diy solar

diy solar

Sol-Ark 12K + Enphase IQ8 microinverters

I do not have a SolArk and have always been confused why SolArk recommends to wire AC coupled inverters directly to the Generator port. That is inconsistent with how my Outback Skybox uses the bidirectional AC out port to the Critical Load panel and the AC coupled inverter(s) to the CLP. I recently saw an explanation that was purely anecdotal that said the reason the SolArk prefers to AC couple through the Generator port is that allows them to use the Generator port relay to open the connection if the SolArk cannot ramp down the AC coupled inverter(s} fast enough. That seems like a klunky solution.

If that is the case, it would be a limitation of the SolArk in terms of being able to AC couple and use a generator, More importantly is suggests to me that the algorithm that SolArk uses for AC coupling is limited in functionality.
I have a enphase IQ7+ based installation. I wanted to add a SolArk in order to provide off line backup capability and to tie in some LiFePo4 generic batteries. (also doubling my solar at the same time) At nearly $1,000 per KWHr the Enphase battery products are just out of the ball park especially if you are looking for backup for several days. i.e. 70 KWHr. Its $70,000 compared to $10,000. So if you do that comparison the cost savings are not in "just" replacing the Enphase smart switch.
I spent a lot of time on the phone with SolArk customer support as well as a lot of emails. Here is what I learned. The SolArk solution to the AC coupled microinverters is all on or all off. There is NO throttling of the output even though the micro-inverters are capable of doing so. Therfor they HIGHLY advise that the DC coupled solar be approximately equal to or greater than the AC coupled solar. That way they can use the DC coupled solar to throttle up and down since it runs through the MPPT in the SolArk. If they run out of that flexibility or do not have it, under numerous scenarios, they will just turn off the AC coupled micro-inverters. That can mean a lot of lost solar power.
Regarding the AC coupling, based on their manual, that can be done through the generator port or can be done through the Aux panel. The problem with that is if you do run your AC coupling through the Aux port then, according to them, you CAN NOT use the generator! So that really sucks, so I spent some time pushing back trying to figure out why they would not allow this. At the end of all the conversations they just said that due to the internal electronics and actions in the SolArk there are conditions where current can be fed back into the generator resulting in catastrophic failure of the generator and/or the SolArk.
The only7 alternative that I could see was if you want to run a generator AND your AC coupled solar you may have to buy a separate charger that runs exclusively off your generator to charge your batteries. This does not help running your house directly from the generator energy but if you look at the system it is not a bad option. The big problem is that it adds money to the solution when you have a perfectly capable charger going to waste in the SolArk.
For my case this may actually work out well but for others maybe not so much.
 
That is not a very robust implementation of AC coupling. I understand why it works better if you have DC coupled solar because the MPPT controller can react faster. My Skybox is the same way. But at least the Skybox can modulate the AC coupled inverters.
 
I have a enphase IQ7+ based installation. I wanted to add a SolArk in order to provide off line backup capability and to tie in some LiFePo4 generic batteries. (also doubling my solar at the same time) At nearly $1,000 per KWHr the Enphase battery products are just out of the ball park especially if you are looking for backup for several days. i.e. 70 KWHr. Its $70,000 compared to $10,000. So if you do that comparison the cost savings are not in "just" replacing the Enphase smart switch.
I spent a lot of time on the phone with SolArk customer support as well as a lot of emails. Here is what I learned. The SolArk solution to the AC coupled microinverters is all on or all off. There is NO throttling of the output even though the micro-inverters are capable of doing so. Therfor they HIGHLY advise that the DC coupled solar be approximately equal to or greater than the AC coupled solar. That way they can use the DC coupled solar to throttle up and down since it runs through the MPPT in the SolArk. If they run out of that flexibility or do not have it, under numerous scenarios, they will just turn off the AC coupled micro-inverters. That can mean a lot of lost solar power.
Regarding the AC coupling, based on their manual, that can be done through the generator port or can be done through the Aux panel. The problem with that is if you do run your AC coupling through the Aux port then, according to them, you CAN NOT use the generator! So that really sucks, so I spent some time pushing back trying to figure out why they would not allow this. At the end of all the conversations they just said that due to the internal electronics and actions in the SolArk there are conditions where current can be fed back into the generator resulting in catastrophic failure of the generator and/or the SolArk.
The only7 alternative that I could see was if you want to run a generator AND your AC coupled solar you may have to buy a separate charger that runs exclusively off your generator to charge your batteries. This does not help running your house directly from the generator energy but if you look at the system it is not a bad option. The big problem is that it adds money to the solution when you have a perfectly capable charger going to waste in the SolArk.
For my case this may actually work out well but for others maybe not so much.
This is the exact same thing I am thinking of implementing. I am not looking to have a generator anytime soon. I would like to keep my options opened.

In Arizona , I will be on a demand based pricing system if I go solar. Usage is only. 05 kwh on average. Both on and off peak. The ROI is in reducing the demand charges to zero. I want to implement a battery so that I can supplement the pv when needed to meet our demand and pull zero from the grid during on peak times.

Reading up on the batteries, they are 100amp constant. That is 4.8kw. My demand averages about 6wh. So, I'm thinking I may need to add a second Sol Ark so I can double that to 9 6kw.

This may make it too costly
 
That's completely different from what they used to say. They have always claimed to be able to frequency shift.
 
