Would a system like this work to beat load shedding?

[Basil Katakuzinos]

 

Just out of curiosity, would a system like this work as a 'more' affordable load shedding solution for someone without a massive budget? 

With batteries connected in 2S2P to cater to the 24V inverter.

 

[Basil Katakuzinos]

How do the hubbles handle being connected in Series/Paralell. Are battery balancers required?

[hoohloc]

why not get a 48v inverter @ R6850 and Pylontec US3000C @ R17350? Then you don't have to worry about how to wire the batteries in Series/parallel. US3000C is a 3.5Kw battery and will match your 3kw inverter perfectly. Not sure about the Kodak though, have a look at Growartt SPF3000TL-48

[BritishRacingGreen]

1 hour ago, 87 Dream said:

Hi Basil, 

I cant talk much on the pylontech product that @hoohlocrecommends above, however, what i can say is that given the costs I would always go for the 48V system. The 24V system will suffer from a lot of heat build up. The lower the battery and inverter voltage as in 24V Vs 48V the lower voltage cables will need to carry a lot of Amps to carry the same wattage. The 48V in the longer term is just safer with less heat and needs not as thick cabling.

The other problems faced is that, some 12V LiFePo4 budget batteries cannot just be wired in series or parallel to make up a system voltage. The internal BMSs sometimes have limitations on these. Im not saying that the Hubble falls into this category, Im just saying that the tech manual that is supplied with the battery will need to be double checked before making the purchase with this in mind. I have seen the Mecer LiFePo4 batteries not with stand the exact same setup you are trying to establish. Then you have a big mess and will need to sell the cells on to salvage some cash.

My minimum recommendations on such a system is at least, 5kW inverter at 48V and at least a 16s LiFePo4 cells arrangement. I say 16s because the cell voltage is advertised as 51.2V and the 15s as a 48V nominal voltage. I say this for my own reasons but rather buy smartly than on budget alone and end up in a mess down route.

87

True .  3kw borders on small appliance ups needs.  5kw good value , value alone is not good in solar ,  as you cannot really scale upwards without spendings lots of money.  

Max 7.2 kW  inverter,  5kw solar panels , and one  lifepo4 48 6kw pack  I'd say you future  proofing yourself.  Money well spent , I have underestimated the utmost importance entering the solar market, and if you stay in Germiston as I do , you can see it on daily basis. Load shedding is the least of our worries,  it's the p#ss poor quality  of service , and the high rates.

Oh and I believe you and Sarel are right re Griff tie and feed. It's a pipe dream at the moment.

Re batteries: With pylontech you get  out of box functionality, but I am glad I went the DIY LFP .  It's a game changer when you want lots of value. 

 

[Guest Sarel]

I have just uploaded a new post where I modeled a house with 6 panels and a 5kW inverter and one battery in “New solar planning guide” on here. Do not want to hijack this. It may prove insightful and helpful for this very purpose.

[TimCam]

4 hours ago, hoohloc said:

why not get a 48v inverter @ R6850 and Pylontec US3000C @ R17350? Then you don't have to worry about how to wire the batteries in Series/parallel. US3000C is a 3.5Kw battery and will match your 3kw inverter perfectly. Not sure about the Kodak though, have a look at Growartt SPF3000TL-48

If your budget is limited to between R25k - R30K, then this slight upgrade "hoohloc" suggested will be good for now. Don't bother with 24V systems in this price range, they are for  R4000.00 UPS's, not whole house systems. As far as I can remember, Pylontec batteries are .5C, and therefor during load-shedding will only supply 1.75 Kw.

What I've done is install a buzzer through a 240V relay to let the family know when municipal power is off, so as not to drain the batteries unnecessarily.

 

[ianm]

For a bit more you could maybe consider an installation like this:

5 kW VMIII +  Hubble AM-2

 

It is a nicely matched system as the AM-2 is 5.5 kWh (1C), so the inverter is able to supply the full 5kW (more than enough to boil the kettle).

[hoohloc]

9 hours ago, ianm said:

For a bit more you could maybe consider an installation like this:

5 kW VMIII +  Hubble AM-2

 

It is a nicely matched system as the AM-2 is 5.5 kWh (1C), so the inverter is able to supply the full 5kW (more than enough to boil the kettle).

