Growatt 2.2kW 3HP Solar Pump Inverter l Water Pump Inverter | Grid-Assisted | SPI 2200TL2-HV

[XILLA]

I have a Solark 15kw Inverter, powered by about 6Kw of panels, and backed up by 25.6Kw of Eg4-Lifepo4 Batteries.

I used about 48kw per day of grid power in the fall to the spring and about 102 kw in the summer ... I live in Phoenix, AZ.

Since I commissioned my system, I have been averaging about 9 or 10kw per day of grid power. This summer of course will be the big test.

My house is almost fully electric. In fact the only thing powered by propane are two tankless hot water heaters. I have lots of big loads ... dryer, oven/stove, well pump, booster pump, swimming pool, hot tub, and 2 three ton HVAC units, and mini-split in my garage (which I rarely use). I have installed Micro Air easy starts on both HVAC and it does help by lowering the start up amp draw.

My hot tub only kicks on a couple of times per day for about 10 minutes to maintain the temp, so the next big drain (outside of the HVAC units) is the pool pump which needs to run about 8 hours per day. I have a Pentair variable speed pump and I have found a sweet spot of running it at about 3,000 RPM and this only pulls about 1380 watts, but still gets the pool cleaned.

My goal now, is to find low cost ways to add to my system in such a way as to use even less grid energy. One thought I have had is to go solar with my pool pump.

I found this Growatt 2.2 inverter specifically made for pumps. Their literature claims it can be used for pool pumps. I can't seem to get Growatt's US offices on the phone, despite repeated attempts.

Growatt 2.2kW 3HP Solar Pump Inverter l Water Pump Inverter | Grid-Assisted | SPI 2200TL2-HV

Signature Solar provides solar panels, off-grid solar systems, grid-tie, and hybrid systems. Quality solar inverters, bifacial solar panels, complete solar kits, solar batteries. Featuring brands such as EG4 Electronics with their solar battery, LifePower4 and EG4 LLifePower4 and EG4 LL

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So, does anyone have experience with this product, specifically using it for a pool pump? I guess my biggest concern is that the Pentair pool pump is controlled through a control panel and I just want to ensure that the Growatt product will properly interface and not mess up the system. It claims it can pull power from the grid and solar seamlessly.

Any help, advice, loose ramblings, ruminations, or advice found in consulting the tea leaves will all be appreciated!

I am new to the solar world, and now addicted to trying to minimize my grid usage!

 

[XILLA]

One more thing ... I have a quote from my solar installer to add another 6k worth of panels to my Solark system. He wants $11,400. I would also want to couple that with another 20k worth of batteries. All in, it would cost me $17k-ish. The Growatt inverter is $400 delivered and I can but cheap solar panels from Santan solar hear locally. The panels I am looking at run about $100 each and I was looking to buy 8 of them. So, the cost difference is massive but not sure if my entire plan makes sense or not.

 

[OzSolar]

Welcome to the forum!

What you want is a variable speed pool pump.

Slight reductions in pumping speed have dramatic reductions in energy usage.



Check out NREL's paper for more information.

https://www.nrel.gov/docs/fy12osti/54242.pdf

 

[XILLA]

Hi OzSolar,

I noticed that myself as I initially had my pump turned all the way up to the max. In 8 hours of pumping I was consuming (this time of year) about six hours direct from PV and then about two hours from the battery.

Xilla

 

[1201]

.

Since I commissioned my system, I have been averaging about 9 or 10kw per day of grid power. This summer of course will be the big test.

For 6kw of panels that's not bad. So your inverter supports all the loads from pv and battery and when battery gets low then the power comes from the grid?

Since you are already connected can you find the labor and electrician to add the additional panels for less? 6kw of panels is about $1800, and mounting may be another 1200, so about $4000. A guy can install those in two days for say $1000 and your electrician can hook everything up

 

[XILLA]

For 6kw of panels that's not bad. So your inverter supports all the loads from pv and battery and when battery gets low then the power comes from the grid?

Since you are already connected can you find the labor and electrician to add the additional panels for less? 6kw of panels is about $1800, and mounting may be another 1200, so about $4000. A guy can install those in two days for say $1000 and your electrician can hook everything up

So your inverter supports all the loads from pv and battery and when battery gets low then the power comes from the grid? - Yes that is correct.

Since you are already connected can you find the labor and electrician to add the additional panels for less? 6kw of panels is about $1800, and mounting may be another 1200, so about $4000. A guy can install those in two days for say $1000 and your electrician can hook everything up. - Its a great idea! That would certainly save some serious money. My worries are that I had a hard time finding someone who really understands solar with batteries. Most people simply want to do an interconnection agreement with the local utility. I think I would have to better understand how to set up the solar panels so that I could direct the electrician i.e. How many in series/parallel.

 

[1201]

So your inverter supports all the loads from pv and battery and when battery gets low then the power comes from the grid? - Yes that is correct.

Since you are already connected can you find the labor and electrician to add the additional panels for less? 6kw of panels is about $1800, and mounting may be another 1200, so about $4000. A guy can install those in two days for say $1000 and your electrician can hook everything up. - Its a great idea! That would certainly save some serious money. My worries are that I had a hard time finding someone who really understands solar with batteries. Most people simply want to do an interconnection agreement with the local utility. I think I would have to better understand how to set up the solar panels so that I could direct the electrician i.e. How many in series/parallel.

Since you live in Phoenix and have a solark 15k with 600v input. Depending on the panels you select, you could probably put 6kw of panels)about 15x 400w panels) in series. That would make it extremely simple and efficient. Just two 10 gauge wires to run to + and - of the solark pv inputs.

This would be very simple to do. You wouldn't even need overcurrent protection

 

[XILLA]

Hi 1201,

Thank you for the input! Currently I have twenty-two REC 260w panels in three strings feeding the inverter. There appears to be three more PV inputs. So, would I take the 400w panels in just one string into the inverter or should I break it up into three separate strings? Are there any issues with the fact that my current array is only 260w panels?

 

[1201]

Hi 1201,

Thank you for the input! Currently I have twenty-two REC 260w panels in three strings feeding the inverter. There appears to be three more PV inputs. So, would I take the 400w panels in just one string into the inverter or should I break it up into three separate strings? Are there any issues with the fact that my current array is only 260w panels?

If you don't have shading issues, Doing one string has advantages. Lower voltage drop, higher efficiency . We have to make sure the panels you're going with will never exceed the 600v. There is a midnite Barcelona calculator you can use and input your panel specs.

With the Canadian solar panels or Talesun panels with 37voc, you should be able to do 15 in series. Or at least 14

 

[XILLA]

Ok, perfect. Thank you!

 

[Recap]

I contacted Growatt about the

Growatt 2.2kW 3HP Solar Pump Inverter l Water​

and they told me it SHOULD work but they don’t know how to wire it to a pump other than a holding tank. I have a pressure switch on my well pump. So it seems the Growatt water pump is only meant for wells that use a storage tank. I know someone on this forum used it on a pool pump but did not post the wiring. The advertised documentation says pool and water pumps but Growatt doesn’t know how to wire it. They told me they called China. Any thoughts?