Denns

That is wrong. You are describing a transducer, not a current transformer. A current transformer just takes current from one level and "proportionally" steps it to a value that will be used by a device. But it stays a current, so for example 400A to 1 A CT would convert the 400A nominal to a 1A reading. The reading is mostly linear so 200A would be read as 0.5A by the receiving device etc. You choose a knee point high enough so that the transformer doesn't saturate within the required measuring range. The CT has directionality. So, you can determine if current is flowing into or out of a system. Which indirectly determines power flow. There is zero need to talk about Magnetic fields etc to him. He said he is not an electrician/engineer. So just keep the description as simple as possible rather than confusing the gentleman with things that are not relevant. Edit. I am coming purely from an electrical engineering point of view, not in relation to the OPs question in relation to the inverter. So just correcting on the CT part you described.

Last I checked, only industrial users get charged for reactive power consumption. Also how are you measuring or determining the power factor of the bulbs? You have an oscilloscope? And what does your meter say? Does your meter tell you in which quadrant you are operating? I highly doubt a LED bulb does anything to the overall reactive power consumed by the house. If it has any effect, it would be very insignificant and would be a case of a customer asking for 10 cents change on a 1000 rand purchase.

They can't enforce anything, and that is quite evident. No one should waste their time registering. They can't even get people in the townships to move to smart meters.

While I somewhat agree with this. I do think some of the factors are a bit overdone. For other references I used, they mostly sized their battery for 1 day's consumption. Past a certain point it just becomes very un-economical. I for example only have 12kWh but the lowest it has ever hit is 7.2kWh having used about 40% of the capacity. Where I oversized was the PV side of things. My typical load on the house is around 10kWh a day (Geyser is on the controller and have no way of measuring that due to the output of the controller not being a typical wave). My PV (for supplying the house), is only 5.17kW. But that translates to an average generation of 21kWh. That is 4 times what I need so if the sun remotely comes out for an hour or so I am fine. The bulk of my consumption is the pool and fish pond pumps. Shedding those 2 during cloudy conditions, my consumption drops to around 4 to 5kWh. This goes in line with the 1 day rule (LA batteries for 50% is 6kWh). I have survived just fine with little to no issues. I would focus on killing unnecessary loads as you say when the need arises, maximising the panels but would leave the batteries enough for 1 day. Just get a small inverter generator that only charges batteries and that's it.

Yeah, I did mine when the LS had stopped, so the chances of a power outage and a water outage were extremely low. My tank is 2050 litres. Also can push it to 10 days, as we have a pool also. But without worrying about consumption, we still had about half left after a 4-day outage, and the water came back. Pump is a 0.37kW. Single-story house, so we never have issues with pressure.

Water is more important than electricity in my opinion. It was the first thing I ever did also. I supply the whole house with a JOJO tank. Pump only runs when a tap or shower opens.

You could say that but it kind of becomes a lifestyle. You don’t notice after a while. Yes I have a sole converted geyser. It’s geyser controller with 4 panels. EVs sure are nice. Once the batteries are dead I will be getting an EV. And a 48V system with a 12kW inverter to handle the charging of the car.

I agree with Frivan and Bobster. You have to monitor and see over time how your system performs. I recently went off-grid and got my meter and cable removed by City Power in JHB. I had run an off-grid installation since March or so last year. I kept making adjustments, such as making the house very efficient. I have a 3.6kW inverter, but fortunately I have not had issues with overloading, etc., even though the Oven and things like Dishwasher etc are on it. I use Tuya to smart manage everything using smart switches, so the chances of overloading are next to none. Gardeners blower and trimmer don't give the inverter any issues and have been running my grinder and drill on it with no problem, also. With all the power dieting the house went through, I never needed the grid throughout the period. The last month in Joburg and this week in particular has been very bad for generation, and I have never had problems. I don't really monitor the system anymore (I can only monitor consumption via Tuya, I never bought the dongle to monitor the batteries or generation). I have a generator connection, but I have not bought a generator yet. I told myself to only buy one if my kitchen goes out for more than a day due to low SOC on the batteries. My kitchen is on the non-essential side of the inverter (Microwave, Dishwasher, washing machine, Oven, Air fryer, Toaster, Kettle). Because I have GEL batteries, when the SOC is lower, a big appliance kicking in will dip the voltage on the batteries, and the inverter will automatically kill the kitchen, but the house will remain with power. It has honestly happened to me 3 times if not mistaken, in about a year. And always in the morning. I also have a built-in 4 plate gas hob, so I don't really care when it happens. But the power comes back in an hour or so when the generation starts after 7 in the morning. It hasn't inconvenienced me, and it hasn't happened in August last year, if not mistaken and I have made some more adjustments to the system (added 2 more panels on the inverter and 1 on the charge controller). It is otherwise very doable to go off-grid. If I managed with a 3.6kW inverter and GEL batteries, then with your system, it should be quite simple. Just not sure how the Eastern Cape is in winter. Winter in JHB is actually pretty good in my opinion, as no rain and clear skies. I had no struggles in winter. My system will be paid back in 2.5 years. I am almost halfway through now. It is getting sped up considerably as there are no more fixed charges (1.4k is not on my bill anymore). The GELs should last about 5 years, as they always have about 80% capacity left in the morning. Not a bad ROI, I must say. I sized my bank according to the DOD vs Cycle charts online and according to the spec sheet. That is where my 5 years come from. But It theoretically will be around 6/7. But I will be happy with anything over 3. I have balancers on all the batteries and have a fan running 24/7, keeping heat away in an outdoor enclosure that is in the shade. My wife appreciates the work I did (self-installed). We had a few fights over my obsession with going off-grid, as she was just seeing the money being spent but not the vision I had. No surprise estimates and are insulated from the yearly price increases. I used to spend 3 to 4k a month on electricity and still got a 16k surprise bill from CP. That is what got me obsessed with going off-grid, and I developed a certain hatred of Citypower and Eskom🤣.

