Hey guys.

So a thought occurred to me. My plans are still to go with a full Victron/Pylontech ESS system in future, but I cannot get there money wise just yet. I can however potentially buy a 3kva Multi and say 4 panels now. Would this be sufficient to carry at least base load of 500-ish W  during the day?

If not, what is the bare minimum setup that will help save a bit during the day when the sun shines?

9 minutes ago, Minerva10210 said:

3kva Multi ... 4 panels now. Would this be sufficient to carry at least base load of 500-ish W  during the day?

If not, what is the bare minimum setup that will help save a bit during the day when the sun shines?

Multi or Multiplus II?
Yes, depending on the size of the panels and which inverter.
 

9 minutes ago, Minerva10210 said:

If not, what is the bare minimum setup that will help save a bit during the day when the sun shines?

Multiplus II.
RPI and then download the free Venus software and get ESS going.
I would strongly suggest getting a Carlo Gavazzi too. It is wot +-R1k, and get that installed for the savings are in being grid tied feeding all the 4 panels can do, into the house.
Yes, you can also skip it and opt to save +-R500 and use the current sensor but +-R500 more and you have data too. 🙂

23 minutes ago, Minerva10210 said:

If not, what is the bare minimum setup that will help save a bit during the day when the sun shines?

When I started I had what you could call the bare minimum. I had a 1600VA Multi, 4.8kwh battery storage, and 300W of PV (which got upgraded to 450W within a month or so, then 600W, then 900W a year later).

So completely doable. Not sure what battery you are aiming for, but you could start with

1 x 2.4kwh pylontech module (or some cheap lead acids)

1 x 3kva multi

1 x 150/35 MPPT

2 x 300W PV modules

1 x mk3-USB dongle (for configuring the Multi)

Leave the GX device out for now, and play with an Rpi later if you want.

But you're still looking at around 40k-45k for that (assuming 16k for a Pylontech module, 12k for a Multi, 4k for the MPPT, and around R5/watt for the PV, 3k for solar panel framing, around 1k for the mk3-usb, and change for the fuse, cables, etc).

Edit: My prices are out of data and I know it... at the present exchange rate I doubt you'll find a 3k MP-II for just 12k 😞

 

Edited September 18, 20196 yr by plonkster

I am looking at a Multiplus II btw.

Have a Carlo gavazzi already, and have a rpi running Venus. So that's sorted.

Does one need Batts?

34 minutes ago, Minerva10210 said:

Does one need Batts?

Yes. BUT ... if you where me, you could start with a small bank, or 2nd hand bank, and set ESS to Keep Charged thereby keeping the bank happy whilst you feed the house with the power from the panels. And if there is a power failure here or there, having matched the loads to the batts, you can happily power through them.

I did that with 4 x T105RE for years ... only changed when I got a bunch of batteries 2nd hand. 🙂 

 

34 minutes ago, Minerva10210 said:

Have a Carlo gavazzi already, and have a rpi running Venus.

So you are 99% there? What's the problem? 🙂 

Edited September 18, 20196 yr by Guest

15 hours ago, Minerva10210 said:

Does one need Batts?

Yes. The inverter cannot run without them. It doesn't have to be very big. If you use them only during load-shedding (for a modest load), and given that you're talking about a <1kWp solar array, that would work perfectly fine. Only trouble is that even a 80Ah Sabat car battery costs around 1.5k now, so you're in for 6k at the very least and you may get maybe 2 years out of the bank if you use it sparingly.

Second hand batteries is an option too. I ran on second hand batteries for many years.

But perhaps the best option, if you really want to avoid batteries for now, is to look at an AC-tied system. The smallest Fronius you can find for example, is the 1.5kw Galvo (they go for around 22k), but you need to stack at least 4 PV modules in series to drive it.

Or you can go with the Solis units (really really cheap), but not much potential for re-using that in an ESS system in future, which is why I suggest a Fronius.

There's also the Hoymiles micro-inverter. No idea what it is like... has the same lack of future-reuse issue... but for starting with just 600W or so, that might be perfect.

Hi @Minerva10210

I think myself and you are in exactly the same boat.😂 Doing all sorts of financial gymnastics in order to get to a entry level Victron Multiplus II 3kva setup. While I am saving I have decided to read up as much as I can on the whole setup so that when the $$$ arises I can start the installation bit by bit. The DIY part is part of the fun/hell for me so that gotta count for something as well. I have decided to do the whole story over 2020 as a project in phases. Phase 1 will be to sort out the DB...

There is at least a year worth of reading on this forum alone...

@Corné and @Minerva10210 - I have done what you both are doing. 

Options are:
Trawl Gumtree and other sites and buy 2nd hand Victron equipment, with warranties if you can. You save a ton of tom.
Batteries - sometimes you get guys here on the forum that upgrade to Pylontechs, keep an eye out for that.
"Deep Cycle" Leisure batteries can last 5 years on standby, maybe about R1850 per batt for the 12v 100ah. Use then with ESS by setting to "Keep charged".

If you are in the position to buy new:
Buy the inverter first.
MPPT's - the new models can be linked - the VE.Can SmartSolar controller - so you can go smaller MPPT's and then add more later, all working in perfect unison.
Start with the "Deep Cycle" Leisure batteries - batteries are going to be replaced, so cut the first banks cost to the bone.
VenusGX, if you can, gor the Pi route first but get ESS working ASAP. That is where the savings comes from first.
And so forth ... 

Just a tip that works better than manually trawling. Go to ananzi.co.za which searches all of the second hand sites. You can set up a notification that will send you an email with a link when 'victron' or whatever pops up on gumtree, junkmail, olx and a few others.. It is useful as you can get the ad within a few hours of it being put up.

Edited September 20, 20196 yr by DeepBass9