Interesting price difference between solar with grid backup, and going off-grid

RaptorSA said:
"an Eskom connection can provide peak power of up to 13kW in average households, meaning you can easily run multiple power-hungry appliances such as stoves, kettles, geysers, washing machines, and pumps without the power tripping."

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I have an SunSynk 8k - under normal circumstances it has no problems with 13kW loads in pass through mode.
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Most installation will split the DB into Essential (UPS) loads and Non essential loads.
The Non-essential loads are on the grid side of the inverter.
There is a sensor (CT-Coil) by the meter that is used to prevent or allow feeding Eskom.
The inverter will supply power to UPS, then to Non-essential side up to the rated capacity.

EDIT: a geyser timer is a good idea
 
Speedster said:
Or just be willing to suck it up if the 5% happens to overlap with loadshedding?
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Sucking it up and using LED lights for 2h is quite doable as it is unlikely to happen if you set things up.

You can configure the inverter to have small reserve of battery (eg 20% battery) to cover you for the 2 hours of load shedding.
If the battery drops below the threshold during load shedding, you can recharge from the grid when load shedding stops [Not good for Eskom]

In my case the reserve is 20% and is only used if load shedding.
So far all good, even with level 4.
I've not used the grid to charge the battery.
When it rains for a whole day the battery stays at 20% reserve and I used grid.
 
system32 said:
Sucking it up and using LED lights for 2h is quite doable as it is unlikely to happen if you set things up.

You can configure the inverter to have small reserve of battery (eg 20% battery) to cover you for the 2 hours of load shedding.
If the battery drops below the threshold during load shedding, you can recharge from the grid when load shedding stops [Not good for Eskom]

In my case the reserve is 20% and is only used if load shedding.
So far all good, even with level 4.
I've not used the grid to charge the battery.
When it rains for a whole day the battery stays at 20% reserve and I used grid.
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So after sunset (when there is no PV) does your system switch over all loads to Eskom? Or the batteries & inverter continue to supply all loads until the batteries reach 20%, the switch everything over to Eskom?
 
A friend moved completely off grid, installed solar and a backup gen. He saves between 7 and 8K every month on the connection fee alone, in his situation its makes perfect sense.
 
Complex is a bit backwards disallowing solar but at least can do gas and battery systems. Would love some panels, not bad prices in this article.

If you go over the capacity of a 600kwh solar only system is the extra drawn from Eskom or does it trip the earth leakage?
 
Other Pineapple Smurf said:
Valid point.

I would still keep my generator when I go solar one day. Will still be on-grid as the generator would only be used for winter load shedding during the day. I would also have it wired up to feed into the house then.

A generator is still more expensive than Eskom but way cheaper than more panels.
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My generator is linked to my batteries. So when available kWh drops below 30%, the genny kicks in and recharges the batteries. When they reach 75%, the genny shuts down again.
Just found this way to be a better and more efficient way of making use of it. The installation was also simpler and there is no noticeable switch over when it needs to kick in.
So my batteries are charged either by, PV, wind or genny.
 
WollieVerstege said:
My generator is linked to my batteries. So when available kWh drops below 30%, the genny kicks in and recharges the batteries. When they reach 75%, the genny shuts down again.
Just found this way to be a better and more efficient way of making use of it. The installation was also simpler and there is no noticeable switch over when it needs to kick in.
So my batteries are charged either by, PV, wind or genny.
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What system do you have? And generator?

I'm investigating all options regarding the aux input on my sunsynk.

My batteries are at 20% by 4am and having a generator start up at that time of the morning will drive me and my neighbours crazy.

Edit only se nie that you also have a wind turbine.
 
RaptorSA said:
"R242,000 for 1,200kWh of consumption."

That is a kukload of energy and I have poor family members that'll spend more than that on a bakkie.
So maybe it's just me, but that's cheap.

If that's a good quality 20 year system it's R1008K PM.... to be completely off grid. No more loadshedding, home value increase etc.

It's a no brainer.
What am I missing here?
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It’s R836,000 to be completely off the grid.
 
I don’t really see much point in being completely off the grid.
 
BBSA said:
You never get periods with no generation. Yes, sometimes it is only 10 or 20 percent of normal production, but you still generate some.
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Correct

Here are three months to compare

November - sunny most of the time

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Jan - raining almost non-stop

1651050614949.png

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April - was raining quite a bit BUT very very very dark days still great overall results for the month

1651050661448.png
1651050758023.png

It was not because we have less hours etc in april my biggest solar production day was yesterday

1651050801501.png

If I cut everything down to absolute essentials I could run around 5 days 0 sun, but goal wasnt to be offgrid but to have absolutely minimal reliance on Eskom please note that even though I have usage that can all easily be 0 we dont want to change our lifestyle at all but CAN if we had to.
 
I believe that price difference was an extreme3ly calculation by someone pushing on-grid systems or wanting to optimize with an underrated system..... I have seen that latter in many a case.

take a 5 KW system with a 10 KVA battery backup --- Should cost less than 100K.
Now if you scale that for off-grid: bit more panels and bump the batteries to 40KVA, add a second 5KVA in parallel.... And you are most 230K.... Change you geyser to solar - taking hte best of quality you can by, another 20K. Stives either gas, but you may do also on indusction(wiht this). All you other things being A+++ or A++ and you should be there in general.

So make it 250 for a 10KVA with 40kVA battery backup should be enough or 80% of homes for a fully off-grid. A far cry from the suggestion in this article.
 
Snyper564 said:
Correct

Here are three months to compare

November - sunny most of the time

View attachment 1299038

View attachment 1299044

Jan - raining almost non-stop

View attachment 1299040

View attachment 1299048

April - was raining quite a bit BUT very very very dark days still great overall results for the month

View attachment 1299042
View attachment 1299050

It was not because we have less hours etc in april my biggest solar production day was yesterday

View attachment 1299052

If I cut everything down to absolute essentials I could run around 5 days 0 sun, but goal wasnt to be offgrid but to have absolutely minimal reliance on Eskom please note that even though I have usage that can all easily be 0 we dont want to change our lifestyle at all but CAN if we had to.
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Totally agree with you on that
 
noxibox said:
I don’t really see much point in being completely off the grid.
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I is actually less costly and easier than this article suggest... I have aquite a munmer of cloeinets, and also towers completely off-grid..... this article was skewed to push a specific narrative
 
WollieVerstege said:
My generator is linked to my batteries. So when available kWh drops below 30%, the genny kicks in and recharges the batteries. When they reach 75%, the genny shuts down again.
Just found this way to be a better and more efficient way of making use of it. The installation was also simpler and there is no noticeable switch over when it needs to kick in.
So my batteries are charged either by, PV, wind or genny.
Click to expand...

I never thought of that setup. Way more efficient than just running the generator for a variable load.
 
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