I have a bit of a different take personally. I view things from a ROI point of view. I would get 1 10kW and not care for redundancy. Why? Modern inverters last for years. Why have 2 to plan for an outcome that will happen once in say 5 years? If one is grid connected, use it. That is your silent generator right there. Will it kill a person to use the grid while getting a replacement inverter or the inverter repaired? I dont think so. If one of the 2 inverters dies after 5 years and it cant be repaired, you are stuck with one small inverter and will be forced to buy 2 again. The other will be sold for next to nothing on the used market. I could see it working if the 1 10kW is that much more expensive than 2 5kW inverters which I am skeptical it is. I have no redundancy for the inverter and am not grid connected and have no worries. But I operate from a perspective of not spending time or money on repairs. When the inverter fails, I get another one the same day or the following day and in 30 minutes I can install it. The broken inverter will probably be listed for sale and be of use to someone else willing to repair it and give it life again. But I also dont/wont spend money on inverters that cost over 20k. I will stick to the Axpert clones that retail for cheap. I can get a 6.2kW for around 6k or a 11kw for around 10k. This is from brands that have been around for years now because I dont believe the big name brands last longer than the clones out there. That is my take basically. I have no generator (I hate them) and have 1 inverter only. I spent 3300 on it and it has run flawlessly for a year. When the time comes as mentioned, I can purchase and install it in a matter of hours. For people grid connected, there is no reason in my opinion for the word redundancy to be a point of discussion unless it takes weeks/months for an inverter to get repaired and you have constant power cuts.

Just get an electrician to remove the equipment and install it at the new place. Nothing can go wrong. Just isolate the breakers/isolators and remove them. The panels can stay VOC and wont care.

Except for the guys behind the scenes making money from the current deals between the munis and Eskom. You are viewing COCT as how you would view a company you are running or would run. These guys don't operate like that. In an ideal world, the munis would be doing everything they can to cut their own costs and use the money for bettering services, but this is SA, and things don't work like that.

Or Eskom has monopolised the supply and is forcing COCT and others to buy from them.

Does he have evidence that you wanted a cheap method for supporting the panel, and did he raise the problems associated with that?

Adding a second geyser driven by a contactor controlled by the thermostat can work very well. just a note on those water saving shower heads. I tried that and it still backfires. The wife just opens the tap to the maximum position and complained it takes too long to wash off her hair. The main fix is more storage. Either increase the thermostat to the highest setting for more energy storage. Or more hot water storage as you say. Or more battery storage to heat more at night.

Never had solar tubes but I would imagine the current wave of geyser controllers making use of solar panels is better than the tube solar geysers. There is zero maintenance and they make use of your existing thermostat so no chance of overheating anything. Panels last basically 3 decades and the controllers are fanless and simple so no moving parts means less likely for something to break. A new controller is anywhere from 3 to 6k depending on what you want. I have had my controller since August last year and have the AC input to it coming from my inverter as backup. It has worked very well and it has run as a standalone system since then. So far, rain/clouds etc haven't affected it much, even though I must say it will obviously depend on how much hot water you go through. In terms of long-term running costs, I think this is by far the cheapest option out there for heating a geyser.

