If an ATS separates an existing grid-tie inverters from a new off-grid system, can the same solar panels be used with both inverters?

[summit]

Here is a link for a 50 amp 5500 watts external automatic transfer switch to island the critical load panel per your description using a 5 KW inverter or grid power: https://www.amazon.com/MOES-Controller-Automatic-Transfer-Switch/dp/B07F12RDZ2

thanks for the link. That one monitors battery voltage to trigger the switch, a different scenario. I'm looking at this https://www.amazon.com/dp/B09B26ZQT...olid=1H5BNFWWKPDIP&psc=1&ref_=lv_ov_lig_dp_it, a 4-pole to transfer 240v AC L1/L2 and PV-(DC+,DC-). I have one of these, bench testing: https://www.amazon.com/TUQI-Automat...938809&sprefix=AUTO+TRANS,aps,140&sr=8-8&th=1. Haven't decide which to use yet. Am concerned about DC-arcing upon disconnect and the 2nd unit may work better since it's slower given the mechanical motor turning the circuitbreakers. Plus I can replace a couple circuit breakers to DC-rating. Though the first one implies silver contacts and some spiel about magnetic to suppress arcing

I really appreciate your feedback.

You are most welcome, I appreciate the exchanges on this forum, there are much to learn

 

[summit]

Oh, I am also thinking of using a pool timer to control the AC-input to keep the hybrid off most of the time, such as this one: https://www.amazon.com/Suraielec-Di...1663939350&sprefix=pool+timer,aps,229&sr=8-12

 

[Not Aerosmith]

Oh, I am also thinking of using a pool timer to control the AC-input to keep the hybrid off most of the time, such as this one: https://www.amazon.com/Suraielec-Digital-Programmable-Outdoor-Swimming/dp/B09P5X4B4X/ref=sr_1_12?crid=38FYSRACX752T&keywords=pool+timers+outdoor+24+hour&qid=1663939350&sprefix=pool+timer,aps,229&sr=8-12

This timer seems like what I need for the electric water heater. The timer has 7 on/off settings, so I can program it for a couple hours in the morning and couple hour at night.

I appreciate you sharing.

 

[summit]

This timer seems like what I need for the electric water heater. The timer has 7 on/off settings, so I can program it for a couple hours in the morning and couple hour at night.

I appreciate you sharing.

if your water heater needs replacement, consider a heatpump water heater. I installed the early one in 2013, GE GeoSpring, and always ran in heatpump mode. In fact, I've disconnected the two resistive heater elements. It draws only ~350w, obviously more at startup. I hacked the temperature sensor with a dump timer to avoid peak electric pricing hours. Many of the current models have time-of-use built-in now. The added unintended but welcomed benefit is now I can collect of lot of "distilled" water (car washing/house mopping/etc...) and it keeps the basement nice and dry. In fact, the old propane tank was kept as a pre-heater, and added a 300-ft PEX line circulating on timer into the attic. In summer time, I've seem over 100F with my infrared thermometer. Heatpump water should work quite well in warm & moist Panama.
Our last propane refill was in 2013 (house furnace is also electric heatpump)

 

[Not Aerosmith]

if your water heater needs replacement, consider a heatpump water heater. I installed the early one in 2013, GE GeoSpring, and always ran in heatpump mode. In fact, I've disconnected the two resistive heater elements. It draws only ~350w, obviously more at startup. I hacked the temperature sensor with a dump timer to avoid peak electric pricing hours. Many of the current models have time-of-use built-in now. The added unintended but welcomed benefit is now I can collect of lot of "distilled" water (car washing/house mopping/etc...) and it keeps the basement nice and dry. In fact, the old propane tank was kept as a pre-heater, and added a 300-ft PEX line circulating on timer into the attic. In summer time, I've seem over 100F with my infrared thermometer. Heatpump water should work quite well in warm & moist Panama.
Our last propane refill was in 2013 (house furnace is also electric heatpump)

I agree 100% that you have the ideal application for a heat pump water heater. You have eliminated the disadvantages and optimized all the advantages. You needed a new water heater and the basement is the perfect location to take advantage of the cooler dry air.

I just installed a little 30 gallon water heater this year and there was barely enough room to fit in the crowded outside storage building. For me the outside storage building was the best location, since my instantaneous butane water heater was on the other side of the wall and really simplified piping.

My shower has a thermostat that shows the normal incoming water temperature in Panama about 27C or 80F, I like to shower with the water temperature between 35-38C or 95-100F. The little 30 gallon water heater with 4500 watts has no problem providing comfortable showers, since it is basically just a little temperature booster. In USA the incoming water temperature is 20-30F cooler and needs to work harder.

