i think i found my perfect solution

100kwh-hunter

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After 2 years of studying and experimenting i think i found MY golden match....I think, that is.
I would really appreciate your opinion, thoughts, ideas and comments!!!! and every thing else.
End goal: 9 of the inverters and 90 of those panels.
Use two ev cars, home heating(direct into a water tank, so no cells are in this section of the system) electric cooking light ect.

Home heating:
DERNORD Stainless Steel 48v 1500w Electric Immersion Water Heater DC Heating Element|electric element water heater|element water heaterelement heater - AliExpress
with:
110V 220V 12V 24V Digital Temperature Humidity Controller Thermometer Hygrometer Incubator Dehumidifier Thermostat Humidistat DC|Temperature Instruments| - AliExpress
I orderd this one for my tobacco curing room, they have it also for 48v temp cut of to max 25a(first storage:water well 35C, home heating, second storage:shower bath ect 70C)
Inductive cooking will be implemented!
But this is a different threat(2x)

End goal to get rid of all the roberments connections....

PIP-MGX.pdf (mppsolar.com)
This would be theinverter of my choose...(to build up of course......of course i will start with one and every year i will add one or twomore every year!)

Solar pv pannels:
Shop GWL | Solar panel GWL/Sunny Mono 450Wp 72 cells, PERC (ESM-450 Pack 4 pcs)
I think there are a good match, but the amount of panels according to there wp or total Ah deliver gives me some confusion?
Really need some clearance on this and how much panels can i connect to one inverter?????
Please answer this one: hoe much pv i can connect IF they are a match?

Probably not 10 pv panels at each inverter i would like to give them a easy live.
But two times a string of9 inverter string? if this is possible?
Thought and comments on this is also very welcome and appreciated, many many thanks in advance.

The bms is a other subject: 123smart of gwl or batrium? both are stand alone? and both can handle max 255 units(280ah can be one, two 150 = 300 can be one)
Thoughts and advice on this one is also greatly appreciated.
BMS123 Smart Gen3 - Complete Set (4 cells) with Bluetooth 4.0 | shop.GWL.eu

Basically is the inverter and the panels a good match and how much pv can i connect to one inverter, this i still something dont get, yet.....
Thoughts on the bms???

With best regards Igor K, and thanks in advance


https://shop.gwl.eu/Electric-Cars/?cur=1
Will also a different threat!
Best...

PS i am NO vendor or get money of commercial displaying links....
 
Why 9 Inverters? 45KW??? that's an insane amount of Current.
 
jdeadman said:
Why 9 Inverters? 45KW??? that's an insane amount of Current.
needed? with 2 ev's 40 kwh each a day.
Inductive cooking, how much? i dont know. 10kwh? a day?
Heating is now done by wood stove, heating is going to be a separate experiment, how much we need? 5 kwh
The same for warm water...5kwh a day?
The rest 10kwh a day!
Easy life for the inverters? max 75% of there capacity? or even 50%
Solar better 25% to much then 5!% to little?(winter time)

Off grid is the goal! incl water andsewerage.In our longitudeit is a must to have enough storage to have for 5 days ect

Any idea or comment or thought or calculation is welcome
Thanks in advance,Best Igor



But do the panels match the inverters, and how many panels in what configuration can i attach to the inverter.....bms?
 
If you going to spend that much money to go that big i would
1. Dont even think of that kind of equipment. Go with something alot more efficient. You will make that money back in no-time.
2. I would not heat water with electricity. i would either heat water with solar-> water or electricity heaterpump.

Solar to water is more than 80% efficient compare to 20% on solar panels including 20% losses going from panel to battery voltage. . A pump can be up towards 3-5x the energy efficiency as well compare to direct heating.


Do you need to fill the cars within 2 hours? Do you even have that amount of battery that can supply that amount of current? THATS INSANE Thick cables on 48v just as an example. Once again most of the time you can charge over the night and you got 8 hours and do you every night do both cars 100%?

You will need 2000A shunt as an example to the battery bank and those wires :p

I think a redesign is needed from the scratch :)

BMS123 is like the batrium i would say.

You can have around 8 per inverter in series.

Buying one inverter per year in 9 years... Dont expect that inverter to exist in a couple of years.
 
