So Tshwane has started forced installation of prepaid meters, my house done today. Their argument is that it is required to be able to sell power back to Tshwane. When prodding them about me being able to sell excess power it appears that they cant do this "yet". Thus its unlikely to happen given their track record. I generally am a calm person but this is a "last straw" scenario with a situation where things are forced on the consumer with little to no truth in the reasoning provided behind the process. Anyways I digress...

This last straw has cause me to start evaluating my options and planning my journey to completely "off grid".

 

NOTES. I have an existing solar system. And off grid can only be for power and not for water as we are not allowed bore holes due to dolomite rich soil.

 

Current Solar PV:

• 2 Victron Multiplus 3kva's in parallel
• 3 Pylon US3000's
• Victron 150/100 MPPT
• Venus
• 12 Canadian solar 330W panels facing around 350degrees (angle of the house)

Current Water heating:

• 150l retrofit standard geyser conversion evacuated tube solar geyser
• Geyserwise to run it.
• Geyserwise on dedicated solar line with the Geyserwise driving a contactor for the geyser power input from eskom.

 

Some notes:

• I cycle my batteries every night they drain down to 40-30%. Min set to 20%. 
• I have a full gas stove. House is running exclusively on the PV solar with the geyser and three kitchen plugs on Eskom.
  • Fridge
  • Freezer
  • Chest Freezer
  • Tv/Hifi/Wifi
  • Big old school (speedqueen type) washing machine
  • Lights
  • Ironing (in the day)
  • Vacuuming
  • Hairdryer (this one taxes the  batteries in the morning but you have to keep the wife happy
• The kitchen plugs run on eskom: Kettle, MW, Toaster, Air-fryer, Tumble Dyer, Dishwasher. Tumble dryer only used when its raining and dishwasher hasnt been used for a very long time.
• Currently I consume around 13-15KWh PV per day. My PV reliably generate around 18-19KWh on my 12panel/150-100MPPT.

 

My thoughts are as follow:

• That my battery bank is too small. I need another US3000 or need to get rid of them and get a freedom1 of around 15KW. Issue is that on days where the day starts overcast that I cant generate enough PV to get some juice back and carry the house. (battery R18K)
• My panel bank is too small. I dont have more space on the north side and am contemplating putting perhaps 6x 650w panels on the garage roof (Panels R25k). Would need to elevate them slightly. This will effectively double my PV potential. If Tshwane decide to buy my electricity then I can sell around 20KWh back to them every day by adding another MPPT. (MPPT 12K)
• I am moving two more plugs onto PV.
  • I am putting the MW on PV. One seldom use the MV for more than 2mins to warm food maybe. 1kw for a few minutes is nada.
  • I am putting the Air-Fryer on PV. 2KW for around 15mins is around 500Wh. This is a lot yes but I will need to manage it. Can perhaps plug it into eskom
  • Kettle going on stove. Done
  • Leaving Toaster, Dryer and Dishwasher on Eskom and will reduce usage to as little as possible.
• I will install a gas geyser in line with solar geyser and effectively use the Geyserwise to switch off any Eskom involvement unless urgently required. Problem I have is that my bathrooms are on opposite sides of the house. Plumbing 15m apart. Efficiency would be much better if I could install two. One on either side. Can one run a gas geyser in a roof void? (14k)
• I may add another 150l geyser to the mix to store solar heated water more efficiently.  Effectively have two reservoirs I can use with a solenoid valve in place to use warm one. (R4k)
• labour for my account and probably plumbing and cables adding anothre (R10k)

 

What are your guys thoughts? What would the right gas geyser be to go for? I am considering Paloma (I dont know what the max temperature water is that you can supply it with tought) or a Bosch Optiflow with Bluetooth (One that can handle being fed 60 degree water form the solar heated geyser - bosch specs says max 80degrees) What else a I missing? Yes above is not completely off grid but the first step. a 20kwh battery in the system with a generator as backup would probably put me there...

 

 

 

Edited September 19, 20223 yr by JTK

Tshwane installed the prepaid meter so there is no chance of you rolling the meter backwards. Nothing lost there. You were not allowed to do it anyway.

Your best bang for buck will always be more solar panels, you can always find more creative uses to use/store the energy.

I run my whole house (incl stove & induction cooker & heatpump on PV/battery). My battery gets me through most days without needing to buy units.

In terms of ROI batteries are just a poor investment(at current prices), due to Eskom we do not have any other choice. Getting enough batteries to get through loadshedding is in my opinion a good investment as this allows me to continue working, any excess is throwing more money towards a losing investment. 

 

 

@iiznh: Tshwane in their communication said they are rolling out the smart prepaid meters to enable us to sell power back to Tshwane...  Now it seems they will not allow this as no one at Tshwane knows anything about it..  That is really what irked me... Yeah I know I could not sell back. But they used this ruse as specific reason for forcing everyone to convert... Now I have to pay a middle man for electricity... This whiles Tshwane will likely not reduce their staff that handled the billing before the forced conversion, making the cost per unit more.

 

Again I digress. Just so fed up with lack of proper service.

