New Construction Sol-Ark 15K

[hautions11]

Hi Everyone, Building a new house and I would like to get a good baseline for a battery/solar house. Since the electricians are here in a few weeks, I want to install the basics right up front, designed around a Sol-Ark 15k. I have read a lot of comments on overwhelming the Sol-Ark running a 200 amp panel, so I am trying to avoid that.

I am on the grid and the basic goal is to minimize dependency on the grid and get some grid down security.

I am starting with a 320 amp service. My thought is a 200 amp main box powered by the Sol-Ark. I will put a variety of large loads in the second 120 amp panel. In the 120 amp panel are; EV charger, 220 circuite for table saw, planer shop tools, emergency power strip for geothermal, dryer, mini-split (porch/garage) and electric oven. My idea is to try eliminate non essential big loads off the main 200 amp panel.

Eventually I want a 6-8 KW solar array, but not in the initial install. I am thinking DC input from the solar. The house is tight with Spray foam and an ICF walk out foundation.

My big loads on the 200 amp panel; 3 ton geothermal pulling 2.3 KWH, heat pump hot water heater, ( geothermal heats water all summer while in AC mode), cook top,( oven on non-essential panel)

So, I was looking for some thoughts on up front ideas that I should not miss to make sure I incorporate the key items and features.

I am debating on wiring in a small inverter generator for any Mutiple day power outages. I have seen a lot of discussion on using the GEN function for other functions.

Fire away, i am open to any input.

 

[Hedges]

Generator costs $1.00/kWh, PV costs as little as $0.025/kWh (amortized over 20 years, if you use all the power.)
Not sure about SolArk, but some inverters work with arbitrarily small generators and supplement its power. Or DC couple and inverter remains the voltage/frequency source.

Starting surge of motors is key parameter to design around.

Inverters have limited peak power (e.g. 12kW from battery is 100A at 120V, 50A at 240V) and limited battery capacity. But, it may be convenient to at least be able to switch those big loads to run off inverter. Even things like oven, so long as PV can carry them. Interlocked breakers can support that. SoC and wattage based control of loads could be convenient.

Starting from scratch I would think about 3-phase. Was going to do that for my new house, but utility hookup charge was excessive. You could feed a 240V load panel from the grid, have one leg feed a 120/208Y 3-phase inverter for workshop. If grid down, 208V to the 240V panel for battery backup.

SolArk has a popular following. I don't know how it is for surge loads, but it is stackable.
There are other (actually) tier-one manufacturers to consider, including Schneider and SMA. They may or may not have a better system for your needs (component rather than AIO)

"Eventually I want a 6-8 KW solar array, but not in the initial install. I am thinking DC input from the solar."

You ought to put in lots of PV. Can be $0.50/W for the panel, even lower used. Double or triple that amount, for a single SolArk. PV panels themselves are almost the lowest cost part of your system, and more means more production even when overcast or off season.

 

[hautions11]

Thanks for the input, the Sol-Ark idea is based on a single inverter to handle all the functions. I never thought of 3 phase, I will look into it.

I can add PV as I go on. I agree it is the best power development option. I just dont want to miss anything on the up front install while I have the electricians at the house.

 

[Hedges]

I see you're in Indiana, not California, so don't have that near-term deadline regarding net metering. If you have good net metering, that changes what you need in terms of batteries. Grid Tie PV can be much more cost effective, and battery backup can be sized just for critical loads. SolArk for $8000 gives 12kW of backfeed (or is it good for 15kW?), compare to 2x Sunny Boy for $3500. But it includes battery backup and 200A transfer relay. I think it is batteries optional so you can leave that expense for later. Adding 2x Sunny Island at retail would cost a lot more, but liquidation deals close to same cost. I haven't kept track of other brand prices.

It is good to pencil out planned additions. Size conduit for future wire fill and oversize beyond that (max allowed fill seems only possible stuffing through a short straight section, not pulling around corners.) Have extra Tee to allow adding equipment, and consider whether wires have to go out and back for manually selected backup - conduit fill and derating.

