Hey everyone

 

I stay in a house that uses around 30 units electricity on average per day obviously goes up when using aircon/tumble drier/ oven etc. 
 

I am looking for a solar solution that will reduce my bill but also help with loadshedding. My budget is limited tho. I have around 35 lights around my house/garden/ driveway walls and outside wall which I like and what to keep due to the fact that everything is nice and lit up and it is a plus for safety. 
 

I want to leave my electric oven (top is gas) on grid as well as my aircons. Should I change my Geyser to a 2kw element and leave that on the grid or add to my inverter on a timer? 
 

Should I go 5KVA inverter or 8KVA?   And which one? I was told to get sunsynk but friends told me to go for RCT Axpert  2 and another told me to go Kodak. 
 

I have an electric geyser and my budget doesn’t allow to change to solar geyser and I need to get something for loadshedding so that is why I am planning the above. 
 

I would like to start with 10 KWh battery but I am sure budget will limit to 5kWh to start off with. 
 

Any advice/ideas?

 

Thanks in advance 

Hi Eldred, 

What is your budget? 

I would get the 8kw Sunsynk with as many panels as you can afford and enough battery power to get you through 4hrs of load shedding when you have no solar.

It sounds like your load-shedding load will be relatively low but you should measure your load in the evenings to be surer of what your usage is. I would look for a battery system that can easily be upgraded. You should take note of the max amount of power the battery can supply the inverter, if your battery can only supply 5kw of power that is going to be the max that your inverter can supply. 

I would connect your oven/aircons etc to the non-essential side of the inverter so you can still run them from Solar when you have extra power but they won't kill your battery when you have load shedding.  

Would suggest putting smart switches onto your geyser so you can have them only switching on during the daytime and if you get the 8kw Sunsynk would leave the 3kw element in it. Would put the money into more panels for your inverter rather than a solar geyser. 

Thanks for the response. I am in the process of saving some money. Managed to save about 100K so far. So depending on when I do take the plunge will depend on my budget at that point. 

15 hours ago, Eldred said:

Thanks for the response. I am in the process of saving some money. Managed to save about 100K so far. So depending on when I do take the plunge will depend on my budget at that point. 

Great info from Sc00bs. Take note of the fact that you can already get a LS solution in place by using a Sunsynk plus battery without the solar panels. Charge battery from the grid. This will fit your budget.

Eldred, I started with that amount of money with phase 1 last year - 8kw inverter, 12 Panels and one battery. I swopped my 4kw geyser element for a 3kw and ran my geyser from 10:00 in the morning un summer. My take on it was I would rather spend the money for solar geyser on more pv and batteries later. 

 

 

My question is do I go with a sunsynk or Axpert like a Kodak or RCT. Do I need the 8 KVA. 
 

I have read that when the sunsynk 5 KVA is connected to the grid it can handle a load of 8000W. And when it is loadshedding it is limited to 5000W. 
 

I’ve heard that if you overload the off grid inverter it alarms and trips. 
 

I want something that if I overload it, it just pulls the balance from the grid. 
 

I am not planning of going completely off grid. So I am very confused on what to do. So many installers and distributors have their own opinion. One saying one thing and another something else. 

Edited May 30, 20224 yr by Eldred

Sunsync is very popular. It does everything and a bit more, but it costs more money. Imho it is value for money. It just works.

Axpert type inverters are a lot cheaper, but they are limited on how they allow you to use the power. I see plenty people struggling with the limitations, sure there are people that have figured out ways to make it work for them. Eg my dad manually monitors and switches his axpert unit, he calls it part of being off-grid.

You could install a 5KW and let it pull the balance from the grid, but you will be limited once loadshedding hits.  I use about 10 units per day and I got the 8KW Deye unit( which is pretty much the same thing) with plans to go off-grid if they start charging me a monthly charge to be connected to the grid. When monitoring my power I had spikes up to 6KW (when you cook and boil the kettle at the same time). I use a heat pump for hot water.

 

Definitely Sunsynk by far, especially if you still want/need access to the grid.

I unfortunately cannot afford the 8kva sunsynk. But the price for a 5Kva sunsynk and 8kva axpert type is basically the same according to quotes I got. For me it is not a thing about going off grid completely. I want to have a backup in loadshedding and also reduce electricity bill. I am also willing to cut down usage during loadshedding to not overload the system and make my batteries last. 