47 minutes ago, JTK said:

@iiznh: Tshwane in their communication said they are rolling out the smart prepaid meters to enable us to sell power back to Tshwane...  Now it seems they will not allow this as no one at Tshwane knows anything about it..  That is really what irked me... Yeah I know I could not sell back. But they used this ruse as specific reason for forcing everyone to convert... Now I have to pay a middle man for electricity... This whiles Tshwane will likely not reduce their staff that handled the billing before the forced conversion, making the cost per unit more.

 

Again I digress. Just so fed up with lack of proper service.

Do you belief their reasons given. They dispute it is thjse that don't pay their post paid accounts. I tend to think it is.

Why are they only doing 1 meter per 4 months at rondom in the suburb and not more at once.

Another person told me he feels its because he put in solar and the account is very low.

@iiznh

I have to agree with you. Step 1 is to cut the wasting of power by the OP at the rate of power being used.

I use the same gadgets as you for making food and heating water. With long LS I heated my water with 1.62kw of panels in full sun without any battery power. Some below 100W loads were on in the house. Yes I did switch my fridge combo and freezer off. With good sun and cold days in Aug I used less than 1kwh from the grid a day. Only 2 of us but when the grand kids come visit and bath I do use a lot more power even with the heat pump. Also more food to prepare.

My management of loads is still old style via 6 Sonoffs.

17 minutes ago, Scorp007 said:

Do you belief their reasons given. They dispute it is thjse that don't pay their post paid accounts. I tend to think it is.

Why are they only doing 1 meter per 4 months at rondom in the suburb and not more at once.

Another person told me he feels its because he put in solar and the account is very low.

@iiznh

I have to agree with you. Step 1 is to cut the wasting of power by the OP at the rate of power being used.

I use the same gadgets as you for making food and heating water. With long LS I heated my water with 1.62kw of panels in full sun without any battery power. Some below 100W loads were on in the house. Yes I did switch my fridge combo and freezer off. With good sun and cold days in Aug I used less than 1kwh from the grid a day. Only 2 of us but when the grand kids come visit and bath I do use a lot more power even with the heat pump. Also more food to prepare.

My management of loads is still old style via 6 Sonoffs.

They actually came and replaced all the meters in our estate (friday and today)... So I am not isolated. And yes my electricity bill is paid every month . Yes it is relatively low due to my creative way of managing my loads. 

But we are digressing. The discussion isnt around Tshwane. Tshwane was just the cause of me deciding to try and go off grid completely...

So please ignore the Tshwane part.. Could we center around my thinking and your inputs on that perhaps please?

14 minutes ago, JTK said:

But we are digressing. The discussion isnt around Tshwane. Tshwane was just the cause of me deciding to try and go off grid completely...

So please ignore the Tshwane part.. Could we center around my thinking and your inputs on that perhaps please?

My input is as per @iiznh

Prefer to use PV for the loads instead of gas or solar geysers for heating. Also mentioned that you could try and limit actual use. I also used to use 40kwh a day and still in the same house. Without knowing your load profile and at what time I cannot even try and suggest how and what. That is the 1st thing must know to have a picture. Without it it is like i want to buy a car. What do you guys suggest?

Some installers would put their load measuring stuff in a apartment for 3 weeks before they even try to quote on a PV system.

 

Edited September 19, 20223 yr by Scorp007

36 minutes ago, Scorp007 said:

My input is as per @iiznh

Prefer to use PV for the loads instead of gas or solar geysers for heating. Also mentioned that you could try and limit actual use. I also used to use 40kwh a day and still in the same house. Without knowing your load profile and at what time I cannot even try and suggest how and what. That is the 1st thing must know to have a picture. Without it it is like i want to buy a car. What do you guys suggest?

Some installers would put their load measuring stuff in a apartment for 3 weeks before they even try to quote on a PV system.

 

I have a fairly good idea of my load profile. Perhaps it did not come across that way. I use around 14KWh excluding Geyser per day. There are 5 people in the house. 4 of whom does a morning and evening bath/shower... To cater for the evening bath another evac tube attached to another 150l geyser is likely to help.. But the morning bath is the problem, hence the gas proposal...  As to the balance of the load. Happy that I can cater for it by perhaps just adding one battery to my bank... Would love to be able to sell back because then I can perhaps find a way to cater for Eskom warming the morning bath geyser by adding another bank of panels exclusively to push back into the grid to use the credit tomorrow morning. Geyser is on a timer using the Geyserwise and is turned on selectively only for 90mins before the first bath to get the temperature up to standard...

Edited September 19, 20223 yr by JTK

16 minutes ago, JTK said:

Would love to be able to sell back

That should be your lowest priority. Yes, it would be nice to get something back. Budget to cover your needs first. If you believe that they will ever deliver on promises, then the LS should serve as another reminder of promises that have been made for how long already? You seem to be optimistic to get a return on an investment made for the sole purpose of selling back. Forget that until there is some firm legislation in place.

 

1 hour ago, Scorp007 said:

Another person told me he feels its because he put in solar and the account is very low.