A person with a solar geyser has no business heating up to 60 degrees in my opinion. My geyser is set to 70 degrees. To heat from 40 to 70 is 6.98kwh. Now think about it, that is about 2.3kWh of energy he is wasting by not increasing the thermostat to 70. That is one shower basically. That is why I was wondering why the 4.65 looks low. With your own math, his battery would be over 40% by morning just doing that one simple and FREE thing of just increasing the thermostat to 70. Also, keep the exisitng element. It costs 1.6k to get an element swapped factoring labor. You say his inverter will take a hit. I beg to differ, Just heat the geyer for 1 hour at 5am or even 4am to 5am. Why this time? Noone is awake. Nothing will be pulling more power than what the inverter is using except maybe a fridge and a few lights. The inverter wont break. The batteries are lithium. Why are we even talking about extending the battery life if one has lithium? Draining to 80% or even 90% has been shown that you still get over 3000 cycles. Which is still close to a decade. And keep in mind after 3000 cycles the battery still has 80% of its original capacity left. All of this is FREE. No cost involved and he will be 70% of the way there in my opinion. This is just my take. I have a solar geyser and its set to 70 degrees. The sun is free, why limit yourself to 60? Why not capture the extra 2.3kWh? And for those that say it will scald you. My wife and I have bathed fine for months without issues. I have had a 9 year old shower just fine with no help from adults with 70 degree water. Mixing it is a simple exercise that a 9 year old can do then surely 2 adults can do it. He will achieve little dropping the element to 2kW as he still has to run it much earlier in the night to be ready for showers around 6 to 8am. I have had this issue before. I have GEL batteries and I could not heat in the morning even with a 2kW element because I did not want to drain them to 50% DOD. So I did the next best thing, just increased the thermostat to 70. My batteries are drained to 80/85% by the morning with typical evening loads and dont have to heat the geyser with them in the morning as the water is still plenty hot. And despite having the option to assist with heating using the inverter, I haven't needed to use it. I just over paneled the Geysertech controller with 4 panels rather than the 2HV panels everyone puts.

I suspect they are fully charged. He says his batteries are charged by 11am in summer. So winter I would guess around 1/2 they are charged.

I had the OPs problem also. Tried imposing limits on showering or baths (they love baths) and hot water was always an issue. So just had the geyser converted to solar using a controller connected to 4 panels with my inverter connected via a timer to the controller to assist heating if need be. No limits on her anymore and she fills the tub as much as she wants in the evening and showers every morning. I am yet to use the inverter to assist and have a 150 litre geyser. But on that note, if they are only 2 people. I wonder how a 200 litre geyser isn’t enough. My 150 litre has been plenty for my wife and I. And had 5 people sleep over for a month and didn’t have any issues. Maybe the wife is going overboard with the geyser excessively.

I somewhat agree but I still don’t see why he can’t spend 300 rand a month from the grid for the extra 100kwh for extra heating during winter since he is basically completely running the geyser off solar the other months. it would theoretically take him 25 years to get his money back on a HP, maybe under 20 years factoring the increases. I only recommended the gas heater as he may use less than half a 48kg bottle in a year. Could even be less if used with a Dewhot valve set at 41 degrees. So about 1000 rand a year tops which does come to the cost of running off the grid during those 3 months.

For the OPs case even if a heatpump works or not it is technically still irrelevant as he will never get his money back on the investment. 25k for heat pump, 15k for gas geyser, 20k or so for solar upgrades. To save a few hundred rand a month in electric use for 3 months? It is not practical and he should just leave the system as is unless going offgrid which he isnt. I think we mostly forget why we have solar. Its backup power and saving money. Worrying about using an extra 100 units over winter defeats the purpose of the later. Unless the grid is so bad that you wind up bathing with cold water. These days, load shedding isnt an issue anymore.

That doesnt help him, element size is irrelevant. If he needs 8kWh to heat the geyser then it will take 2 hours vs 4 hours with a 2kW. The energy requirement is the same. More panels also wont help. The issue is not enough storage from the battery to heat. People shower mostly before 7 in the mornng or 8. Depends on work hours, in winter, you generate next to nothing at those hours. generation is also poor after 4pm. His problem is storage. Both hot water storage and battery storage. Which will amount to the same as just installing a gas geyser which will guarantee all the hot water he needs in winter with minimal gas usage.

Gas geyser? From your description it will only get used in winter, so about 3 months which is how long a 48kg bottle lasts when gas heating is used alone. In your case you wont even hit half the bottle after winter is done. That or just keep using Eskom. Any reason you dont want to use Eskom? I am completely off-grid with Citipower having removed their meter and cut the cable so for someone like me I can justify spending to cater for such situations, but in your case, unless you want to be off-grid, dont waste your money catering for 3 months of the year. Just spend the extra on eskom and call it a day. It will take you a decade to recover your money on any solution that will cover winter. Heat pump is a no as Scorp has said for winter. Adding a second geyser is a no also as it sounds like you cant even get the one geyser to full temp in winter, how will you do 2? My recommendation is leave as is and spend the few hundred rand from eskom. Edit: Does seem newer HPs still work fine in sub zero temps. Older models struggle.

Someone I know did 8 panels with the cabling etc and paid 30k. But you can probably do it cheaper. But remember, cheap isn’t always best, especially when it comes to installing on tiles. Lots of installers out there don’t do it right.

Wouldnt you just be removing the positive and negative and connecting the new battery with comms cable? Or did you change the DC Isolator/Breaker also? I dont see where the complication is if you had an exisitng install. Is it a replace battery situation or added a new battery?

Can just add a simple buck/boost converter in between without having to modify the board. The converters are super cheap also. And he just scales accordingly.