>2. I would not heat water with electricity. i would either heat water with solar-> water or electricity heaterpump.
Was going to comment on this but agree with @Daromer. Hybrid or HeatPump water heaters highly recommended / lighter on power. I have a Rheems 50gal for nearly 2 years now and love it. In heatpump only mode, it maxes out at 450w... and overall power consumption is way less than heating elements. It does take 2-3hrs to completely heat up the 50gal tank in heat-pump mode... but we manage that fine. FYI - these usually haveheating elements for 'high-volum / quick-heat' mode(in case 12 family members all come at once for Xmas and need showers)so you could still use your heating element selection:)
 
It all depends on if you already have grid connection already. There's no reason to get off the grid if you already have the connection. It's easy to reduce your dependence on 90% of your electrical needs that are under 5kw, then for the last 10% where you need high amps like 50kw, stay on the grid. It's fine to use your grid when you run your stove or while supercharging your car at max amps because you need to go on a 300mile trip the next day. Otherwise it's just more practical to stay on the grid and not spend the extra $$$ just for to be able to cover everything.

It's a different situation if you do not have the grid at the moment and the utility says it will cost you $75,000 to bring it to your location. THen you can justify building an off-grid system.
 
not2bme said:
It all depends on if you already have grid connection already. There's no reason to get off the grid if you already have the connection. It's easy to reduce your dependence on 90% of your electrical needs that are under 5kw, then for the last 10% where you need high amps like 50kw, stay on the grid. It's fine to use your grid when you run your stove or while supercharging your car at max amps because you need to go on a 300mile trip the next day. Otherwise it's just more practical to stay on the grid and not spend the extra $$$ just for to be able to cover everything.

It's a different situation if you do not have the grid at the moment and the utility says it will cost you $75,000 to bring it to your location. THen you can justify building an off-grid system.

Absolutely correct! Normal rule of thumb, you will achieve 80% of the result by putting 20% of effort/resources into your project, but for the other 20% missing you need to invest the 4 times more effort to do so. My resort with a monthly 2 MWh of demand is now running 55% off-grid, while only 18kWh/3,5kW storage (=slow night time discharge) is used. The rest is straight away behind the meter usage. An electric car, when charged by solar, will always be charged the slowest possible way if it is not urgent to do faster. First principle is to eliminate users with high power pull, same it was mentioned with the water heating example. In PV applications the most important unit of measurement is not kW, kWh, etc, its is Time. Especially when you are as well talking about seasons. 20% more panels for winter? Forget that! If you live somewhere in mid latitudes as i assume, make that factor 300%.
Your grid connection is your useful helper. Don't sacrifice it, even if money is not an issue to go bigger. Use that extra money for some other projects better, like insulating the house, install an efficient heating system, etc

But to your question:
The only one option to stay within specs with that inverter and those panels is 1 string with 9 panels in series. That gives you 4050Wp per inverter. 2P5S would bring you over the 18A current limit for charging. If you choose 400W panels (but check their max Amps first), you can go for a 2P6S array and get the 5kw out on the charger. More, faster, stronger, etc is not always better as you can see ;)
 
Thanks all for your replays, really appreciated.
I think i was to quick with typing but i will explane my "warm water project" and "home heating" in a different thread.
Tomorrow i will post a link.

Yes we have grid connection.
Mine point of view/thinking.
Yes 9 inverters seems a lot, but solar chargers cost also a lot.
I think i need around 60 pv panels to do what ever i would like to:
Get rid of gas consumption meaning:
Inductive cooking
Home heating and
Warm water.
2 ev's
Home heating and warm water will be on a different thread so i can explain it better, my goof up sorry but thanks for the advice and consurns.
When we are "off the city" gas we can save a 1500 euro a year, but you need to start somewhere? right?

Oke our roberment want to ban all petrol operated cars( what the heck with my old timers...got 7 Cadillac's all v8, the limo has a 9.2 LITRE engine) from 2040....
Lets get a step in front of the roberment:
We can save lets say a minimum of 500 euro each month on petrol(work only), combined with the savings of gas it is 5500 euro a year.
Now that is a month of really hard work(construction is not always sun/dry/warm) and not even including the devaluation of the coin or inflation for over ten years!
And no, we are not going to supercharge our cars, charging time will be max 10 hour and full.( i can charge my car at the constriction site also, even if i would charge my home battery on a trailer....)
But oke we spend all our savings in a system, keep it low: 5000 euro a year:
One pip
8 pv panels
2*16 @ 280ah cells.
This system we can earn back in 3 years because we got rid of the gas.
Do this twice and invest in a ev.
The savings from that will be put into the system ect...
My choise of panels is more based on the wp price per m2(we have max 110m2 death south 18 at wss and 18m2 at ws, i could not find panels under 9a to make it more efficient.
Plus side the inverters will have a easy life with this amount?

