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Bobster.

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Everything posted by Bobster.

  1. OK. I know of two kinds of audit, but they really amount to the same thing. 1) Routine audit 2) Checking your meter because the usage has dropped significantly In both cases they are going to check for tampering, for signs of bridging, and that the serial number on the meter matches what they have on their database for the property. If the meter number is correct and there's no signs of bridging then how you can you be stealing? They might ask if you have an alternative source of power, but I presume that is they because they are tired of getting electric shocks when they think the power is off. I've had them several times at my place since I went to prepaid. Since I got solar they have, on a couple of occasions, taken photos of the panels on the roof, but nothing happened as a result. I'm currently registering my system with the City. There is a process. It is supported by (poorly communicated) by-laws. I figure that at some point they are going to get more aggressive with this requirement. Part of that process is a warning sign on the box where the municipal breaker and the meter live, warning that there are dual sources of power on the property.
  2. Eish. I just spotted that @psyclown was not actually asking those questions of me.
  3. I have a surge protector on each string of panels. I also a pair of Dehnguard SPDs on either side of the inverter. So the order is Grid -> SPD -> Input to inverter Output from inverter -> SPD -> backed up circuits. The garage door is on the backed up circuits. I detailed this in another post. Sorry for not responding to you first. They will pay for a REPAIR if I provide photographic evidence (of what?), a quote, a report from whoever is doing the repair, and I have to supply that in advance. In the event of a replacement there must be a credible report explaining why a repair was not appropriate.
  4. I wanted to claim for my garage door motor from insurance. I suppose I might do the same if I were them, but they are laying down a lot more rules. I would have to submit the claim BEFORE replacement, and it would have to be a quote for repair. There would have to be a report from the installer or repair person to justify the repair. If I claim for an entire new motor then there has to be a more detailed report explaining why replacement is the only option. They also want photos of the damage. Like I can crack the thing open and show a burned out track on a PC board and how the numbers on the display aren't right (which I didn't notice. The installer spotted it when he went to collect the motor after the first repair). I'm toast in this case. Faced with repeated explanations of how the suppliers (not my installer) are out of stock of some piece or another, I bit the bullet and paid about R1600 extra for a whole new install, including the shaft that takes the drive from the motor to the door. Insurance will now say that I elected to have a replacement (which is true) when a repair would have sufficed (probably, if the parts ever arrive). Difficult. Apparently Digidoor are under huge pressure at the moment with a large number of motors damaged by lightning. I can argue for the insurer here. They would have paid for the repair, but I went ahead and got a whole new motor (on the basis that it will be good for years to come as long as there is no more lightning damage).
  5. Ummmm.... Think of my worst case scenario. Early morning outage, bad weather. Now when your pool pump kicks in it's going to be taking the best part of a kW and that will all come out of your battery. 3 hours of pool pump can be 20% of the battery. If that smart switch will disconnect the pool pump when the grid is down then that sounds OK. But think about this. In the example I gave earlier the pool pump would have seriously increased the load on my battery. OK... I could always get off my lazy butt and throw the circuit breaker on the DB, but that would have to occur to me whilst I'm making coffee and talking to people at the office.
  6. You are right to think about the extra battery. My rule for explaining this is that panels save you money by grabbing free electricity, batteries protect you against outages. So more battery gives you more protection. Those fridges are not going to draw a lot. The oven you will have to control, or get an air fryer which is quicker and cheaper to run. I don't feel I can offer an opinion on the inverter question. Here's the graph for my system so far today Now from midnight to just on 6:00 you see a fairly flat line. This gets close to 300W but never that far. That is the house ticking over at night. Deep freeze (modern), 2 fridges (both inverter drive), external lights, wifi, security system, stuff on standby (EG TVs). That's why I say your fridges shouldn't use much if they are fairly new, efficient models. Now at 6:15 the water heating (heat pump) turns on. At that point I have 63% of the battery left. Rule of thumb for batteries - you get 90% of them. The BMS usually doesn't allow the battery to get all the way flat. I have a 10kWh battery. So at the point the water starts heating I have an effective 5.3 kWh available. Because the outbuildings (which includes the pool pump) are not backed up, I won't be using a lot more in the house if we are disciplined so I can go a few hours yet - especially if the sun shines. I recently survived a 10.5 outage starting at 2 am, with not very good weather. But if the battery were 5kWh the picture changes. I'd have used the same amount to get me that far - 3.7 kWh. I'd have had 1.3 kWh left, and effectively 800kWh after knocking off that 10%. I'd have had much more of a fight on my hands. Most days I don't need all of that 10kWh, but we don't always get 2 hour outages as per schedule, so when there's a long outage and the weather is not so good I'm happy to have it. There's just two of us in this house, so we can keep the consumption very low after hours. The more you use, the more that 5kWh battery will get stretched. So another thing all new owners have to go through is figuring out WHEN you use electricity, how much, and how much of that you can move into the daylight (free electricity) hours. So we run the pool pump during the day, the dishwasher during the day, the air fryer during the day where possible. If I turn the 2nd geyser on (it's on a time switch), then I do that during the day as well. Then at night when we are relying on batteries we can stretch them a long way, and that buys us protection in the early morning when the system is at it's lowest charge. We all have to go through this learning curve and figuring out how to optimise things. The pay off is making best use of the free electricity when the sun is shining (EG running the dishy during the day), and best use of the stored power (battery) when the sun goes down.