SolArk, Outback, SMA, Schneider all can be configured 3-phase, I think. At least with SMA, I can have the master connected to single phase 120V (56A max) and slaves will create the missing phases. That's a bit limited on wattage but does give the functionality. Cost-wise, VFD is cheaper way to drive motors and soft-starts. But cheap VFD with poor power factor upset my GT PV inverters.

SolArk I think claims quality and features not found in very similar units from same manufacturer, but it seems hard to consider it tier one. Not that I've heard of a failure rate problem, like some big-name grid tie inverters. But some other brands are long-term solid products with a reputation that everyone would agree are tier one. Despite the markup compared to overseas brands, SolArk still has a good price point for performance and being AIO saves a lot in miscellaneous parts and labor.

https://files.sma.de/downloads/SISYSGUIDE-KEN140421.pdf

 

[Shimmy]

Install all the PV up front. The only loads that should be on the non backed up panel (panel should be rated 200A even if there is only really 120A "capacity" for it) are the (second) EV charger, your dryer, any resistive hot water heating elements, and an electric oven if you have one. A 12kW inverter can deal with everything else a modern home will throw at it.

You might consider radiant or mist cooling for the portch, and a hydronic heated/chilled slab for the garage if it is a new house; just keep slab temperature a few degrees above dewpoint and it is a nice space. Heating is usually fine at ~55F. If the loads are just silly things then sure, you can put them on the non essential panel.

Also... if you need a 320A service you need to plan for 16kW of PV. Install 10-12kW initially and save a MPPT input for another ~6kW.

 

[hautions11]

Indiana screwed up net metering last year! it was 1;1 and now it is wholesale or 2 to 3 cents. The 320 amp service is relatively cheap up front and it allows for future upgrades. Yes I will have 2, 200 amp panels. Im calling one a 120 just to differentiate between them.

I guess im nervous about taking load off the main panel from various posts on out of balance from T1 to T2 etc. Maybe I am being overly conservative.

 

[hautions11]

Also thinking about SOK battery bank

 

[DougfromdaUP]

Install 12kW of photovoltaics at the get go. You're spending a ton of money on inverter, conduit, cable, disconnects, etc. You'll have everything in place except for panels. For a small percentage more you can really use your investment.

You'd have plenty of energy for power outages 80% of the year (or more.)

 

[DIYrich]

Skip the separate 120 amp panel, and get something like the Savant Power Management System instead. When they wire the system, have them put in Busbars so you can easily add a second Sol-ark 15k.

One Sol-Ark can do 50 amps @ 240v. Put a second in parallel, and you have 100 amps @ 240v. That should be enough power to run all but the EV charger. The Savant power management system will turn off circuits (EV charger, shop tools, whatever). But, you retain the ability to turn them back on if you need them. Savant can also turn them on if there is sufficient power (summer, and you are producing a lot while off-grid).

4kW is the minimum generator input directly connected to the Sol-Ark, so you need a 5kW generator to keep it at 80%. I have 30kWh of batteries, and got the Chargeverter and Wen DF475T (Dual Fuel, 3,500 watts on LPG at 240v). It is a cheap regular generator. Run it for 10 hours to directly charge the batteries, and you don't have to worry about THD. You could get the Wen df875Ix, inverter 6,300 watts (5,040 @ 80%) on LPG, and directly feed the Sol-Ark. One benefit of the Chargeverter, is in the event the generator fails, you can pick up any cheap 240v generator and plug it in (110v if you want to run at reduced max wattage of the Chargeverter).

 

[EastTexCowboy]

Are you installing something in the way of a transfer switch, either auto or manual? It sounds like you're putting quite a bit on the solar CL panel. It would be nice to have a way to transfer that load back to the grid if you need to do maintenance or have a component fail.

I agree with several of the other comments here on installing the panels as part of the initial build. Not only will you get payback right away but including it in the build should be easier and maybe even cheaper than installing as an add-on down the road.

 

[hautions11]

I just saw a review that Will did on the chargeverter, that looks like a good solution for simple emergency charging.


