For me:
~81% comes from Solar
~156kWh / R376 from grid, prepaid per month
~656kWh / R1,762 from sun, saving per month
~812kWh / R2,264 total if no Solar+Battery per month

Note: Rand amounts are based on prepaid CoJ for corresponding kWh
Will save more Rands when CoJ implements increases in July 2024.

49 minutes ago, zsde said:

depends on the Municipal area. Ekurhuleni has that policy

 

I was told, by a contractor, that COJ have this policy too. But I hear lots of stories about people who are going undisturbed by the City, and I hear lots of stories about people getting the feed to their house cut or their meter removed without any negotiation or warning. So IDK. I buy a tiny amount every 2 or 3 months just to ward off the bogey man of disconnection.

2 hours ago, Bobster. said:

every 2 or 3 months

precisely what I do. and when there are bad solar days I just switch over and use some of those accumulated credits

9 minutes ago, zsde said:

precisely what I do. and when there are bad solar days I just switch over and use some of those accumulated credits

I just leave my grid feed on all the time. But sometimes I wish I could put a timer on it. I'm averaging 2.4 units a day, over 4.5 years, so it's hardly breaking the bank. But some of that power that gets used every day is the inverter switching back to grid when the loads get very low - which it won't do if there's no grid. So I could stretch things a bit further if I could switch the grid off at night and not have to worry about remembering to turn it back on.

Shouldn't be hard really. A relay that handles > 50A, and a timer to control that. Or a 50A timer if there is such a thing.

But maybe it's a complication too many. And it would take another 5% or so out of the battery if my thumbsuck calculations are correct.

On 2024/05/10 at 12:14 PM, LiFePOWER said:

double gas oven,

Gas ain't exactly getting cheaper... if you're in an area that has more sunshine than cloudy days (not the Cape coastal areas) and you have more space for more solar, I'd suggest go that route, as well as solar HWC, possibly, here in the green Kalahari, even now the 12 evacuated HWC without any other heating still produces water that will burn you at this stage of the year/season.

Also try and do some measurements/graphs on what all your power is being used up by. My mom with my better half, down against the Tygerberg Hill in Bellville at the moment, use on average 10kWh/day, no solar, unfortunately, but HWC only gets turned on, when a shower or bath is on the schedule etc. I can't believe the low consumption, but HA with a PZEM-004T connected to a ESP-01S and reporting via WiFi every 5 seconds or so, is indicating that they are using less than half of my usage and I have no HWC that is heated with electricity here... but then again, no grid connection here either...

Usage for today...

and usage for this month so far...

37 minutes ago, Bobster. said:

Shouldn't be hard really. A relay that handles > 50A, and a timer to control that. Or a 50A timer if there is such a thing.

If you are running HA, you could add in a ESPHome based relay that drives a contactor, that disconnects you from the grid, when battery above a certain %age and sun is below horizon and re-connects you when battery goes below a certain %age or when sun is above the horizon again...

3 hours ago, Bobster. said:

I was told, by a contractor, that COJ have this policy too. But I hear lots of stories about people who are going undisturbed by the City, and I hear lots of stories about people getting the feed to their house cut or their meter removed without any negotiation or warning. So IDK. I buy a tiny amount every 2 or 3 months just to ward off the bogey man of disconnection.

That's crazy. Surely they can't just disconnect you. 

19 minutes ago, Kalahari Meerkat said:

Gas ain't exactly getting cheaper... if you're in an area that has more sunshine than cloudy days (not the Cape coastal areas) and you have more space for more solar, I'd suggest go that route, as well as solar HWC, possibly, here in the green Kalahari, even now the 12 evacuated HWC without any other heating still produces water that will burn you at this stage of the year/season.

Also try and do some measurements/graphs on what all your power is being used up by. My mom with my better half, down against the Tygerberg Hill in Bellville at the moment, use on average 10kWh/day, no solar, unfortunately, but HWC only gets turned on, when a shower or bath is on the schedule etc. I can't believe the low consumption, but HA with a PZEM-004T connected to a ESP-01S and reporting via WiFi every 5 seconds or so, is indicating that they are using less than half of my usage and I have no HWC that is heated with electricity here... but then again, no grid connection here either...

Usage for today...

and usage for this month so far...

I know someone who thought they would save money going gas hot water. Gas costs him R1000 a month. 

Gas geyser same price as evacuated tube solar geyser that I have had for 12 years. Only have to use electricity in winter and really cloudy days to heat it a little or I just leave the element breaker off. 