I think also when the first three inverters are a fact i Think i will be able to see what the system is short of: panels or cells.
With three inverters we have 15kwh but if we need to add solar panels? 8*3 panels = 24*~400w= 10kwh...Average winter week here: *30-35 hour of sun 300kwh.
Inverer will be cheaper? or a solar charger?
You all got good points, must calculate on this one
What we are going to use? got NO clue, 2 ev's and a wife that loves the oven?
So for every new array of 8 panels a new inverter and some extra cells( go big or go home)
I dont even know if i have those numbers right(low side calculation) sun side i am pretty accurate.
A wild guess on the ev's: 20 kwh each every day? = 500kwh every week, take it rough..
600kwh incl visit mum/dad/family and groceries?



@Daromer,
I fully agree with you on: in ten years from now there will be better inverters and those will no longer exist.
I think when everything is working for three years i will buy some Victrons? i must see how it goes, your advice is always weighing heavy in my calculations!

Oke folks a lot of rambling, i will stop.
Any advice, thought or idea is really appreciated on my idea's
Ideas, advice or any thought aboutpanels inverter chargers and so on, is really appreciated.
For start 3 pips in 3 years with 9*280ah@48v with 24 panels does not seem to be a bad start for over 3 a 4 years?????to build up.
thought ideas comments are welcome.

With best regards Igor K


btw 3*(2*280ah) is 80 kwh is not much for charging 2 ev's?, considering we need sun every other day?
I really got no clue..I think this one I will file (and thus experiment)under: experiment and see????
What was the Latin fraze again???

My wood working shed...380v would be handy....
https://secondlifestorage.com/showthread.php?tid=10173
 
Dont forget 1 year warranty and losses in each step. People forget that and suddenly its alot more expensive!!
 
Check my answer in #4 and the other responses you got.

I dont think your plan holds up :) You need to redesign it.

As i said
Do you charge your cars 100% each day?
If you need that you need 150% capacity in your batteries with that design
You need 200% of what solar can deliver
You will wear out the cells alot quicker with 100% DOD.

24*450w panels wont get you even close to that. I got 16kW of panels and i can best of the days get 100kWh of solar energy. That in useable format is at MOST 80kWh out if you going to charge them.

This is not to discourage you from it but when we talk about this massive amounts we talk about a different dimension.

I got 140kWh of storage and thats planned for 20kwh daily useage. And that is with 16kWp of solar panels ;)

Hope that gives you some sigt into it. So if you plan to use 80kWh per day...
 
Multiple Inverters... I started with 1 AIMS 12,000w and then added a 2nd one as I expanded - so I have 24,000w capability. The problem is that each one has 200w idle consumption (100w per 120v leg)so unless I actually used both of them (all 4 legs)actively my idle consumption takes a hit. In factmy efficiency went from an avg 85% (single inverter) to 78% (both inverters). So Iwound up doing a cross-connect between the 2 distribution panels so i could turn 1 offhave the otherpower both distribution boxesuntil summer when I need both active.Unfortunately I now have amanual managementrequirement to my system that I didn't have before.

The Magna Sineseries havehave multi-inverter efficiency management. The overall controlleractually turns on/off the extra inverters 'as you need the power' automatically... very cool and this helps achieve 95%? efficiency andyou can have up to 6? (see 8:41 in the followingyoutube where the controller has 6 slots). This guy has 3 of them -https://www.youtube.com/watch?v=XO8rJGsyJWY&t=521s to illustrate what I'm saying here. Here's a Magna Sine youtube -https://youtu.be/9lnXT4msP9Q - says up to 4 of them @ 17.6kw of power at 240/120. Perhaps other systems have this kind of feature as well.

Another approach is just to buy a *large* single inverter to start with.

I would considerboth the cumulative idle consumption and'automatic management' capabilities - are you OK with loss of efficiency and/or managing things manually type of thing.
 
Toanswerall said:
Oke redesigning from scratch...
After some searching and some very strong arguments/persecutions, i may add.
It hold also holds firm ground after some calculation for the long term.
I am going with Victron so i wont have those loses, i am open to other idea's!