  7. The helpdesk have confirmed that Goodwe pushed that update through. So despite not selling Goodwe inverters any more, they still have an open channel to them.
  8. I hope @LLTHB has been following this. After Tuesday's test I left the system in economic mode. This morning we had load shedding starting at 6:00. The inverter reports utility loss at 6:01 and at time of writing power is not restored. It's a nice sunny morning. Here's the graph As usual, the PV starts shooting up around 8:15. But as early as 7:45, PV is double load and the battery is charging. Then at 8:15 we see the load increase a little, but PV shoots up a lot. PV is no longer tied to load when the grid is down. This is under the following conditions Grid: no grid Inverter mode: economical Safety code: 230V 50Hz default. Firmware: 2121E At 8:31 I changed the safety code back to the South African code. At 8:33 SolarGo tells me that I have 2.08 kW coming from the roof, and 1.53 going to the battery. The battery is still charging. At 8:35 the grid comes back. According to current load shed schedules, the next useful test slot is 6:00 to 8:30 on Saturday.
  9. Hot water leaks are easily found with a thermal camera. I had one case where the pipe ran under the kitchen floor and was leaking there. Guy with a camera found it pretty quickly. He also took away that nice warm spot we used to stand on on cold mornings
  10. OK. So now, according to the boffins, my system is 100% compliant and they are going to put some pressure on City Power. The last piece fell into place with the application of some labels, like this one affixed to the cover over the meter and the municipal breaker. Others were placed on the main DB (Warning! This equipment is supplied by more than one source.), below the main breaker on the DB (Point of utility connection) and on the AC DB for the inverter under the change over switch (Point of Generator Connection). Now we wait for City Power to test. Apparently this includes earthing, checking for anti-islanding, and timing how long the inverter takes to reconnect on restoration of grid supply (this should not be instantaneous).
  11. So this morning we have no grid since 7:00 and lots of sunshine. I changed from general mode to economical mode at 8:35 or so. Then the grid came back at 8:40. Meh. This is not in the interests of scientific research. But clearly it was charging from PV whilst the grid was down and the system was in general mode.
  12. Whatever you do, and whilst you're doing it, get some good insulation on the hot pipes and the geyser itself. See above. I run my heat pump at 6:30 and 12:00. It seldom runs longer than 30 minutes. So by 12:30 it will have hit 60 degrees and stopped. It is still in the mid to high 50s when the wife showers at 20:00 or so.