I doubt you can get all that with a budget of R25k. The Hubble battery is already R26k alone, R1k over budget and you still need to get an inverter and bits and bobs. The 4.6Kw kodac inverter is around R19k. The OP wanted a budget friendly solution, lets not scare him into thinking that budget friendly does not exist when he can get a good solution for less than R30k. 3Kw inverter will work just fine if the DB is split into essential and non essential. Kitchen plugs, except for the fridge plug, can all be wired to non essential and no worries about someone switching the kettle or microwave while there is loadshedding.  You can power all the lights, TV, fridge, wifi and charge your phones and you will never need to worry about the 1C or 0.5C of Lithium batteries. Till this date I have never had to draw 100A from my battery bank, with all the load of my house running on my 10Kw Growatt system. My advice, Get Pylontech US3000C and Growatt SF3000TL-48 because they are budget friendly and they work.

[Basil Katakuzinos]

My current system is a Multiplus 5Kva and 3xUS3000C batteries (with 5.4KW of solar also). I am verry happy with it but was asked by a friend what they could expect to pay for a simple inverter to keep on with daily chores and work. 

He lives alone, 2 bedroom townhouse and i thought the above mentioned system would be a great way to keep the lights(all LED), computer and TV on during load shedding (And allot better than those inverter trolleys that cost 10K already and boil those cheap lead acid batteries untill they eventually explode... i had one afew years back... was not pretty).

I also thought a 3kva system would just manage a kettle or microwave, maybe not though.  

So what i have learnt from this thread... 24V = no-no, stick to 5kva or above and avoid the cheaper axperts. 

 

[ianm]

1 hour ago, hoohloc said:

 The 4.6Kw kodac inverter is around R19k. 

[hoohloc]

40 minutes ago, ianm said:

Ok, we are looking at different KODAKs, but Growatt is still cheaper at R6k 

 

Edited October 10, 2021 by hoohloc

[hoohloc]

1 hour ago, Basil Katakuzinos said:

My current system is a Multiplus 5Kva and 3xUS3000C batteries (with 5.4KW of solar also). I am verry happy with it but was asked by a friend what they could expect to pay for a simple inverter to keep on with daily chores and work. 

He lives alone, 2 bedroom townhouse and i thought the above mentioned system would be a great way to keep the lights(all LED), computer and TV on during load shedding (And allot better than those inverter trolleys that cost 10K already and boil those cheap lead acid batteries untill they eventually explode... i had one afew years back... was not pretty).

I also thought a 3kva system would just manage a kettle or microwave, maybe not though.  

So what i have learnt from this thread... 24V = no-no, stick to 5kva or above and avoid the cheaper axperts. 

 

For R30k, your friend can get a decent system if he DIY the installation himself and just get an electrician to split his DB and for CoC 

[JoeyhZA]

1 hour ago, Basil Katakuzinos said:

My current system is a Multiplus 5Kva and 3xUS3000C batteries (with 5.4KW of solar also). I am verry happy with it but was asked by a friend what they could expect to pay for a simple inverter to keep on with daily chores and work. 

He lives alone, 2 bedroom townhouse and i thought the above mentioned system would be a great way to keep the lights(all LED), computer and TV on during load shedding (And allot better than those inverter trolleys that cost 10K already and boil those cheap lead acid batteries untill they eventually explode... i had one afew years back... was not pretty).

I also thought a 3kva system would just manage a kettle or microwave, maybe not though.  

So what i have learnt from this thread... 24V = no-no, stick to 5kva or above and avoid the cheaper axperts. 

 

Sounds like a 24v system violated you and gave you PTSD

There's definitely a place for a 24v config and use cases where they work flawlessly. I don't think it's all as bad as you make out, the Axperts I mean. Those modified sine wave mecer trolley abominations are a seperate conversation though. 

Recommending your config, a multiplus with a bunch of US3000's and 5kw array just to keep lights, a TV and a computer on during loadshedding is an overkill in my opinion. 

Agree with @hoohloc- for 30k you can set something up that will get you through loadshedding just fine and also help bring down electricity costs. 

 

[BritishRacingGreen]

16 hours ago, ianm said:

For a bit more you could maybe consider an installation like this:

5 kW VMIII +  Hubble AM-2

 

It is a nicely matched system as the AM-2 is 5.5 kWh (1C), so the inverter is able to supply the full 5kW (more than enough to boil the kettle).

While I admit that I have no good basis of comparison  , the VMIII just got to be the best bang for buck for me at the moment, I have mksIii , in the same family , and it's just beyond robustness .  I have thrown everything but the kitchen sink at it , and it just makes me sleep well.