What component to install first if installing one component at a time?

[MapleGuy]

I am looking to eventually install a complete 8-10kwh solar system with a battery backup that will be grid-tied, using the grid to supplement any power that I might need. I want to pay for the system as I can afford components as I can't afford the entire system at once. I'd like to add capacity as I go along, either on the solar side or storage side but will size the "middleware" components for what I would eventually need. As a general rule, what would be the first component that I should target installing? I'm thinking that would be a grid-tied inverter and an emergency shut-off switch but I wanted to get some feed back.

Likewise, is there a guide laying out what order components should be installed in? My thinking is that once that is in, I can work on the solar array as time/money is available and connect it to the inverter which would already be in place. Likewise I could add a battery array as finances allow and keep doing that until I've reach my goal.

 

[MisterSandals]

If you used micro inverters, you could add solar panels, each with a micro inverter, incrementally.
This is probably easiest to start with and perhaps the best way to add on incrementally.

The problem with this is the availability of finding matching panels as time passes. A rooftop with mismatched panels is unsightly.

 

[timselectric]

You said "grid-tied", so you want to sell excess power to the grid? This will require an agreement with your grid supplier. Or, did you just want to use the grid as a backup?
This makes a difference in what equipment you choose.
Either way, if you want to scale up as funds become available. You will probably want to look at stackable AIO's.
Start with one, then add solar, followed by some battery capacity.
This will allow you to expand on all fronts, in the future.

 

[MapleGuy]

If you used micro inverters, you could add solar panels, each with a micro inverter, incrementally.
This is probably easiest to start with and perhaps the best way to add on incrementally.

The problem with this is the availability of finding matching panels as time passes. A rooftop with mismatched panels is unsightly.

That's a valid point. I'll look into using those but I think when I initially researched options, I think I read that they weren't the best choice if a battery backup was desired. I'd have to look at what components would be needed because I'd still need a way to connect back to my house grid.

 

[Ampster]

It may be more economical to purchase an All In One unit instead of separate charge controllers and inverters. Then all you would need is batteries and solar panels. Depending on the AIO, some work without batteries.

 

[khisanthax]

I did what you wanted to do, but the wrong way, at least in terms of knowing how to match components together. I tried doing 8 panels, and AIO and a 48v 50AH battery. I overpayed for the panels (amazon) and will eventually have to use better and different panels. I choose an inverter that was only 120v when I should have chosen a 120/240v split phase inverter because I have loads that require 240v. About the only thing that I think is fine for now is the battery. I would return my panels but the thought of the hours I spent installing the 8 panels on the roof and spending a few hours to uninstall them and plug the holes is too painful, so I'll probably put them on a seperate PV charger later on when I'm ready to get the panels that are worth it.

I think what components you get first depends on what function, if any, you want first. If nothing is going to be put to use until everything is together then it doesn't matter. Like Ampster said, I think an AIO does save money if you get the right one and plan for what you need now and in the future. Either way you would probably need the inverter aspect first if you wanted to do anything with it before having everything at hand. I've only been here for a week or two, so someone might correct me on this!

 

[MapleGuy]

You said "grid-tied", so you want to sell excess power to the grid? This will require an agreement with your grid supplier. Or, did you just want to use the grid as a backup?
This makes a difference in what equipment you choose.
Either way, if you want to scale up as funds become available. You will probably want to look at stackable AIO's.
Start with one, then add solar, followed by some battery capacity.
This will allow you to expand on all fronts, in the future.

I'm really not interested in selling power back, just having access to power if I needed it, particularly on "darker" winter days or a cloudy week.

 

[Hedges]

A hybrid (AIO) that is grid-interactive, able to blend power from PV and/or (optional) battery with grid power, able to backfeed or do zero-export (optionally just for downstream loads, or with CT at meter for whole house) would be the most flexible.

There are a number of economical AIO, not sure how many are grid-interactive UL-1741-SB.
SolArk should do it all, and can be stacked in parallel or for 3-phase.
I'm waiting to learn the specs for SMA's Sunny Boy Smart Energy. It is to replace Sunny Boy, so I expect a price in the $2500 range. It unfortunately takes high voltage battery which is more expensive than many 48V models.
Up to 11.4kW, but I don't expect it to be stackable.
(for those in European market, there is already a 3-phase version available there.)
I expect to install it on a couple of homes, where we have reservation with PG&E for the previous models.

Discover the Sunny Boy Smart Energy | SMA America

The hybrid inverter at the heart of the SMA Energy System, with three backup options: Sunny Boy Smart Energy ► Discover now!

www.sma-america.com

 

[timselectric]

I'm really not interested in selling power back, just having access to power if I needed it, particularly on "darker" winter days or a cloudy week.

Then, you can go with an off grid AIO.
Just make sure that you choose a stackable one.
And the best advice I can give is to plan for the future before you start spending money. You can buy and build in phases. But knowing the end project, keeps you from doing things twice.

 

[MapleGuy]

I did what you wanted to do, but the wrong way, at least in terms of knowing how to match components together. I tried doing 8 panels, and AIO and a 48v 50AH battery. I overpayed for the panels (amazon) and will eventually have to use better and different panels. I choose an inverter that was only 120v when I should have chosen a 120/240v split phase inverter because I have loads that require 240v. About the only thing that I think is fine for now is the battery. I would return my panels but the thought of the hours I spent installing the 8 panels on the roof and spending a few hours to uninstall them and plug the holes is too painful, so I'll probably put them on a seperate PV charger later on when I'm ready to get the panels that are worth it.

