So what is the general consensus on an all in one inverter/charger vs separating the two pieces of equipment? I'm look at adding a small solar backup, 5-6kw worth of battery and 1400w worth of panels, would I be best off buying going with something from MPP or buying pieces individually and building from there? I am new to solar but have been in the electrical and utility fields for about 10 years now. Thanks!
All in one vs separate inverter/charger for first system?
- Thread starter Bremraf
- Start date
Wiring cost and connections are more with discrete units. I have done both. If AC charging is planned, for sure AIO is the way to go....unless you get an inverter/charger like AIMs has. Mounting clutter is also something to consider. Of course, fixing failed components, or altering your end game plan is easier with discrete units.
If you make your plan to not just have backup but to use available solar to power daily critical loads, look at the AIO units that don't require a battery. They handle usage of available solar differently than those that do require a battery. Those without a battery converter PV to the high voltage DC to power the inverter's current load while those that do require a battery tend to power the inverter's high voltage from the low voltage DC side, which causes all available solar to be routed through the battery charger, down to battery voltage, then backup to high voltage DC for the inverter. Those sort of suck in a way because charger logic governs inverter usage of available solar.
If you make your plan to not just have backup but to use available solar to power daily critical loads, look at the AIO units that don't require a battery. They handle usage of available solar differently than those that do require a battery. Those without a battery converter PV to the high voltage DC to power the inverter's current load while those that do require a battery tend to power the inverter's high voltage from the low voltage DC side, which causes all available solar to be routed through the battery charger, down to battery voltage, then backup to high voltage DC for the inverter. Those sort of suck in a way because charger logic governs inverter usage of available solar.
Rednecktek
Solar Wizard
Well, sorry to be the one to say it, but "It Depends" is the general consensus.
If you're tinkering because you have stuff and want to Learn All The Things then a multi-component system is the way to go, especially as you grow and start tweaking your system to see what it can do.
On the other hand, if you just want to slap something together and have something that works that you never want to change an AIO is the cheaper way to go.
There are pro's and con's both ways, it really depends on what you're wanting out of the system.
Once you've decided that then you move on to the Power Audit and my standard blurb which will follow shortly.
If you're tinkering because you have stuff and want to Learn All The Things then a multi-component system is the way to go, especially as you grow and start tweaking your system to see what it can do.
On the other hand, if you just want to slap something together and have something that works that you never want to change an AIO is the cheaper way to go.
There are pro's and con's both ways, it really depends on what you're wanting out of the system.
Once you've decided that then you move on to the Power Audit and my standard blurb which will follow shortly.
Rednecktek
Solar Wizard
Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:
1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.
1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.
2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.
3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.
4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.
5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round ) and help figure out which parts and pieces you're going to want to get.
1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.
1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.
2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.
3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger.
Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.
5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round
) and help figure out which parts and pieces you're going to want to get.MichaelK
Solar Wizard
As general rule, the AiO units cluster more towards the low end of the price/quality zone, whereas the component units cluster towards the higher end. You get what you pay for. Cheaper units are cheaper for a reason. They are made with lower quality parts, less application margins, and have shorter warranties, fewer or no third-party certification.
OffGridInTheCity
Solar Wizard
Nothing wrong with all-in-one! When I started (4 yrs ago), these weren't so popular, available and so I have individual components for my home system and I'm good with it but later (year ago) I went with MPP Solar for my trailer as it's just simpler.
I'm off-grid with grid assist via ATSs (auto-switch to grid when solar is low) and since I have individual components I had to do my own UPS to allow sensitive circuits to run uninterrupted - e.g. computers, tv, even the K-Cup (with clock for on/off) - during the solar/grid switching a lot of days. The off-grid oriented all-in-ones have UPS built into their design - another simplification.
So if you're planning an off-grid system, I'd recommend an all-in-one and I've had good luck with MPP Solar.
BTW - MPP Solar, GroWatt let you expand/parallel output to increase overall AC output and PV input and can share a single battery bank - so it's not a dead end.
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Haha! I knew I would get the "depends" answer. I am looking for something efficient and somewhat simple. I work full time in the utility sector and have 6 kids plus a mini farm, so ease of use is important to me. I am thinking of this backup serving double duty to run my 2 chest freezers and garage fridge, therefore taking them off the grid, as well as providing some backup power and to have these units be capable of keeping food cold in the event of an outage. My total watts when all 3 are running is around 500, I have yet to time them in an hour to calculate total run time per day.
An AIO that can pass grid AC when solar/battery conditions are not to your liking and also run off the solar/battery when there is no grid, would seem to make sense to run your critical loads. They have internal switching and some are pretty flexible about their profiles. Others are less than ideal.
Quattrohead
Solar Wizard
AIO for your first love, she should be willing to do it all !!!
Then you will get addicted and want to start playing with all the pretty girls !!!
Then you will get addicted and want to start playing with all the pretty girls !!!
MichaelK
Solar Wizard
Let's throw out some numbers and see what can work for you. I'll make a few generalizations about the appliances you mention
2 chest freezers: 600Wh/day each or 1.2kWh total per day
1 standard refrigerator 20cuft: 1500Wh/day
lights, TV, Video game consoles: 1000Wh/day
inverter itself on 24/7: 700Wh/day (this varies a LOT. An MPP might be 2400Wh. A component inverter might be 700Wh)
Total 6100Wh per day. So, let's say you need to generate ~6kWh of power per day.
The second assumption I'll make is that your location is temperate, and you have 2.5sunhours in winter and 5.0sunhours in summer. A sunhour (or sh) is NOT the number of hours the sun is up.