Reading up on the batteries, they are 100amp constant. That is 4.8kw. My demand averages about 6wh. So, I'm thinking I may need to add a second Sol Ark so I can double that to 9 6kw.
I do not understand your math? Is that correct that your demand charges are only 6 Watt hours? If so, why do you need to add another SolArk?
 
This is the exact same thing I am thinking of implementing. I am not looking to have a generator anytime soon. I would like to keep my options opened.
Reading up on the batteries, they are 100amp constant. That is 4.8kw. My demand averages about 6wh. So, I'm thinking I may need to add a second Sol Ark so I can double that to 9 6kw.

This may make it too costly

Another SolArk?
Can the first one work with another battery?
 
This is the exact same thing I am thinking of implementing. I am not looking to have a generator anytime soon. I would like to keep my options opened.

In Arizona , I will be on a demand based pricing system if I go solar. Usage is only. 05 kwh on average. Both on and off peak. The ROI is in reducing the demand charges to zero. I want to implement a battery so that I can supplement the pv when needed to meet our demand and pull zero from the grid during on peak times.

Reading up on the batteries, they are 100amp constant. That is 4.8kw. My demand averages about 6wh. So, I'm thinking I may need to add a second Sol Ark so I can double that to 9 6kw.

This may make it too costly
my guess is your BMS limits the battery to 100A. New BMS that supports 200A will cost you $200. OR get another battery with a 100A BMS.
The SolArk will support multiple batteries in parallel.
 
I do not understand your math? Is that correct that your demand charges are only 6 Watt hours? If so, why do you need to add another SolArk?
My utility charges based on demand you put on the grid. The kwh charge is miniscule. So, the game is eliminating demand on tge grid not necessarily usage.
Demand is calculated during peak hours. 2-8pm on weekdays. From 5-8, your PV is producing less than half. I bet it's around 30% or less and going down. Using battery power that you stocked up on earlier in the day, you use during that 5-8 window to ensure you do not put a demand on the grid. After 8pm, who cares. It's all off peak and demand is not calculated.

If the batteries can only discharge up to 4.8k and I use 6 on average (could be m9re. It is dinner time. So microwave or stove raises your demand) . So, I think I'll need a second inverter so that I can get 4.8k each for a total of 9 6k. Then I would almost be ensured I would not put a demand on the grid.


SRP demand plan

Tell me I'm thinking of it wrong. I already play a time of use plan with SRP where I turn off my AC and almost everything else to keep usage low. I don't want to spend money for solar to playvthe same game but just between a different set of hours.

Screenshot_20220731-180333_Chrome.jpg
 
They do frequency shift. The frequency shift until the ac coupled solar turns off. What they don’t do is modulate the power.
The IQ7s are UL1741SA compliant, which means they can modulate their power in response to the grid forming inverter shifting frequency. If the SolArk algorithm is any good it should be able to do frequency shift in increments to cause the IQ7s to modulate. If the SolArk algorithm is klunky it may not be able to do frequency shift in discrete increments and all it can do is quickly ramp up frequency or cut out the Generator out relay causing the IQ7s to turn off or rapidly modulate which may look like the same thing.
 
I do not understand your math? Is that correct that your demand charges are only 6 Watt hours? If so, why do you need to add another SolArk?
So, could I put 2 batteries in series for 96volt at 100 amps and get the 9.6 kw constant discharge?
 
I undestand how demand charges work Your original post said 6 W hour, so change your original post to read 6kW instead of 6W. That is a big difference.
In context, I was speaking in kw. But, I can see that it lacked clarity
 
They do frequency shift. The frequency shift until the ac coupled solar turns off. What they don’t do is modulate the power.
The micro inverters modulate their own power. Whenever the frequency shifts. But, Sol-Ark is now saying that they can't control the micro inverters. Which means that they evidently can't shift the frequency. They are now saying that they can only disconnect them from the system.
(According to post #81)
 
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The micro inverters modulate their own power. Whenever the frequency shifts. But, Sol-Ark is now saying that they can't control the micro inverters. Which means that they evidently can't shift the frequency. They are now saying that they can only disconnect them from the system.
(According to post #81)
The Sol Ark disconnects them?
 
The micro inverters modulate their own power. Whenever the frequency shifts. But, Sol-Ark is now saying that they can't control the micro inverters. Which means that they evidently can't shift the frequency. They are now saying that they can only disconnect them from the system.
(According to post #81)
Correct, by frequency shifting they can turn them off or turn them back on. There is no way they can throttle them to a specific amount of power. I was thinking that this might be a feature of the upcoming Sol-Ark MicroInverters but I am hearing that it is not.
 
So, could I put 2 batteries in series for 96volt at 100 amps and get the 9.6 kw constant discharge?
Looking at the spec sheet, the Sol Atk says the DC input is 48 v nominal. So, cannot put 2 EG LL in series to get me enough kw to cover my demand needs when PV is low. Maybe the sol ark is too expensive for me. If I can find a cheaper inverter alternative to allow me to be grid tied but be off grid and meet 6kw average demand. I'm doing solar to save money. Maybe I should invest in a variable speed heat pump instead
 
According to post #81. Sol-ark said that the micro inverters had to be connected to the generator input. So that they could turn them off by opening the circuit.
 
According to post #81. Sol-ark said that the micro inverters had to be connected to the generator input. So that they could turn them off by opening the circuit.
I could have sworn that in Bens Sol-Ark video he said they Frequency shit to 62Hz to shut them off.
He has both systems running at his house and he is a Sol-Ark installer.
 
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