  13. Not me. I have experience of only one brand: Kwikot. This was what was recommended to me. I had no idea about what was good and what wasn't, but it was pointed out to me that if I go for a local brand, spares availabity and support will be better. Though the installer did the early support, and I haven't needed spares. I would have recommended the guys who did mine over a decade ago, but they aren't around anymore. There is some simple maintenance that needs doing at regular intervals. Cleaning the strainer. More often clearing leaves/twigs/dead bugs out of the grills. I had mine regassed a couple of years ago. This was not expensive. The feeling on this forum was that I must have the word "sucker" on my forehead because unless there's damage to the pipes or the heat exchanger, the system won't lose gas. You size the heat pump according to the geyser. If you are going to pre-empt a later second geyser, then you will have to massively over spec the pump you buy now. There's a saving. The heat pump uses a far more efficient method of heating water. So it can be, and it is, faster while drawing less power. NB! Mine is limited to 60 degrees. It won't go higher. So if you have people who like a good scalding, then the heat pump might not be for your household. But really, 60 is plenty, you just don't use the cold tap. As an aside, we have flow restricting shower heads. They actually don't feel restricted at all because of some way they have of generating lots of individual little jets. With any type of water heating that is going to mean less hot water being taken from the geyser, so less work for the geyser to do. I have been using this brand for ... maybe 20 years now. When we moved house we moved the shower heads with us (we took them off before the show day, so the buyer still got what they saw). Depends on the rest of your loads, but I run mine on the essential side (I don't have the smart port thingy). I run mine twice a day: 6:30 and 12:00. This used to be 5:00 and 12:00, but that made little difference. It uses about 1.5 kW. At 6:30 there is not much else happening so we get away with it. You need to have enough left in your battery. So it's the old game of balancing your loads, moving them around using timers, and trying to get the household to work with the system. 12:00 there is more going on in the house. But I try to keep (EG) the dishwasher for earlier in the day. But I have a much lower current limit than you do, you can have far more load at any one time than I can.
  14. OK, so here is PV (blue), load (yellow) and SOC (green) for my system today PV was very variable and downright poor early in the day. Power was out until 9:25 and then from 12:00. So two sections of this graph are of interest to us 1) 8:35 with the grid out, we see PV considerably greater than load. As this brief sunny period was happening, I was busy switching the system into economical mode. PV tails off slowly over the next 20 minutes, but it was gloomy and we don't see an immediate shift to just tracking the load. 2) 12:00 the grid goes down for the 2nd load shed of the day. But look what happens next. PV is still quite variable (or demand from PV is), but it carries on charging the battery. What I don't have time to do is look out of my window to see how the sun is shining, but definitely the system, in general mode now, carried on charging after the grid went down. So two possibilities 1) 2121E has made a difference and/or 2) The problem is in eco mode The latter is not clear to me yet. There's a voice in my head (shut up! You all have them ) saying that the way I use eco mode to charge between 15:00 and 16:00, the system doesn't know for the rest of the day if it should be charging or not. I need some more data, but I'm skittish. Twice in the last week the power has stayed off after load shedding. Once for 1 hour, on the other for 10. So if the weather is not so lekker, and even then, I like to get some charge into the batteries because you don't know when the power is going to come back.
  15. Yep. https://www.timeslive.co.za/news/south-africa/2024-02-11-electricity-minister-says-load-shedding-expected-to-ease-by-midweek/
  16. And boy, Sunday is not good. I hope we at least get some rain out of the deal.
  17. You can, when there is grid. Usually the DB is split up into non-essential and essential loads, with the non-essentials not being supported when the grid is down. So if your geyser is on one of those circuits, it can use grid when there is grid.
  18. Not a safe assumption. Do you not have access to some tool that gives you a graph like this one from my system? They are not all exactly like this, but something similar. You can see it tracing load (yellow line), power in or out of battery (purple) and battery's state of charge (green). The left of the graph is midnight. The house is running off of the battery. A quick check shows a low of 110W, a high of about 350. This is the house ticking over at night. WIFI, outside lights, fridges, stuff on stand by, security system. Anyway, my point is that the load is not constant at night. Mine doesn't fluctuate a lot, but it is not constant. OK... your battery has a capacity of 5.12 kWh (per the link you shared). 204 W per hour (assuming that is the average load) gives 1.02 kWh in 5 hours. So you should be losing about 20% every 5 hours - simple arithmetic. 4% an hour IF the average load is 204W, but we can't be sure of that. I lost about 7% over 4 hours, but my battery is double yours. So I can back calculate to an average of 175W. Now your tale above shows a 62% lost over... it's not clear what period of time. We know that the battery was at 79% when charging stopped because the grid went down. But even if we assume 79% at 02:00 then you were discharging at 20% an HOUR (02:00 to 05:00) to get to 17% by 5:00, five times the rate if the average was 204W. So something has to give. Either you are using a lot more than you know/expect at night, or some part of your system is not in good shape. NB! The inverter itself will account for some of the load. Converting 50V DC to 230V AC is not a 100% efficient matter, and also the inverter is going to use some electricity just to keep itself up and running. So we need to understand what the loads truly are. Either you can work a night shift monitoring the system and capturing numbers into a spreadsheet, or you need a tool like the one I show. Between you and the installer, one of you should have access to that data. Check that. If you see much higher loads than you expected then you can investigate. Get that data. See what loads are active during the night, then you can make better judgements and decisions. Ask the installer how possible it is that the geyser is getting power from the battery.
