Originally posted by khanh dam
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30kw DIY battery for $310/kwh, which hybrid inverter is recommended?
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Originally posted by oregon_phil View Post
Well depth, yield (replenishment rate), static water level and GPM&PSI requirements among other things that will drive well hp requirements. I have had 3hp and 2hp well pumps so far, but not 1hp.Comment
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Originally posted by SunEagle View Post...... I think the pump hp is dependent on the water level and pressure in the hole.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Originally posted by Ampster View PostYes, I looked up a table for pumps and it suggested as @oregon_phil mentioned that it also depends on how much flow one wants. For example a lift of 225 feet could be done with less than a 1 hp pump but the flow would be less than 5 gallons per minute. At that rate you would need a larger tank on the surface depending how how long you want to take showers.Comment
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Originally posted by J.P.M. View Post
That's why pump mfgs. publish pump curves for their offerings.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Just went through this exercise for a customer that wanted a Sol-Ark hybrid inverter. One thing that stood out about this relatively new design is that it has a grid output AC max current over 32amps which means it can't be used for backfeeding without modifying a typical 200A breaker panel. I like the all-in-one design for being easy to set up and it looks like a nice user interface, but even the 8kW version is too powerful for a simple grid tie. Am I wrong about this??
I'm still recommending with the SMA storage bundle using a 10kWh BYD battery. Solidly engineered, proven quality, can be added to an existing grid-tied system, not cheap...BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installedComment
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Originally posted by solarix View Post.....One thing that stood out about this relatively new design is that it has a grid output AC max current over 32amps which means it can't be used for backfeeding without modifying a typical 200A breaker panel........
Or is it that the SMA solution just has less capacity? If that is the case there is a smaller SolArk or the Outback Skybox if one wants to consider an All In One inverter. I have heard good things about SMA offerings but as you mentioned have not seen anything that is competitive with All In One hybrids. I am more interested in understanding the options and relative costs of the solutions. In one sense this may get us back to the title of the thread which was about "which hybrid inverter is recommended?'9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Originally posted by Ampster View PostIf people could read and understand that information and integrate that into an optimum system; there would not be much demand for forums like this.
Q: If all places like this went away how would folks know pump curves exist and how to use them ?
A: The same way they always have - pick up a book and get informed. Alternately these days google "pump curves" or "pump lift + GPM", get swamped with hits and spend 10 minutes learning.
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Originally posted by solarix View PostJust went through this exercise for a customer that wanted a Sol-Ark hybrid inverter. One thing that stood out about this relatively new design is that it has a grid output AC max current over 32amps which means it can't be used for backfeeding without modifying a typical 200A breaker panel. I like the all-in-one design for being easy to set up and it looks like a nice user interface, but even the 8kW version is too powerful for a simple grid tie. Am I wrong about this??
I'm still recommending with the SMA storage bundle using a 10kWh BYD battery. Solidly engineered, proven quality, can be added to an existing grid-tied system, not cheap...
Or is it that the SMA solution just has less capacity?
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Originally posted by oregon_phil View Post
I don't think you are wrong about this. The only other possible thing I found is a "solar ready" 200amp meter panel that has 225 amp bus bars. That way the derating is already baked into the spec so people don't have to do the math.
The SMA high voltage battery inverter is 6.0 kW
Last edited by Ampster; 04-04-2021, 01:13 AM.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Perhaps the transfer switch on the SMA works differently which may make the calculation simpler?
1) Connection to utility grid and household distribution: Maximum input and output current: 200 amp
2) Solar inverter AC connection: Maximum overcurrent protection of circuit breaker of PV inverter:50amps. Inverter AC restriction: 9600 Watt inverter power max (40amps at 240 VAC)
3) Battery inverter AC connection: Maximum overcurrent protection of circuit breaker of battery inverter: 50 amp; (remember one battery inverter per phase so the max here would be 1 SMA 6.0 battery inverter)
It looks like if you went to the trouble of installing the SMA automatic transfer switch, you could still have a 200 amp grid connection and 200 and household distribution when using an SMA battery inverter and SMA solar inverter.
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Originally posted by oregon_phil View Post
The SMA transfer switch spec says the following:
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3) Battery inverter AC connection: Maximum overcurrent protection of circuit breaker of battery inverter: 50 amp; (remember one battery inverter per phase so the max here would be 1 SMA 6.0 battery inverter)
Hopefully this helps the OP evaluate which hybrid is recomended? The answer involves a lot more analysis and understanding than the OP may have thought when he framed the question. For example my Skybox could not handle the surge loads of A/C and the typical deep well pump but it sounds like the SMA can do that easily. Yet each of them could run just fine on a 30 kW(h) DIY battery.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Originally posted by khanh dam View Post
3hp PUMP? I have a 225 foot deep well and it only uses a 1hp pump. maybe you have an above ground pump?Comment
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When I say phase, I had to find an SMA blog posting when talking about SMA battery inverters. The SMA high voltage battery inverter is a 240VAC output device. So one SMA high voltage battery inverter per 240 VAC; not 1 per leg of 240VAC. The other thing is that the SMA automatic transfer switch doesn't manage a generator.
Their offgrid solution is SMA sunny island is a 120VAC output device. So one Sunny Island per 120vac, but you can pair two together for 240VAC.
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Good to know that there is a 240 volt split phase option. Too bad there is not a generator input. That is a feature of the internal transfer switches of most hybrids that adds to their cost effectiveness.
i do know that the generator input on the SolArk is bidirectional so it can be used for AC coupling a GT inverter. That may give SolArk flexibility in meeting the calculations for busbar adequacy by not having to go through the critcal loads panel and with another breaker. That calculation did complicate my Skybox installation with regard to the busbar rating of my critcal loads panel.Last edited by Ampster; 04-05-2021, 03:14 PM.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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