4 minutes ago, Eldred said:

I unfortunately cannot afford the 8kva sunsynk. But the price for a 5Kva sunsynk and 8kva axpert type is basically the same according to quotes I got. For me it is not a thing about going off grid completely. I want to have a backup in loadshedding and also reduce electricity bill. I am also willing to cut down usage during loadshedding to not overload the system and make my batteries last. 

Personally, I would rather have a 5kVa Sunsynk than an axpert. (But you can also look at Deye, which is the Sunsynk with different firmware for a bit less)

10 hours ago, Eldred said:

I unfortunately cannot afford the 8kva sunsynk. But the price for a 5Kva sunsynk and 8kva axpert type is basically the same according to quotes I got. For me it is not a thing about going off grid completely. I want to have a backup in loadshedding and also reduce electricity bill. I am also willing to cut down usage during loadshedding to not overload the system and make my batteries last. 

Funny that you find the 5kw and 8kw closely matched. The difference at on line outlets are about R8000.

I am with P1000 on this one for the Sunsynk/Deye

Edited June 9, 20224 yr by Scorp007

Hi Eldred.

I believe that your current budget allows for addressing your needs. (Where are you located, if I may ask? Another member may be able to advise regarding local options.)

Prices have changed since last year, but I'll mention figures to illustrate. Sunsynk 5kW (R21k) vs 8kW (R31k). Deye is similar to Synsynk, but slightly cheaper to purchase (about R3k for 5kW model). If pressed for price and you only want to buy once, learn once, set up once, consider buying the 8kW Deye. (Having suffered with an Axpert before, I'd avoid it myself.) If you have sufficient solar collection now, you could add panels later, budget permitting. Remember to plan for that capacity and mounting now and only pay once for hardware, and you could possibly install additional panels yourself and simply connect. In the meantime you have a reasonable "free" solar supplemental input and back-up during loadshedding. My present consumption is about 30kWh per day. I chose the 5kW inverter based on current need, but am aware that long term needs may differ, although children are now leaving home. However, I installed a higher power cable to connect inverter to DB for future-proofing.

I bought 4kW of panels to add to my previous panels (conveniently now on 2 strings). Even if mounted flat on roof, remember to budget for mountings, which add up fast. My roof pitch is 15 degrees, so summer yield is high (>5kW). Last week I changed the pitch of the old panels to about 40-45 degrees and am now receiving 400W more at peak (on 1.6kW nameplate rating, that is significant). My newer panels may see a similar adjustment soon, but I am prepared to adjust seasonally.

I opted to have the electric stove connection bypass the inverter completely. (The top runs on gas.) The geyser has a 2kW element, although I have solar prefeed (saving 50%). This allows electric heating by day using solar at no/little cost. (These options add up, allowing you maximum draw from solar when available, otherwise it has to be stored in battery or lost. In winter, with shorter days, it could become a significant portion if managed correctly.) You are able to manage battery levels to reserve a predetermined charge for the event that loadshedding strikes from 6-8am, provided your battery capacity is sufficient to supply your household's morning peak. Which brings us to batteries. I opted for 2*5kW Li-ion batteries, which last well through warm, shorter summer nights. However, using timed charge limits overnight to ensure 2kWh available power through peak demand results in municipal power usage during winter. (Monthly usage is now about 200 kWh in winter, almost none is summer.) One 5kWh battery is sufficient for 2.5h of loadshedding, day or night (i.e. 4kWh use from fully charged, but just don't keep it there if you want it to last).

I installed the rooftop panels, inverter and local isolation/fuses myself, saving on installation fees. Don't hesitate to renegotiate cost with the installer if they only connect components. Although prices have increased, if you can accept 4kWh back-up with 5kW inverter, then you should still make it with R100k (installation, rewiring DB, switches, fuses, mountings and large components).

Flexibility depends on priorities, and remember to shop around for prices once you have decided which option/model suits you. I stay in a 'dorpie' with a reputable and willing electrical store, and knowing that I can count on their support for planning, sizing and purchasing hardware such as inverter, panels, batteries, fuses, etc. provides ease of mind.

I hope you can settle your needs and wants into a reasonable specification (or two) soon and get your project going.

Edited June 16, 20224 yr by LoodPyp

Top Post!!

I am from Port Elizabeth. 
 

Quotes I got:

Sunsynk 8kva R41400

Sunsynk 5kva R25400

RCT Axpert 8kva R25156

Anther quote RCT MX2 Axpert R22000

 

So many installers advised me to go Axpert due to my budget and then go for the 8kva. They say the sunsynk is very nice if you can afford it.

