual Transfer Switch.

    Ideally, I would simply create a cord with a 5-15P male plug (common household plug) on one end and a L14-30R 4 prong female
    plug on the other side and simply plug this cord into the Inverter and into the Manual Transfer Switch and that would work.

    Unfortunately, it's not that simple. First of all, the Inverter output is limited to 15A.
    Not much available power. So I think I need a different type of Inverter. One that can supply more amps.
    Second, I think I need an Inverter that is wired to utilize a L14-30R female plug or at least have two 120v hots, a neutral and a ground so I can add a L14-30R plug to it that will fit my Manual Transfer Switch.

    I do NOT want to grid tie. I will never want to feed excess power back to the utility company.

    I need to read up on the Outback Inverters. Maybe I need one of those with the built in Transfer Switch.

    But I STILL want to keep my generator Manual Transfer Switch. So my setup could get VERY complex.

    Oh well, this issue us not going away. I will study, plan and "purchase" until I get what I want.
    I think I'll look into Outback Inverters now.
    Stay tuned.
  • KnowledgeSponge
    KnowledgeSponge Solar Expert Posts: 173 ✭✭✭
    Re: Getting Solar Power INTO the House so I can use it

    At a glance

    Looks like I will need to spend at least $1,600.00 to get an outback Inverter

    Doable, but will take some creative diversion of funds and some doing without other things....and some time.

    Then again, purchasing one of these is a MAJOR expense and moves the endeavor from "Hobby" to something more serious.

    Not totally sure I want to get that deep into this hobby yet.

    It would take a LONG time to recoup these types of investments. And I'm not off grid at this time.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Getting Solar Power INTO the House so I can use it

    You have two choices: utilize the existing AC distribution in some way or create a new one.
    Using the existing system, even with imposed power limitations, is likely simpler and cheaper.

    We've already discussed connecting to the generator input of your transfer switch in another thread. If it does need 240 VAC to activate then you either need to feed your 2kW inverter through a transformer to step up the Voltage (and likely overload the inverter with high Wattage 240 V loads) or get an inverter which outputs 240 VAC native like this Magnum: http://www.solar-electric.com/maenms4040wa1.html The Outback FX series do not output 240 VAC. Nor are you likely to find an inverter with a 240 Volt outlet on it: these will all be hard-wire designs.

    You might benefit from picking up a book on standard household wiring and reading it thoroughly until you become more at ease with 240/120 and its peculiarities. You are right to be cautious; it is dangerous and can kill you or burn your house down. A few precautions can reduce the risks, but never eliminate them. Better safe than sorry.
  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: Getting Solar Power INTO the House so I can use it
    I need to read up on the Outback Inverters. Maybe I need one of those with the built in Transfer Switch.

    But I STILL want to keep my generator Manual Transfer Switch. So my setup could get VERY complex.

    I presume you're saying you want to be able to optionally use the generator and/or inverter and/or grid. I do that too.

    In my case, since the Outback only has a single grid input, I bought a "On-Off-On" disconnect - instead of the usual on/off disconnect, "Off" is in the center, handle-up is connected to one set of lugs, handle-down to another. I tied one set to the breaker in my grid panel and the other to a socket on the back porch that I plug my generator into. Anytime I want to test the generator, or if the grid is down for an extended time (hasn't happened since I set all this up, of course!) I just flip the Big Switch down to "Generator" and fire it up. The Outback inverter just sees it as grid power input and acts accordingly. Of course I'm using an EU2000i, so have to be sure to limit charge amps if I want to use the built-in charger.

    Or you could pick a different inverter with two grid inputs. I know Xantrex does that, not sure about others. Hook grid to "Grid 1" and generator to "Grid 2" (or however they're marked) and let the inverter sort it all out. You could even set up the generator permanently, wire a start relay to the inverter, and let it fire the generator up automatically if needed.

    The main issue I see with your particular generator transfer switch is that it's intended to provide a separate Gen-off-Grid switch for each circuit. A fine idea, but a LOT of wiring!
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: Getting Solar Power INTO the House so I can use it

    There're two kinds of hobbies.

    Hobby to learn. Tou can connect the inverter to this existing transfer switch. Learn about AC electriity. Learn sbout one-phase 240V electric distribution used in the US. Once you know this stuff, it won't be hard to connect the inverter.

    Hobby to spend money on. You're looking for a new big 240V hybrid inverter. It'll work great and will have all kinds of connnections. There are several big brands to choose from. Think at least $2-3K. But it's still much cheaper than collecting Ferraries.