Victron options ?

[Ollie78]

Hi everyone.

I have been looking into solar and battery and after many quotes and options I am leaning towards a Victron and Pylontech solution.
We will have 3 arrays of 4 panels each on south, east, west elevations. Each array is 1740W.
So of the two victron systems I have had quoted they are quite similar apart from one detail which is the MPPT`s.

One company propose 3 x RS 250/70 the theory is that one per array is the most efficient way to do it.
The other company says that one 250/100 is actually fine, thay say doing it this way may be 1 or 2 percent less efficient but for the additional cost it is not worth having 3 separate ones.

I am not sure what to believe here, I am sure both will work but would rather get it right,.

Any insights ?

Ollie

 

[binky]

1 mppt per array is always the best option. Say you have dirt on one panel, the less panels in the string, the less stress on the bypass diodes of the dirty panel, and less panels have their outputs reduced. Dirt has the same affect as shading. When people say 1-2% less efficient they are usually talking theoretical figures produced by software which does not always allow for real world installation problems like seagulls (or shitehawks as they are known down yer!)

 

[bladerunnerpv]

Hi Ollie78,
have you seen victron's MPPT sizing calculator?
https://www.victronenergy.com/mppt-calculator
consult the datasheet for your panels and enter your panel specs and number of panels and it will show what MPPTs match up.

An RS 450/200 has 4 MPPT inputs so could arrange 4panel into each of three, leaving one MPPT free, however you'd need to be certain the startup voltage is low enough or you might no get the output you hope for, I reckon 3 smaller MPPTs is likely to be the way to go, but I don't have a PV system yet so take my thoughts with a pinch of salt.

3 x 250/70 is about 3x£450 excl vat
1 x 450/200 is about £1500 excl vat

What do the quotes' MCS solar generation yields for the different systems indicate ?

You might be able to put microinverters (~£60ea) on all 12 panels and use solaredge with victron, but it adds to the cost
12 x £60 = £720, and a 5or6000W solaredge inverter is about £1000, so about £1700
not sure what else would be needed for the solaredge

[Edit IIRC when I looked at solaredge in EasyPV it seemed like there might be a limit to how many panels on one string - worth checking]

Victron have their own user forum which might be worth a look too

enjoy choosing.

PS did you discount the enphase option ?

 

[binky]

[Edit IIRC when I looked at solaredge in EasyPV it seemed like there might be a limit to how many panels on one string - worth checking]

Solar edge has a max of 16 or 20 per string - can't remember which as it's been a long time since I fitted any. You also have to watch the minimum number of 6/7 optimisers.

 

[Ollie78]

1 mppt per array is always the best option. Say you have dirt on one panel, the less panels in the string, the less stress on the bypass diodes of the dirty panel, and less panels have their outputs reduced. Dirt has the same affect as shading. When people say 1-2% less efficient they are usually talking theoretical figures produced by software which does not always allow for real world installation problems like seagulls (or shitehawks as they are known down yer!)

This was my gut feeling initially but when I spoke to the guy today he thought the aadditional cost not really worth it, I am thinking more over a 25 year period it might be worth the extra. we also have a problem with the sky rats round here.

Hi Ollie78,
have you seen victron's MPPT sizing calculator?
https://www.victronenergy.com/mppt-calculator
consult the datasheet for your panels and enter your panel specs and number of panels and it will show what MPPTs match up.

An RS 450/200 has 4 MPPT inputs so could arrange 4panel into each of three, leaving one MPPT free, however you'd need to be certain the startup voltage is low enough or you might no get the output you hope for, I reckon 3 smaller MPPTs is likely to be the way to go, but I don't have a PV system yet so take my thoughts with a pinch of salt.

3 x 250/70 is about 3x£450 excl vat
1 x 450/200 is about £1500 excl vat

What do the quotes' MCS solar generation yields for the different systems indicate ?

You might be able to put microinverters (~£60ea) on all 12 panels and use solaredge with victron, but it adds to the cost
12 x £60 = £720, and a 5or6000W solaredge inverter is about £1000, so about £1700
not sure what else would be needed for the solaredge

[Edit IIRC when I looked at solaredge in EasyPV it seemed like there might be a limit to how many panels on one string - worth checking]

Victron have their own user forum which might be worth a look too

enjoy choosing.

PS did you discount the enphase option ?

I did have a quick look at that calculator a while back but at the time could make little sense of it and didn`t have all the specs it wanted me to input, I will try again.

All the generation estimates are very similar and I am not sure if they are mostly just worked out on the panel array more than specific components.

I did look into Enphase but it is quite expensive and I am not sure about having more components on the roof than necessary, the reasons I like the victron are because it can cope with the 3 arrays, has very good support, reputation for quality and long operating history, monitoring and control look good and future upgrades of batteries or panels are relatively easy.

Ollie