The new solar geysers are so efficient. Mine is outside on the roof and in winter it's still warm enough to shower the next morning. 

1 hour ago, Bobster. said:

 So I could stretch things a bit further if I could switch the grid off at night and not have to worry about remembering to turn it back on. 

Shouldn't be hard really. A relay that handles > 50A, and a timer to control that. Or a 50A timer if there is such a thing.

But maybe it's a complication too many. And it would take another 5% or so out of the battery if my thumbsuck calculations are correct.

From my memory I would not have thought you actually need 11.5 kW peak power for the low energy used? 

If not needed you can use a WiFi smart switch that you can easily override from remote. At our age we need to get gadgets that can help where we might forget. Further could it not work to only switch the grid to the inverter off instead of the whole DB? 

If afraid of battery being discharged to low the smart switch could perhaps switch the grid to inverter on say around 05h00 or a suitable time based on discharge level. 

@Chris_SChris_S if one uses a constant amount of hot water then I feel gas can turn out expensive. If only a few times during the day then the keeping a element geyser on temp without PV can be costly.

Following the laws of physics gas does convert less heat than direct electricity. This will always be an ongoing debate. 

Apartments with 2 people can indeed be cheaper on gas. 

Edited May 17, 20242 yr by Scorp007

3 hours ago, Scorp007 said:

From my memory I would not have thought you actually need 11.5 kW peak power for the low energy used?

Your memory doesn't fail you. But the municipal breaker is 50A and so I'm thinking I have to have something with a similar rating. 

Though a lower rating endangers the breaker if anything, not the cable. 

4 hours ago, Chris_S said:

That's crazy. Surely they can't just disconnect you.

I'm told not. I just hear lots of versions of this story. It is possible that in some cases some details are omitted. 

So I don't KNOW. So I feed the thing a small amount every 2 or 3 months to be safe. 

Does anyone use Solarman App to check how much money you have saved?

I have a 5Kw Deye inverter  with 4Kw solar panels and 2 Volta batteries connected with the Solarman App

We've been going now for about a year, so I can add some stats. In the beginning it took us about a month to play around a bit with the system and what pulls and when it pulls. We've also had all four seasons go by too. 

2023 - Gone from pulling 88.6kWh a month from the grid to
2024 - Currently pulling 18.1kWh a month from the grid

We have some weeks where we will pull 0kWh from the grid and will produce between 25/30kWh a day from solar.  We're on prepaid my wife just loads R50 on each month, just to keep the man happy and to keep some credits just in case. 

When the sun is like it is today, I load it, dishwasher, both geysers (3000w + 3500w), 1000w pool pump, fridge/ freezer, anything that I can throw at it and the sunsync 8kw inverter just takes it. I'm yet to find the peak of what I can use. I've even had the welder and lawnmower on with all of the above and no problem.  

My system reckons I've saved about R21 000 in this period. 
 

How do you see how much you have saved ? I have put in the r/unit value but cannot find where it gives me the monetary value.

1 hour ago, Deonal said:

How do you see how much you have saved ? I have put in the r/unit value but cannot find where it gives me the monetary value.

It gets put into the 'Investment return rate' section at the bottom of the Overview tab of the mobile-phone app. It doesn't seem to appear on the web portal, however.

On 2024/05/09 at 10:59 AM, Hyarion said:

We use around 300-350kWh from Grid/Eskom per month now. 

Solar + Battery accounts for approx. 65% of our usage.  More batteries would increase that percentage but we don't really have the space for more.

Almost identical to mine.

300-350kwh per month grid.

Total use 1.05mwh

3x hubble Am-2

12x 450w panels

On 2024/06/06 at 4:58 PM, JayMardern said:

It gets put into the 'Investment return rate' section at the bottom of the Overview tab of the mobile-phone app. It doesn't seem to appear on the web portal, however.

Thanks a ton

 

My totals per month.

16 x 550 Panels

3x 5.12 Batteries

7.2kw Inverter

Edited June 16, 20241 yr by Raiden2912

On 2024/05/18 at 8:29 AM, Deonal said:

Does anyone use Solarman App to check how much money you have saved?

I have a 5Kw Deye inverter  with 4Kw solar panels and 2 Volta batteries connected with the Solarman App

This SOLARMAN App, I’m a battling to get it working with my WiFi enabled Inverter….will let you know when I get it working.