The inverter side: Victron Phoenix 48/3000 230V for parallel connection or the 48/5000.
I will of course keep the dod between 20% and 90% regarding lifepo4 specs.
You wont believe: but this forum has learned me a thing or two....
@offgrid i will check the link this week.

daromer
Check my answer in #4 and the other responses you got.
I did thoroughly, that is why a late replay, exceptthe warm water part!!!
I dont think your plan holds up :) You need to redesign it.
Busy with it....

As i said
Do you charge your cars 100% each day?
Probablynot, i plan to buy or make a car that is able to do 150% of living/work distance.
Heating and airco would be nice, but you can open the windows and wear a coat when driving home or to work?!?!?
In my case no problem i work outside, my better half, i would not like it.
Again i have no clue how much they will consume.

If you need that you need 150% capacity in your batteries with that design.
I had 200% in my mind to survive a cloudy day and give my cells a easy life, knowing myself: i probablywill keep adding cells just for fun and games, most importantto give my cells a easy life, we dont need to drive two cars 15 years from now every day 150km each....

You need 200% of what solar can deliver.
IFi can place 200% on pv panels! Big IF.....

You will wear out the cells alot quicker with 100% DOD.
The Dod i am planning to use is: from 20% to 80%...Probably15 to 90, I must take a look at the chardbetter.

24*450w panels wont get you even close to that. I got 16kW of panels and i can best of the days get 100kWh of solar energy. That in useable format is at MOST 80kWh out if you going to charge them.
Quick calculation:you have ~100-110m2 on roof surface covert with pv? i have total usable surface of 240m2, 145m2 death south
You are also a 1000km above me, i think i have more sun hours a day?The Netherlands to Sweden? ok Sweden is a very long country compared to Holland. i dont know exactly where you are located?
I remember a old joke/truth that mySwedish friendstold me: Every Swedish man knows the width of the forest, but no Swedish man knows the depth/lengthof the forest!
But those are fine numbers to deal with from my corner!

This is not to discourage you from it but when we talk about this massive amounts we talk about a different dimension.
Direct me to this dimensionplease.

I got 140kWh of storage and thats planned for 20kwh daily useage. And that is with 16kWp of solar panels ;)
WOW 7x more.....if my estiment is holding some ground...7x60-7x80....420kwh to 560kwh
I accumulated106!kwhsold some and give away some.....106kwh, i still regretit....oke due to a "live event"....
Get over it and move on...


Hope that gives you some sigt into it. So if you plan to use 80kWh per day...
I really dont have a clue what we are going to use a day....40kwh? perhaps 10kwh????perhaps 100kwh.....
2 ev's: each 1 car 120km a day and one between 40 and 160km a day.....
Airco with power that is left over, home heating is a other project....
Inductive cooking....got no clue.
Rest of the house? 3kwh a day max 5.
My wood machinery....when i use....when....2.5kw-5kwan hour operating.
.....

Anyway:
I was cracking some numbers today with the available panels and the solar charger from Victron....
costs per panel
per panel: 38,5v, 9.5a, 285wp, 60 euro, 1.6m2m2
per panel: 40.0v, 10a, 310wp, 65 euro, 1.6m2
per panel: 41.3v, 10.3a, 330wp, 85 euro 1.7m2
per panel 49.8v, 11.8a, 450wp, 90 euro 2.2m2


With all available solar chargers on 150v and two 250v
35a,45a,60a,70a and the 250/60...
Those two are popping out:
pv panels / solar charger
wp s p total w / 150v/45a
0.285 3 3 2,565 /max 2.6kw
and:
wp s p total w/150v/70a
0.33 3 4 3.96 / max 4kw

Based on the most w per m2
First one 210 euro for 1kwh

To bad i can not put my exls into this answer, sorry.

But i was keeping it on the save side, not exceeding the v and the amount of nominal watts the chargers could have:
Could it do harm if i would use a bit more wp?
Then the numbers would chance quite a bit in matters of w/price per m2
If i could 10% above the w of the solar charger...

My plan of attack....Keep expending till the roof is full enough inverters to get us a day around....energy storage, just adding.
First part:
inverter, charger, pv and some cells.
second:
charger, pv and cells.
third:
inverter and cells.
At this point i must see what we are short of.

A lot of rambling again....a lot, I hope it will make some sence...
Thanks for reading and your thoughts on this, btw to get rid off the grid is a dream i know, even 50% would be very nice.
Gas and petrol is the game, at least to try.......