So, planning on the worst day of the year, you'd need 6100Wh/2.5sh = 2440W of panels. In summer that might be only 1220Wh. So, if your power goes off in December, then the 1400W of panels you are planning on might not be enough.
Now, the battery. If your consumption is ~6kWh/d, then the 5-6kWh of battery you are planning on is NOT likely to be large enough. Assuming your power goes out in a December storm, and stays off for just two days, you'll need more than 12kWh of storage.
So, all in all, it looks like you'll need to at least double your original estimates to make a viable system that is not going to fail you. Keep in mind these are MY numbers, which might not be exactly the same as YOUR numbers, but I'd bet they are close.
I can mostly get behind your numbers. When I check a calculator for my sun hours you are right in there, peak summer is about 6 and lowest in winter just under 2. I am not as worried about running fridge and freezers during winter, those would be okay in their location(garage and lightly heated mudroom, well, lol in power outage unheated mudroom) during that time, and it would be used to power the fan blower on my woodburner to heat the house. Which is comparable to a box fan(120 ish watt startup and 70 watt running load). I have the roof space for as many panels as my budget would allow, and panels are cheap, battery storage isn't. I could see definitely needing to up my storage capacity, as well as the field, but that in turn makes the inverter, charge and everything else more expensive. I see the rabbit hole going far. Lol. I could switch the freezers back to grid power once the sun hours start to dwindle if need be.
MichaelK
Solar Wizard
OK, let's take an updated look at your numbers. Let's say you don't have to keep the frig/freezers all on 24/7; one at a time maybe instead. We could ratchet your usage down from 6kWh to 4kWh. Assuming you get the same blackout in December (likely?) when you are only getting 2sh of light, then you'd still need 2000W of solar. Very doable. If you want to keep things going for just 2 days, that's still 8kWh of storage. Assuming you only consume 75-80% of an LI battery, in the real-world that means 10kWh of storage.
One viable alternative is getting an inverter that has generator input, via ACin. This will allow you to limp along with less than optimal solar until your battery gets quite low. Then you start up the generator for a few hours to fill back what the solar isn't filling. So, solar by it self might replace most of the power, but the generator fills in the rest if your numbers don't add up.
One viable alternative is getting an inverter that has generator input, via ACin. This will allow you to limp along with less than optimal solar until your battery gets quite low. Then you start up the generator for a few hours to fill back what the solar isn't filling. So, solar by it self might replace most of the power, but the generator fills in the rest if your numbers don't add up.
Yes that could be a good solution, I am looking for that balance between affordability and what I want to power. The needs and goals are mostly food storage during summer and heat via woodburner fan in winter. I do have a small gas generator that can be used, and some way to input that in dire emergency is a fantastic idea. Sure the cost of the solar system would buy a lot of gas one could argue, but we see how things are going in that direction. I really appreciate all your insight, its been helpful. I'm sure I'll have more questions!
If you have an AIO, you can be able to transfer your AC grid input over to generator input and you would be set. I have mine set that way. If I get 3 days of clouds in a row, the generator can charge the batteries enough for the upcoming night.
73powerstroke
Solar Enthusiast
I'm debating the AIO but I'm already deep in this lol. Maybe I'm just confused. I might try both
Not to confuse things but what you describe is not specific to all in ones. My 15+ year old Outback VFX3648 can do that.
MichaelK
Solar Wizard
One nice feature of my XW+6848 is that it has two ACin sets of terminals, so I can seamlessly connect to both the grid and the generator. There is no grid though, so I only have my generator connected to ACin2
wingedlizard
New Member
I started with separate components from Renogy, because I wanted to try it out cheaply.
However, I ended up with an AIO and more panels with much more battery. Now I have enough components for two complete systems.
I could have saved a lot of money by jumping directly to the AIO, since it is a lot simpler. Less Wires, Less tools, Less meters, Less cables. I also went down some dead ends and had extra parts.
If you do go with an AIO, you will probably need two 12v 100ah batteries ( or 1 24v 100ah battery), since the idle draw is more than seperate components which can be turned on and off. Also, you will probably need more panels ( say 350 pv watts or more).
My new system will be the Growatt 3000 24v with 700w of solar and *two* weize 12v lifepo4 100ah batteries. The old system is on a hand truck and the new system will be mounted in my garage. I can expand this system to 2kw ( more panels and more batteries).
My meager expected draw is a refrigerator maybe add a well pump and some deck lights. There are several calculators, I started with the one from http://desertprep.info/ /
The payback period for a system this size is .. never...
However, I ended up with an AIO and more panels with much more battery. Now I have enough components for two complete systems.
I could have saved a lot of money by jumping directly to the AIO, since it is a lot simpler. Less Wires, Less tools, Less meters, Less cables. I also went down some dead ends and had extra parts.
If you do go with an AIO, you will probably need two 12v 100ah batteries ( or 1 24v 100ah battery), since the idle draw is more than seperate components which can be turned on and off. Also, you will probably need more panels ( say 350 pv watts or more).
My new system will be the Growatt 3000 24v with 700w of solar and *two* weize 12v lifepo4 100ah batteries. The old system is on a hand truck and the new system will be mounted in my garage. I can expand this system to 2kw ( more panels and more batteries).
My meager expected draw is a refrigerator maybe add a well pump and some deck lights. There are several calculators, I started with the one from http://desertprep.info/ /
The payback period for a system this size is .. never...
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I keep thinking that is, if you want to do something with solar that asking "how much will it cost?" is sort of funny. Not that you can't do solar on a budget with a good plan, but that there are just so many decision points and options that continuous improvement turns my project into a money pit.
What kind of AIO do you have? Thanks