It really sounds like I need to get started on solar. My yard is still a mudhole and needs a bit of bulldozer time, so I need to put off permanent ground mounts for a while. I do have a spot on my south facing 40 X 27 garage roof. There are some slick mounts that attach to the standing seam roof

 

[Hedges]

Is that the garage roof? With so much shade from trees?
You're going to have to choose one or the other.

 

[Danke]

You can pass through 400A if you have two Sol-Ark‘s.

 

[ImAnIdiotPleaseBePatient]

Generator costs $1.00/kWh, PV costs as little as $0.025/kWh (amortized over 20 years, if you use all the power.)
Not sure about SolArk, but some inverters work with arbitrarily small generators and supplement its power. Or DC couple and inverter remains the voltage/frequency source.

Starting surge of motors is key parameter to design around.

Inverters have limited peak power (e.g. 12kW from battery is 100A at 120V, 50A at 240V) and limited battery capacity. But, it may be convenient to at least be able to switch those big loads to run off inverter. Even things like oven, so long as PV can carry them. Interlocked breakers can support that. SoC and wattage based control of loads could be convenient.

Starting from scratch I would think about 3-phase. Was going to do that for my new house, but utility hookup charge was excessive. You could feed a 240V load panel from the grid, have one leg feed a 120/208Y 3-phase inverter for workshop. If grid down, 208V to the 240V panel for battery backup.

SolArk has a popular following. I don't know how it is for surge loads, but it is stackable.
There are other (actually) tier-one manufacturers to consider, including Schneider and SMA. They may or may not have a better system for your needs (component rather than AIO)

"Eventually I want a 6-8 KW solar array, but not in the initial install. I am thinking DC input from the solar."

You ought to put in lots of PV. Can be $0.50/W for the panel, even lower used. Double or triple that amount, for a single SolArk. PV panels themselves are almost the lowest cost part of your system, and more means more production even when overcast or off season.

Sol ark makes a 60kw inverter, but you have to be on 480 3-phase

 

[Hedges]

I think 15k can be wired 120V single phase, and 3x configured for 120/208Y.

I connected 3x SI 5048US that way, added at transformer to make 277/480Y for TriPower.
SI will create the missing phases. I don't know if SolArk will.

 

[Danke]

I think 15k can be wired 120V single phase, and 3x configured for 120/208Y.

I connected 3x SI 5048US that way, added at transformer to make 277/480Y for TriPower.
SI will create the missing phases. I don't know if SolArk will.

 

[hautions11]

On the solar panel front, EG4 seems to make an inexpensive ground mount that could be temporary for a few months this summer, while I finish the yard. I notice they are out of stock. Has anyone watched these on the site for a while? do they tend to go in and out of stock like batteries. I would love to grab a couple as a temporary solution

 

[hautions11]

My Sol-Ark was delivered today and a rack and a couple of batteries get here later in the week. My electrician will install them while he is wiring the rest of the house. That is the easiest way for me to get that part of the system inspected and bought off. After the yard dries out and I get it graded, I can work on ground mounts.

 

[hautions11]

I did freak out a bit today, as I researched permits for grid tie solar panels. 5-6 pages, drawings, wind loads etc. I called our local authorities and got a great response. Oh, items you bring, pictures of the house, an idea on the # of panels roof mounted or ground mounted. Drawings, specs, data sheets, no we don't need any of that. You have to love central Indiana.

 

[hautions11]

I have been busy with the house, but the solar project is moving along. Sol Ark is installed next to the two panels. The non Sol ark panel is mostly 220, non essential...dryer, oven etc. The main panel runs 90% of the house. 320 amp service. From a good suggestion here, I added a transfer switch that takes the Sol Ark out of the loop and the main panel goes straight to grid. If the Sol Ark goes down or has a software issue and my wife is home alone, push the transfer and go straight to grid, work on the inverter issues later. A couple of pictures.





Pretty excited, Duke comes out next week to inspect and then we have power to the house. Ordering panels next week, doing an install on the standing seam roof.