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GreenFields

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GreenFields last won the day on March 28

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  1. Different types of inverters all get sold as "Hybrid" if they can use battery and solar. Not all hybrid inverters are grid-tied inverters that can fully synchronise to the grid and export energy to the utility. Some hybrid inverters are basically off-grid inverters that can draw extra power from their grid inputs. The first type can use a CT clamp to control export power, the second type does not have a use for one.
  2. Not necessarily. One would have to see your graphs of production and consumption and battery power/SOC to be sure, but at this time of the year it could quite easily be that your 4.5kW of panels can produce a maximum of around 3kW at that time of the day. Then if you factor in other loads in the house, and sometimes partially cloudy weather, it can easily be that your system needs to draw on the batteries in-between to keep up with demand. Just making up numbers here. It would be different if you were connected to the grid, because then you could set it up to run from grid while the battery charges. Which way are your panels facing? And where are you located? You could try to start the geyser later, like 11:30-13:30, if the panels are facing North, or even later in the day if your panels are facing more to the West, or if you are living more in the Western parts of SA.
  3. There have been a few posts lately about folks with relatively large inverters relative to a somewhat limited grid supply. Sorry to hijack, this doesn't help your specific case now, but the Sunsynk/Deye hybrid inverters have a peak-shaving function that is supposed to specifically support weaker (/cheaper) grid supplies, limit the draw from the grid, and seamlessly blend in battery power to meet the load. That could be a somewhat elegant solution for those who want to cut costs as above, but not suffer too much disruption.
  4. I think it is important if you are limited to an inverter that is less powerful than the grid. Maybe one of the installers can comment here. My fear is that you may be limited to an 8kW inverter or less just to get a certificate of compliance, as long as you want to be on the grid. But don't quote me on it.
  5. Personal 2c. I think you could get far with just the 8kW Sunsynk and max it out with 10400W of panels, as a minimalist starting setup. I'd suggest the AM5 Hubble batteries rather than the AM2 though. That would be putting the aircons as non-essentials, if you're using as above 1740-2400W per 18000btu. That could provide power for 3-4 inverters at once most of the time. In this setup you'd stay connected to the grid to help you cope with the start-up surges and cloudy spells anyway, but after that the inverter can direct up to 8kW, and charge the batteries above that to 10kW. But if you add in running the pool pump and two heat pumps, say another 1kW plus 2 x 1.25kW, the 8kW would be a bit lightweight to cover that all at once, so you'd either have to upgrade to maybe the 12kW, or else be willing to shuffle the time schedules for aircons versus pool & heat pumps, or be satisfied to buy some in from Eskom. The heat pumps I think are better on AUX/Smart-Load, so you have a backup plan for when the grid goes down, similar to how you'd swap your aircons to fans, but the pool pump could just stick as a non-essential load, and be prepared to run it later when the grid is back. I think the 16kW inverter is a bit much, not needed, especially if you'd have to upgrade your Eskom supply to 80A. I'm assuming it's all single-phase. My gut feeling is a 12kW would be about the sweet spot, and then I'd match it with a Greenrich as a 1.5C battery, in case you'd be interested in going off-grid that'll help you better with surge capacity.
  6. I think you need to give more information about your power consumption in terms of all the devices you're using, and when, or how long, or in terms of kWh consumed per month. If you're staying on-grid, and what size of main circuit breaker have you got? It's quite possible to divert solar power to the aircons by day, and configure it as non-critical loads without battery backup. In this ballpark of Sunsynk inverters you're looking at 48V batteries. You don't have to go to town and be 100% off-grid self-sufficient, there is also a middle ground that you can start with and maybe upgrade later. It is possible to under-size the amount of batteries you've got connected, if you set up and configure it on the inverter, and if you accept the limitations that brings. The 16kW is probably bigger than what most average homes need, most could get by with an 8kW or 12kW. But again, without knowing your actual power usage, it's not really possible to say.