Thanks in advance, best Igor
 
The first and most important tihng you should do when you want to use solar to power your home is to reduce your current useage. I reduced mine with over 45% starting..

Btw i live in southern sweden so during summer i get decens sun for sure! But during winter we talk about 5% compare to summer ;)
 
Regarding the house, everything is already energy aa+ and led's.
That amount usage is almost nothing compared to the usage of a ev and electric cooking.
Oke we can go cheaper...place the cooler in the shed with the door open, it is below 7C. :cool:
We could light every day some candles. :blush:
We dont even have a tv, only one laptop. :D
Walking to the next grocerystory(5km away) :s
Not even 100 years ago most did not have electric light and Cadillac made the first ev in 1914 or something, first electric cooler around 1930 ect.

Per roof area i figured out some Victron solar chargers as mentioned before, incl the panels.
And what dimension where you speaking of? Not even Victron?Other brand/system?

To start with a Phoenix inverter suited for parallel 48/3000 or the 48/5000 seems to be a good start incl a 10kw falifax switch?
Regarding the solar chargers i kept every value below the max of the charger.
Could it do harm if i would oversize a little at the max nominal watt?

150/45 solar charger seems the best choose for my first victim roof, max usable 18m2
Max150v, max45a, max 2,6kw, cost:550E
With the available panels:

Wp per pv/ in serie/ in paralel/ voc /harvest p-h/ cost per m2/total m2
285 3 3 115,5 2,565 210 14,4
310 3 3 120 2,790 193 14,4
330 3 3 124,5 2,970 181 15,3
450 3 2 150 2,700 200 13,2

With the 285wp panels i am well below the max v and max w
With the 310wp panels i am a bit over the max w of the charger.
With the 330wp i am pretty much over the charger max
Regarding the 450wp the voc is a little to high especially when it is getting colder
I think the 330wp would be the best choise? not even cost wise but harvest wise?

What are your thoughts on those ones incl the inverter?
Thanks in advance, best Igor
 
With your panel choice, going with the most common size the local solar industry is using now may save you money.
Also consider what panel replacement cost might be if there is damage, eg from a hail storm or you drop one during install.
Voc must be "cold day" heavy cloud to sudden full sun because this is what will be the highest.
 
Your project and idea to go-off grid is close to where I am at the moment.....

Been working through the details (for the past year) on going to a battery setup somewhere around 80V-110V, which will raise a few WTF reactions here.

The reasons for considering going above 48V for me is a bit of a list and a little more complicated for my particular situation, although I'm not 100% convinced yet even after a year of research.

The lost energy cost of idle losses from the 12kW units over 10 years can be more than the original cost of the inverter depending on your power price, so idle losses, especially winter time, can become a really critical factor.

Multiple smaller 3-5kW units in parallel I'm not sure how well they are syncronised for large load connection and also end up with higher no-load idle losses. Hooking up an 11kV charger for an EV to 3x5kW inverters in parallel ? The parallel units are also all HF based and prevent back-feeding options. From memory I seeem to recall that 20kW (4x parallel) will still only support about 6kW load switching so 11kV EV charger, magic smoke..

I have been experimenting with a smaller remote islanded grid setup with 4kW solar, 700W wind, 20kWh of battery and 1kW+5kW inverters to work out some of the practicalities and realities of the setup.

Also, off-grid true island mini-grid is not always as simple as it first sounds because I have had issues with harmonics on the grid because the inverter can only cope with a limited amount of distortion and harmonics. For example the wind 1kW grid-tie inverter would disconnect briefly due to loss of waveform tracking when a switch mode power supply is plugged into the mini-grid. Not necessarily an issue that most would encounter.

I'm considering building the inverter from a standard(ish) board and separate multiple toroidal transformers like my existing builds so I can then effectively choose the working voltage which is then closer to the Vmp of the solar ouput and this allows some of the solar to effectively connect directly to the battery PWM style and some to back feed via the mini-grid (using grid tie solar inverter) through the main inverter.


Heating is wood and if your ok with a chainsaw and a bit of excersize you will never beat that option.

Heating air or water on a 1:1 basis with resistive elements will go the way of the incandesent light bulb.

Solar water heating an option unless space for panels is a critical factor then PV with a battery wins..

E550 for 2.6kW of solar charging capacity is just not economical and only makes sense if you are space constrained on area for PV panels. E550 can buy you 2.5kW of solar at your pricing of E65 for 310W panels and then use a very cheap PWM switch control with 2 series setup. For a controller to cost nearly the same as the PV panels how can it be economical on a small scale ?