 

 

 

https://powerforum-store.co.za/collections/featured-products/products/copy-of-sunsynk-8kw-1p-hybrid-pv-inverter-48v

R 35,161.25

Hi folks

The Sunsynk/Deye inverters are bi-directional hybrid inverters (which terminology is often misused) in that they can be configured to feed excess PV energy back to the grid side (or non-essential-load side), much like a grid-tie inverter, simultaneously with powering the load output and charging the battery. A small CT installed at the incoming grid/muni connection allows the inverter to back off and not back-feed into the grid. This is what I understand, but have no direct experience of, so be gentle with me if I have it wrong.

IMHO this is a game changing feature. It means that you can power your geyser with excess PV energy, without placing it on the essential-load side of the inverter. Hence it will never draw power from your battery, or load the output of the inverter, and will draw the balance of energy required to heat the water from the grid.

So Eldred .. If you have one of these inverters and PV panels then you have all you will need to heat you geyser economically .. no need for a separate solar-thermal/pumped system, PV geyser system, heat-pump or whatever. Effectively the battery is just for load-shedding. Rather buy more panels, as and when you need/can afford them.
What is seldom if ever mentioned on this forum is that various municipalities charge a monthly levy just for the privilege of having an electrical connection (which can be substantial, and can never be cancelled), and even a monthly levy for a grid-tie connection (in-feed tariff applicable to read the meter .. also substantial), which fees all skew the financial model for your system. For this reason, so many members of this forum recommend that you stay on the grid, and don't apply for the in-feed facility.

I don't have such a system, and sure wish I did. There is so much scope to play.

Can afford either 8kva RCT of 5KVA sunsynk with a 5kwh battery and 3.5kwh panels. That is my dilemma that I am sitting with. Get the 8kva and run everything off inverter and run geyser and pool pump on timers for daytime use with solar and use battery as backup and try and cycle it daily to 50% and keep the rest for loadshedding. Or get 5kva and add everything except oven/geyser/pool pump and then export solar to non-essentials. Either way with loadshedding I will have to make sure to reduce my load and usage due to small battery size. 

46 minutes ago, Eldred said:

Can afford either 8kva RCT of 5KVA sunsynk with a 5kwh battery and 3.5kwh panels. That is my dilemma that I am sitting with. Get the 8kva and run everything off inverter and run geyser and pool pump on timers for daytime use with solar and use battery as backup and try and cycle it daily to 50% and keep the rest for loadshedding. Or get 5kva and add everything except oven/geyser/pool pump and then export solar to non-essentials. Either way with loadshedding I will have to make sure to reduce my load and usage due to small battery size. 

Because the Sunsynk is such a great kit even if you go for the 5kw and you find the essential side does not fit well with your lifestyle you can always add a 2nd one.  Coming from a technical side I would prefer 2x5kw instead of 1x8kw.  If the 8kw needs repairs the whole system is down and with 2x5kw you still have a 50% system working while waiting for the inverter to get fixed.

I’ve just gone through this whole exercise on what inverter, batteries, panels , geyser timing and so on. I also have a crypto mining rig. 
 

bottom line is that this doesn’t need to be done all at once, I would rather get the right inverter and battery or batteries first and set yourself up for load shedding. You in the meantime can get your electrical in house sorted out for essentials and non essentials and then as you get more funds start adding one panel at a time until you get to the point that you have enough panels. 
 

for me, the sunsynk was a no brainer, most people use them and almost everyone suggested you should use them. There’s obviously a lot of reasons why…
 

if you do this exercise correctly then you only going to do it once, if you get inferior products you might be redoing your whole installation twice. At the end of the day it’s all up to you but just do it right the first time even if it takes you longer to complete rather than wasting money. 
 

eg, my 8kw sunsynk arrived yesterday, super excited but I have nothing else. I haven’t decided on what batteries yet but I was 100% sure of the sunsynk, that’s why I’ve already bought it. 
 

Edited June 16, 20224 yr by Derek Ramos

Would a 5kva limit me in the sense that I will overload it often? Of with grid being on will I just use pull extra needed from grid. Example load is sitting at 3 or 4 kw and someone puts on hairdryer or tumble drier and load pops to 6 or 7 kw, will the 5kva trip or pull extra from grid? I know when grid is down it will trip. But again when loadshedding hits I want to make sure heavy load items are off to preserve battery. 
 