  7. The larger geyser has more hot water in it, so more heat to lose, and a greater surface area over which to lose it. However, the ratio of surface area to volume becomes lower when you go for a bigger geyser, so a bigger geyser will retain heat more easily relatively speaking. One reason why you won't find really big animals on land, they'd struggle to lose heat. A lot depends on your water usage patterns. If you heat up a 150l of hot water to 65 deg, but you only use/need 100l, then you've wasted energy. You could of course lower the temperature on a bigger geyser to maybe 55 deg. Just for re-sale value to the house, better to just go with a 150l as most families will need or expect that size. If your geyser is at 65 deg, the cold water is at 25 deg, and you want to shower at a reasonably warm 45 deg, then you need to mix in equal parts of hot and cold water. You could play around with a water heating calculator here: https://www.spiraxsarco.com/resources-and-design-tools/calculators/water-mixing/water-mixing?sc_lang=en-GB
  8. Just as a high-level thumbsuck, you could be generating around 50-60kWh per day during summer, and your usage may have dropped from 30kWh to maybe 25kWh, due to less heating and lighting needs. There should be a surplus you could sell off if it makes financial sense. Try finding a solar calculator online to give a more accurate projection.
  9. As additional info, the full grid-tied hybrid inverters like Sunsynk or Deye will do all of the above and more. At the lower end of the spectrum, some models of off-grid hybrid inverters may not be able to blend power from different sources, while other models even from the same manufacturer maybe could, but then they might not allow a pass-through from grid above the rated power. Best might be to state which inverter you are interested in buying, check the manual, and ask around from the forum who knows that inverter in detail.
  10. Set the PV priority to "Load Priority," as opposed to "Battery Priority." Move as many loads to daytime as you can. Use "Zero Export to CT" Try the suggested timer settings as below. Time Start Time End Power SOC Grid Gen 00:00 05:00 500 40 05:00 09:00 3000 20 09:00 15:00 5000 100 15:00 17:00 5000 100 X 17:00 19:00 3500 70 19:00 00:00 1000 50
  11. I think you need to be more specific in giving your model of Mecer inverter. They come with different types of charge controllers, and that makes a difference in the panel layout. Otherwise, give a snapshot of the PV input specs on the side plaque of the device. While you're at it, please give the full specs of the PV panels you're using.
  12. Just my 2c. This doesn't make sense. Forget for a moment that the 8kW is a hybrid inverter with a Gen port and battery. In a normal AC-coupling scheme your micro-inverter does not have a Gen port. When the inverter is operating as a micro-inverter does in grid-tied mode (without a battery), the connection is to the Grid port on your 8kW inverter. The Gen-port on the 16kW inverter should then be acting as the controller that sets up the micro-grid by using frequency-shifting to control the output from the micro-inverter.
  13. Okay, so the battery BMS communication seems to be okay. But as said by @Sidewinder, you should re-send pics of the Solar screen once the sun is out and you're generating power. Just set your Max A Charge to 150A. If your installer set the Max A Discharge to 150A, then I assume a charge rate of 150A must be okay. Remember, you're not charging from grid right now, only from panels, but you are limiting your battery to only take in 40A DC at the charge voltage of 55.5V. This is not the same as 40A AC at 230V from Eskom. To get to the Battery setting for Grid Charge, once you're on the first battery screen, press the down arrow on the right-hand side of the screen.
  14. Need clarity here please. Did you set the global charge amps to 40A on the Battery Settings screen as in the image below? I could be wrong, but if this is the case, this may well be the reason for this issue, and you may need to set it higher. If you've got 8.8kW of panels, I'd just set this Max A Charge at around 165A. Then for the Grid Charge, if the council breaker is rated 40A at 230V (9.2kW), and around 1kW of baseload then i'd suggest the charge Amps from grid could be lower, say maybe around 120A. BUT, check with your installer before doing it, and double-check the battery wiring and fuse current ratings if they can handle this before changing anything. OR I could be wrong and need to backtrack. Send the pics anyway. Still think your battery comms could be off, or you may be running in Voltage mode, but just guessing.
  15. Can you post these screens from your inverter: Solar (Solar panel detail page). / Li-BMS screen. / Battery Setting screen. / System Work Mode - Time of use Any chance your battery charge rate is set at 40A.
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