I think what components you get first depends on what function, if any, you want first. If nothing is going to be put to use until everything is together then it doesn't matter. Like Ampster said, I think an AIO does save money if you get the right one and plan for what you need now and in the future. Either way you would probably need the inverter aspect first if you wanted to do anything with it before having everything at hand. I've only been here for a week or two, so someone might correct me on this!

I think I'd want 240 so I could power the whole house.

Do you guys have an example of an all-in-one unit? This is the inverter that I was going to have installed. Is this considered an all-in-one unit?

XW Pro 120/240V

The Schneider Electric XW Pro 6848 solar inverter provides flexible design with optional generator integration for home and small businesses.

solar.se.com

 

[timselectric]

A typical AIO has an inverter, solar charger, AC charger, and transfer switch, All In One unit.

 

[timselectric]

Several discussed here.

All-in-One Systems

diysolarforum.com

 

[Solar Guppy]

All that your doing by buying a part now is caving too some type of emotional impulse, there is no way it ends with the final system, yet planned or designed of being built.

I would suggest you start saving and when you have the funds to build a complete system, then you purchase all at once and build with permits as will be required in your state.

Buying random parts over time will end at best with different generations of technology and likely pay more for things that will possibly be outdated or no longer support by the manufactures, possibly they have gone out of business.

For example, matching the solar, panels keep getting bigger and lower cost, battery costs will likely see a large decreases.

BTW, it isn't about having the means, but a long process of learning, planing, implementing and the reward you did it. I hope you are successful in this endeavor!

 

[Quattrohead]

Eg4 18k or Solark 15k are all in ones that would work for you, both quite easy to install.
Add 1 string of panels 3-5kw and 10-20kw of batteries.
Then add another set of panels and batteries as funds allow.

 

[timselectric]

It's actually the "EG4 18kpv".
Both the 18kpv and Sol-Ark "15k" are hybrid AIO's. (Both are actually 12k units , despite their deceptive names)
So, grid-tied and capable of AC coupling.
Which are features that you will be paying for, that you don't need.
Hybrid AIO means grid-tied and capable of off grid use.
Off grid AIO means capable of off grid use and able to use grid as backup.

 

[MapleGuy]

All that your doing by buying a part now is caving too some type of emotional impulse, there is no way it ends with the final system, yet planned or designed of being built.

I would suggest you start saving and when you have the funds to build a complete system, then you purchase all at once and build with permits as will be required in your state.

Buying random parts over time will end at best with different generations of technology and likely pay more for things that will possibly be outdated or no longer support by the manufactures, possibly they have gone out of business.

For example, matching the solar, panels keep getting bigger and lower cost, battery costs will likely see a large decreases.

BTW, it isn't about having the means, but a long process of learning, planing, implementing and the reward you did it. I hope you are successful in this endeavor!

Respectfully, I disagree about satisfying an emotional impulse. I'm looking to reduce my electric bill, decrease my grid reliance, increase my resiliency and be better off for it. It's a process. Nothing happens all at once. Nothing.

 

[timselectric]

Respectfully, I disagree about satisfying an emotional impulse. I'm looking to reduce my electric bill, decrease my grid reliance, increase my resiliency and be better off for it. It's a process. Nothing happens all at once. Nothing.

I'm 3 phases and a year and a half into my system. Believe me, I understand.

 

[Solar Guppy]

Respectfully, I disagree about satisfying an emotional impulse. I'm looking to reduce my electric bill, decrease my grid reliance, increase my resiliency and be better off for it. It's a process. Nothing happens all at once. Nothing.

Purchasing a part or two won't help in your goals, saving money and making a detail plan and then building it will in the end.

 

[Hedges]

I'm looking to reduce my electric bill, decrease my grid reliance, increase my resiliency and be better off for it.

If you want to reduce your electric bill, first step is to determine net-metering terms, and any plans for those terms to change. If no net metering, could be zero export (use it or lose it regarding PV), or battery based.

Ignoring battery backup ("decrease my grid reliance, increase my resiliency"), grid-tie PV with net metering is the way to reduce electric bill. Hardware costs $1.00 to $1.30/W, and amorized over 20 years will produce power for $0.025 to $0.03/kWh. Turn-key installed will cost $2.00 to $4.00/W and produce power for maybe $0.075 to $0.12/kW

Operating with the grid down is a big jump it hardware requirements and cost, if you want to run motors. Backup of internet connection is simple enough. Backup of electric heat is impractical if not impossible.

You have to "audit" or otherwise tabulate your needs for peak operating watts, motor starting surge watts, watt-hours per day. Then you can identify inverters able to do that, and design a system with batteries and PV around them.

 

[MapleGuy]

Purchasing a part or two won't help in your goals, saving money and making a detail plan and then building it will in the end.

I've already been researching and planning this for several years. Your assumption is that I haven't. I know the design of my system but wanted input on what to install first. Again, I respectfully disagree that my electric bill won't go down over time and that I wouldn't have electricity when the grid is down. I appreciate the feedback though.