  19. OK... I don't understand those stats. "Residual energy demand", "Contracted energy demand", what that? Otherwise I don't see good news there. If I read correctly then demand on the grid is down (but by a little or a lot, the article doesn't give much context) and yet still Eskom struggles. Interesting that the apparent capacity of rooftop solar is significantly greater than the IPPs that have come on line.
  20. Me again. At my previous home we had a solar geyser. It's been some years now. I don't think it was evacuated tubes, it had some way of using the temperature of the water to circulate it through the panels. The geyser was on the roof. This didn't work so well for me in the mornings. In the afternoon, in the summer, it could get really hot. I wouldn't like to let little kids control that hot water. Into the evenings we had hot water. What we have now suits our routines better. We had the heat pump installed well before the solar, and it definitely is a money saver. At first we just let do it's own thing, then we started using the timer functions it has to give it just two runs a day. At the old house I had to heat from Eskom to get a morning shower (there's another story here about times and ripple switches), so that solar geyser was a money saver too, but if I'd been more flexible it could have saved us more. Also we would have had to get the housekeeper on side and tell her she can have hot water from whatever time but not in the early morning. I mention all of this because it shows again how you need to try to dovetail your own needs with the sun when do you solar stuff. Or you have to decide on trade offs.
  21. Good on him for doing the analysis and trying to find a best fit solution. I have heat pump, and I run it on the backed up side of my system. As already pointed out, the pump is faster and more efficient than an element. Mine draws about 1.7 kW, but at this time of year it runs for maybe 30 minutes in the morning to get to 60 degrees (it won't allow a higher temperature). We also have lots of extra insulation on the geyser, and cladding on the hot water pipes. Currently it switches on at 6:30 in the mornings and is set to turn off again at 7:15 but hardly ever runs that long. It then comes on again at midday, and is allowed much more time but, again, rarely exceeds 30 minutes. It doesn't matter if the sun is shining or not at run time (I don't get a lot of PV at 6:30) but, of course, if we have a run of overcast days then eventually I have to charge the battery from the grid and that point you could say it's cost me money. We are just two people. I shower in the morning, the wife likes to shower in the evening, and at 20:00 the water is still plenty hot enough. So we would do better than solar, I think, for early morning showers. And if the sun doesn't shine at all you'll have to fall back on Eskom. We try to do as much as possible between 9:00 and 16:00, and really in the morning. We run the dishwasher during the day, the pool pump runs during the day, we try to do everything with appliances during the day. Etc. Because of this there is usually 60 ish % of the battery (10 kW/h) left at 6:00, and that gives me enough to run the pump and then start recharging a little later in the morning. A lot of living with any form of powering stuff from solar comes down to routines. You literally have to make hay whilst the sun shines. So I'd look at your routines and your usage (electricity and water) and see if there's anything you can do to optimise your current situation before you start spending money. What can you change? Does it suit you to change? It's all trade offs, and we all weigh things differently. There's a right solution for you and your family, but there's no one right solution. NB! I have a second, rarely used, geyser. I can heat that up in the afternoon on a sunny day. It's not on the backed up circuits. The element was downgraded (I think it's 2kW) and it usually takes a bit less than 2 hours (thermostat is set to 60). That would give me a lot more hot water in the afternoon, and most days I can do it with PV power as the battery is usually charged by about 11:30. It's not as efficient as the heat pump, but it still doesn't cost me much as I'm using free energy.
  22. OK... I googled the name that you gave - Ever Start - and I got this site https://www.ever-start.co.za/ So apologies to the store (with the same name) that you were referencing
  23. OK... I need to pay more attention. Thanks,
  24. Oh it's an Eskom problem all right. They can't meet demand. It's just that when the PV is pumping, their problem gets smaller. For which they get no credit. It does seem to me that there is a correlation between load shedding stage and the weather.
  25. They advertise a Hubble AM-2 for R40k. 2 minutes googling found me the same battery at 38k from Leroy Merlin and 33k from Takealot. Their price on the Rentech UPS can also be beaten. I quickly shaved 6k off the price of the Growatt. Takealot beat or matched every price here, and their price includes delivery. So the wrong kind of amazing for me.
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