That is not a maybe. Strange how I was targeted for prepaid recently without asking for it. And yes my electricity consumption dropped to less than 10kWh/month grid since last December. And no, there has never been a general roll out of prepaid in our area, it was always by request and a pre-notification. In my case none of that occured.
Then my neighbour put in his Solar 3 months ago. No surprises, he was just targeted for prepaid too. 
They actually believe that we must be stealing power from others.

17 minutes ago, zsde said:

That should be your lowest priority. Yes, it would be nice to get something back. Budget to cover your needs first. If you believe that they will ever deliver on promises, then the LS should serve as another reminder of promises that have been made for how long already? You seem to be optimistic to get a return on an investment made for the sole purpose of selling back. Forget that until there is some firm legislation in place.

 

That is not a maybe. Strange how I was targeted for prepaid recently without asking for it. And yes my electricity consumption dropped to less than 10kWh/month grid since last December. And no, there has never been a general roll out of prepaid in our area, it was always by request and a pre-notification. In my case none of that occured.
Then my neighbour put in his Solar 3 months ago. No surprises, he was just targeted for prepaid too. 
They actually believe that we must be stealing power from others.

There is no doubt that utilities do look for people who are dropping off the radar, and then investigate to see what's going on. This is not unreasonable, and Tshwane recently inspected some quite up market properties on a very nice estate and found meters by-passed and other goings on. 

I've had City Power paying me a lot more attention since I made the change to PV. They've come around, been very polite, taken photos of the meter, and it's clear that what has happened is that they see I haven't been buying pre-paid power from them, when I used to buy regularly, and so they wonder what has changed. I don't mind.

I don't know if COJ are forcing people onto pre-paid. They can't play that card with me because I already was on pre-paid before I switched to PV. 

I made that change (to pre-paid) because it saved me money. So check the tariffs to see if you might be saving on the small amount of power you still consume. In my case I am saving about R700 per month on flat fees that aren't applied to pre-paid accounts.

18 minutes ago, Bobster. said:

So check the tariffs to see if you might be saving

That's the first thing I did. In fact, it was the quickest service I have ever received from the Municipality.
Never even knew we had a Tariff A and B in Ekurhuleni. I had been defaulted to B ever since, which means a flat rate per kWh no matter the usage.
Filled in the form and Tariff A was activated immediately.
Now I have to charge the prepaid at least once in 3 months apparantly, else it disconnects. 
https://ltcelectricalservices.co.za/electrician-in-edenvale-and-bedfordview-boksburg-benoni-germiston-bruma-alberton/ekhureleni-electricity-charges-explained/

22 minutes ago, Bobster. said:

saving about R700 per month

since the Eksdom link was severed here, the monthly before electron consumption saving is probably not far from R 2k a month, the actual electrons used to add between 600 and 1000 extra ZAR's on top of the fixed fee... I asked for a pre-paid option, but they said it wasn't available to us... I guess that could be called discrimination...

Either way, for @JTK, I would strongly suggest  to stick to 48V inverters and batteries, not to go with a 24V system, which I suspect the 3kW unit may be....

5 hours ago, JTK said:

I have a fairly good idea of my load profile. Perhaps it did not come across that way. I use around 14KWh excluding Geyser per day. There are 5 people in the house. 4 of whom does a morning and evening bath/shower... To cater for the evening bath another evac tube attached to another 150l geyser is likely to help.. But the morning bath is the problem, hence the gas proposal...  As to the balance of the load. Happy that I can cater for it by perhaps just adding one battery to my bank... Would love to be able to sell back because then I can perhaps find a way to cater for Eskom warming the morning bath geyser by adding another bank of panels exclusively to push back into the grid to use the credit tomorrow morning. Geyser is on a timer using the Geyserwise and is turned on selectively only for 90mins before the first bath to get the temperature up to standard...

I still maintain your best path would be to get more PV. Dump excess power into the geyser that needs to run the bath by installing an element suitable to your inverters. Insulate the geyser well. The geyserwise only allows 65degrees and this is not optimal, I would personally up that to 75-80 degrees and rather install a thermostatic mixing valve to mitigate the risk of burning. Gas is a great backup, though you have no control over the price & availability. We can easily get into a situation where there is a gas shortage too, just look at europe. I hope I am wrong about this.

 

My heatpump works well to reheat the water for morning showers/baths for about 1 - 1.5Kwh of battery power

Edited September 19, 20223 yr by iiznh

15 hours ago, Kalahari Meerkat said:

since the Eksdom link was severed here, the monthly before electron consumption saving is probably not far from R 2k a month, the actual electrons used to add between 600 and 1000 extra ZAR's on top of the fixed fee... I asked for a pre-paid option, but they said it wasn't available to us... I guess that could be called discrimination...

Either way, for @JTK, I would strongly suggest  to stick to 48V inverters and batteries, not to go with a 24V system, which I suspect the 3kW unit may be....

nope. 48v MP2's in parallel

On a vaguely related note.. do CoT PV owners have to register their systems? I have seen some draft regulations from 2017, but I am not clear if it is in play at the moment. 

@GTP Did you get an answer on whether PV systems in Tshwane needs to be registered.  I could also only get the old references.

No requirement to register the system.