I checked prices and the cost for a small heat pump water heater is about $1500-$2000 about the same as a solar water heater. Since I intend to add more solar panels, I think the money would be best spent on adding solar panels versus changing the water heater.

There is seldom one solution that is right for everyone and I do have a different situation. However, there is no doubt in my mind that the heat pump water heater was the right decision for your family.

 

[summit]

I don't know much about the Sol-Ark's abilities but I think it's asking a lot for an inverter to do this at such a high power level without the safety net of a battery.

perhaps an email to Sol-Ark can shed some insight ? in theory it should be able to operate battery less even. The Sol-Ark would be your only inverter, and sits between your grid & main panel to isolate the grid during outage. You can certain start with a Sol-Ark, then add smallish battery, then add more battery capacity. The minimum battery capacity is to cover the non-sunny duration, overnight/cloudy-days.

I haven't consider the Sol-Ark until this thread, due to the price. The 5kw version is of order $5K, but now with 15kw @ $8K it is getting better. I like that it's US made, presumably better quality and certainly should have better product support. My 2007 Fronius ig3000 is still going strong, knock-on-wood, one minor exception is the screen menu select no longer functionig; hope the generation continues.

 

[Not Aerosmith]

perhaps an email to Sol-Ark can shed some insight ? in theory it should be able to operate battery less even. The Sol-Ark would be your only inverter, and sits between your grid & main panel to isolate the grid during outage. You can certain start with a Sol-Ark, then add smallish battery, then add more battery capacity. The minimum battery capacity is to cover the non-sunny duration, overnight/cloudy-days.

I haven't consider the Sol-Ark until this thread, due to the price. The 5kw version is of order $5K, but now with 15kw @ $8K it is getting better. I like that it's US made, presumably better quality and certainly should have better product support. My 2007 Fronius ig3000 is still going strong, knock-on-wood, one minor exception is the screen menu select no longer functionig; hope the generation continues.

My wife is a professor at the University of Panama and she is going to be teaching until lunch. I intend to use this morning to design a way to convert an existing grid-tie system into a hybrid system. Yesterday, I went through the Sol-Ark schematics, which started me thinking about other possibilities. I have already gone through other manufacturers' manuals, but unfortunately was too focus on their limitations as not a good solution versus on simple work-around solutions. Either I get lucky or I waste the morning, but regardless I will have a little better understanding on what I really need to do.

 

[Not Aerosmith]

I managed to finish a single line drawing of connecting an existing grid-tie system to a new hybrid system. The new hybrid system is connected to the grid and can feed power to the grid from its solar panel or feed power to the house panel during a power outage. The existing GT inverters are not connected to the hybrid system, so they function as normal and the new hybrid inverter doesn't limit or control the existing GT inverters. When the grid is up, the power is fed directly into the house panel and works as before adding the new hybrid inverter.

The point is that there is no reason for the hybrid inverter to trip for overloads or unbalanced loads, since the house panel is getting power from the grid and not through the hybrid inverter. When the grid is up, the hybrid inverter simply feeds it power to the grid with the GT inverters. When there is a power outage, the hybrid inverter is the only power source for the house panel, so it can trip on overloads, etc. You will need to manage your loads during a power outage based on the hybrid inverter limitations and quirks, but not when the grid is available to supply the house load panel.

This is what I have been wanting to accomplish. Now this is my first draft of the concept, so I may or may not have considered everything. I have found reasons and limitations on other manufacturers recommended installations. So I guess fair is fair, and you can find fault with my concept. Thanks in advance for any input.

 

[summit]

First thought: the depicted ATS looks iffy, to be able to handle 200A. It would help to identify the hybrid inverter, as few can do grid-tie feed

 

[Not Aerosmith]

First thought: the depicted ATS looks iffy, to be able to handle 200A. It would help to identify the hybrid inverter, as few can do grid-tie feed

I will answer your question on the new threads that I started this afternoon, Existing Grid-Tie System to Hybrid System.

I just tried and I can't. I had deleted the drawing with 200 amp and substituted a drawing without amperage. It best the ATS be sized as needed per the unique situation. No need to buy 200A, if you need 100A or 400A. I purposely didn't want to show size, because it is a single line drawing for a concept. If someone wants to do something similar, they need to size the inverter, solar panels, batteries, ATS, etc per their application. This concept intends to delete some of the limitations that the hybrid inverter owner manual installation method was causing me.

 

[Ampster]

It would help to identify the hybrid inverter, as few can do grid-tie feed

I would disagree. Most of the Hybrids the OP has been discussing can do grid-tie feed. Because he has considered AC coupling any inverter he decides on will most likely do grid-tie feed and AC coupling, I will respond to his single line diagram on his new post because many of the Hybrids he has been looking at also contain an ATS