I understand to get it right from the start, but to get 8kva sunsynk and a battery without panels defeats my goal in saving on my bill. I don’t know how soon I will have another 30k for panels. That is why I am going for a system with panels and that is why I am limited by my budget. Paying 100k just for a loadshedding solution is not worth it for me. Some people might be able to save 30k in a couple of months, I cannot unfortunately. 
 

Spending 100k I want to make sure of all my facts. It is a big spend for me. 

48 minutes ago, Eldred said:

Would a 5kva limit me in the sense that I will overload it often? Of with grid being on will I just use pull extra needed from grid. Example load is sitting at 3 or 4 kw and someone puts on hairdryer or tumble drier and load pops to 6 or 7 kw, will the 5kva trip or pull extra from grid? I know when grid is down it will trip. But again when loadshedding hits I want to make sure heavy load items are off to preserve battery. 
 

I understand to get it right from the start, but to get 8kva sunsynk and a battery without panels defeats my goal in saving on my bill. I don’t know how soon I will have another 30k for panels. That is why I am going for a system with panels and that is why I am limited by my budget. Paying 100k just for a loadshedding solution is not worth it for me. Some people might be able to save 30k in a couple of months, I cannot unfortunately. 
 

Spending 100k I want to make sure of all my facts. It is a big spend for me. 

AFAIK with the bypass at 35A for the 5kw Sunsynk it will give you about 8kW of power when the grid is on.

On 2022/05/30 at 2:31 PM, Eldred said:

My question is do I go with a sunsynk or Axpert like a Kodak or RCT. Do I need the 8 KVA. 
 

I have read that when the sunsynk 5 KVA is connected to the grid it can handle a load of 8000W. And when it is loadshedding it is limited to 5000W. 
 

I’ve heard that if you overload the off grid inverter it alarms and trips. 
 

I want something that if I overload it, it just pulls the balance from the grid. 
 

I am not planning of going completely off grid. So I am very confused on what to do. So many installers and distributors have their own opinion. One saying one thing and another something else. 

Apart from the rather obvious maximum amounts of DC power the Sunsynk 5kw & 8kw inverters can provide (5kw & 8kw 🙂 ) , the other thing that you need to be conscious of is the amount of "pass thru" power that they can handle. 

Pass Thru power refers to power coming thru the essential connection on the inverter 

Sunsynk 5kw - max passthru is 35a which at 230V is around 8kw. This means for example that if you are pulling 7kw for example, the max it can pull from your solar/batteries is 5kw and the other 2kw it will pull from the grid, up to a maximum of 8kw (somewhat less in my experience) at which point the inverter will trip out. It might pull all 8kw from the grid depending on your settings but it will still trip out. 

Sunsynk 8kw  - max passthru is approx 12kw 

There is also a "non-essential" connection on the inverter which you can think of as almost a grid-tie connection. You have settings in the inverter that you can configure as to when the inverter will back feed power to the non-essential items in your house. Typically people connect ovens etc to the non-essential side.  These items do not add to the "pass thru" current total. I am not sure if non-essential items can be powered when you are off grid, perhaps someone who uses that feature can comment.

From my understanding the main difference between the Sunsynk & the Axpert inverters (most of the AXpwert's in any case) is that the AXpert inverters cannot blend Inverter /Eskom power so if the inverter is unable to power your load for whatever reason, it is unable to blend the power and just switches your full load back to Eskom. 

If you have the money available I would definitely recommend getting a Sunsynk. 

 

 

 

 

 

 

The problem with the Axpert that cannot blend their output with grid is when you try to exceed the 5kw to load circuits it would trip and needs manual intervention to switch the thermal device on. One can see it as a pass through limited to 5kw. This 5kw comes via the grid input.

This is how I have seen it working on the older Axperts mine included.

So I have a friend with a RCT axpert. He explained that his inverter blends Eskom and PV power fine without any issues. His inverter is the 8Kva hybrid model. 
 

Do the inverters trip once you overload or does it go into bypass where it basically just uses Eskom?

5 minutes ago, Eldred said:

He explained that his inverter blends Eskom and PV power fine without any issues.

The degree to which they can blend seemingly differs based on model and firmware (and if clone). But if you look at the amount of posts for people with issues based on type of inverter, the ranking is quite clear. I know a number of installers that will never (again) install an Axpert purely because of the amount of support associated...