Also, 1695mm vs 2000mm panels can be a very big difference when playing tetris on your roof layout.
 
Regarding the house, everything is already energy aa+ and led's.
That amount usage is almost nothing compared to the usage of a ev and electric cooking.
Oke we can go cheaper...place the cooler in the shed with the door open, it is below 7C. :cool:
We could light every day some candles. 😊
We dont even have a tv, only one laptop. :D
Walking to the next grocerystory(5km away) :s
Not even 100 years ago most did not have electric light and Cadillac made the first ev in 1914 or something, first electric cooler around 1930 ect.

Per roof area i figured out some Victron solar chargers as mentioned before, incl the panels.
And what dimension where you speaking of? Not even Victron?Other brand/system?

To start with a Phoenix inverter suited for parallel 48/3000 or the 48/5000 seems to be a good start incl a 10kw falifax switch?
Regarding the solar chargers i kept every value below the max of the charger.
Could it do harm if i would oversize a little at the max nominal watt?

150/45 solar charger seems the best choose for my first victim roof, max usable 18m2
Max150v, max45a, max 2,6kw, cost:550E
With the available panels:

Wp per pv/ in serie/ in paralel/ voc /harvest p-h/ cost per m2/total m2
285 3 3 115,5 2,565 210 14,4
310 3 3 120 2,790 193 14,4
330 3 3 124,5 2,970 181 15,3
450 3 2 150 2,700 200 13,2

With the 285wp panels i am well below the max v and max w
With the 310wp panels i am a bit over the max w of the charger.
With the 330wp i am pretty much over the charger max
Regarding the 450wp the voc is a little to high especially when it is getting colder
I think the 330wp would be the best choise? not even cost wise but harvest wise?

What are your thoughts on those ones incl the inverter?
Thanks in advance, best Igor

Hello Igor

I have victron smartsolar 150/85 max 4900w

In my case i have 24x 225w (3 series/ 8 parallel )panels is 5400w power and there was no problem yet.
Victron mentions up to 30% oversize of solar panels.

Do not exceed the input voltage of pv damages the mppt . I have panel with 36.5v open voltage in series 3x exceeds 115v at -5C

mppt oversize.png


You can download victronconnect to your phone. the app has a demo option and you can play around with the settings a bit.
Smartsolar which connect via bluetooth to phone and very easy and fast setting. ( Previously i had epever mppt sync with pc- mppt desperate)
Victron has a very fast mppt and comparison with epever, victron works 20w-30w more power per panel.

On summer days I have it set mppt to 80A charging.
Maybe if something helps you;)

Best Regard Zvonko
 
I'm having a hard time following this thread, but would like to suggest to the OP that he seriously look into solar hot water panels. It is pretty easy to do a simple drain-back system, and many components can be DIY. The hot water can provide heating, dish washing, showers, etc. Much more efficient than PV. Take part of the load off your PV system requirement.

You can get DC pumps to run direct off a small solar panel, so if the sun is shining you get hot water, with no conversion loses. When the sun stops, the water drains back. Easy. You need a storage tank, which can be DIY too. Bigger is better. Insulate lines carefully.

I ripped out our forced air furnaces, and converted to radiant heat with a gas fired boiler. Bought solar hot water panels that will produce on average about 54,000 BTU, and am building the racking now while the outside temps are ludicrously cold. The panels will go up in about 3 months and start making hot water. They can max out at 96000 BTU total. Our plan is to greatly increase our tank storage volume, have it heavily insulated, and use it to circulate tempered water through our radiant system via the water to water heat exchanger. Right now we have a 100 gallon tank. I did all the piping myself mainly with 2" copper. The lines to the solar panel location are 1". Pumps have gotten highly efficient, and are easily backed up with PV and batteries. Our entire system (boiler/pumps/zone valves/controls/thermostats) have a total load of about 600 watts if they are all on at the same time. (Which they aren't very often) Most of the time, our system uses about 300 watts. Right now the system includes 2 older pumps we can replace with ones that run at an average of about 14 watts each, which will lower our consumption another 120 watts. I realize you don't want gas boilers, but that doesn't mean you cannot do solar hot water.

Of course, we are doing PV, and massive battery back-up, but solar hot water is an important part of our overall plan. There are also tax credits here in the US that help with overall costs. President Biden extended the tax credits for an additional 2 years.
 
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