PB15 Posted April 10, 2022 Posted April 10, 2022 Hi All, I have been reading most of the discussions here for last couple of months and now finally made up my mind on the installation. I want to achieve the following and reduce the electricity bill 1. Power during load shedding 2. Daytime energy savings and 3. Use the battery to meet the evening demand We are a family of 4 (us two and two kids) and a family of two (tenant) in the cottage. I am thinking of the following configuration 1. Sunsynk - 5Kwh 2. Panel - 455w * 12 3. Battery - 7,2Kwh Please let me know if this should be sufficient to generate enough power during the summer and winter. I am aware that I will still have to use grid for the shortfall, but I am hoping it won't be too much. Here is the list of some of the things we use, 2 geysers (200L which I recently retrofitted to solar geyser and 150L), 2 fridges, 2 washing machines, 2 microwaves, 2 electric ovens, 2 toasters, 2 TVs, 2 electric kettles, 2 irons, 2 grinders, pool pump, electric motor, electric fence. Quote
system32 Posted April 10, 2022 Posted April 10, 2022 >Here is the list of some of the things we use, 2 geysers (200L which I recently retrofitted to solar geyser and 150L), 2 fridges, 2 washing machines, 2 microwaves, 2 electric ovens, 2 toasters, 2 TVs, 2 electric kettles, 2 irons, 2 grinders, pool pump, electric motor, electric fence. Q1. What's your monthly & daily kWh usage? Q2. Have you made your home efficient? Q3. Which direction(s) (North or East+West) will the panels be installed and what angle? Normally with a smaller inverters, you need to split the DB into essential and non-essential loads. Q4. Which appliances will you run on the "Essential Load" (Will stay on during Load Shedding). If you have excess solar, you can use a simple timer to heat your geyser(s) during the day and run your pool motor. AFAIK, the SunSynk 5k can handle more than 5kW pass through (quite a bit more). Essential loads will draw power from the battery at night down to a programmed SoC, then switch to grid. In the event of load shedding essential loads will continue on battery until a programmed shutdown SoC is reached. Non essential loads (connected on grid side) will still be powered by excess solar during the daylight up to 5kW. Quote
Kalahari Meerkat Posted April 11, 2022 Posted April 11, 2022 8 hours ago, system32 said: Non essential loads (connected on grid side) will still be powered by excess solar during the daylight up to 5kW. Assuming the grid is up, when the grid is down, so will be the non-essential loads, whether you have excess power or not... BritishRacingGreen and system32 1 1 Quote
system32 Posted April 11, 2022 Posted April 11, 2022 This thread, similar to your sizing, has some good tips: https://powerforum.co.za/topic/12034-to-buy-a-second-battery-or-not/ Quote
GreenFields Posted April 11, 2022 Posted April 11, 2022 Personal opinion would be to keep the tenant's household only on the non-essential side, with no battery backup, and let them organize their own loadshedding solutions like a trolley with inverter, or something similar. At most maybe just give them LED lighting on backup if you can. The 5kW inverter will be overwhelmed very quickly once everybody tries to turn on their loads. Quote
PB15 Posted April 11, 2022 Author Posted April 11, 2022 Thank you all for the feedback. @GreenFields: You are right. The plan is to split the load in essential and non-essential for both the main house and the cottage. The LEDs and Fridges are considered as essential. I am also planning to change the thermostat 150L geyser in cottage to 2Kw so that it can run on Solar during the day. However the one thing I am not sure about is, can I stop the supply to non-essentials in the cottage when enough energy is not generated especially during winter and on cloudy days as the main house is the primary focus and excess solar energy (non essentials) can be used in the cottage. Quote
PB15 Posted April 11, 2022 Author Posted April 11, 2022 @system32 Q1. What's your monthly & daily kWh usage? [PB] The main house daily usage is about 16Kwh during summer. I am hoping it would be about 60% more in the winter. My 200L geyser is converted to solar. The daily usage in cottage is about 9Kwh during summer. I don't have the stats for winter period but 150L geyser is conventional. Q2. Have you made your home efficient? [PB] The lights are changed to LED, we use gas burner stove. Q3. Which direction(s) (North or East+West) will the panels be installed and what angle? [PB] The panels will be installed in East+South directional. Not sure about the angle. Q4. Which appliances will you run on the "Essential Load" (Will stay on during Load Shedding). [PB] Here is the list of essential appliances and the count. It includes some of the appliances in the cottage. If you have excess solar, you can use a simple timer to heat your geyser(s) during the day and run your pool motor. [PB] The poop pump runs between 10am and 4pm everyday and I am planning to change the thermostats on the geyser to run it on solar (non-essential). Hope this helps. Quote
Scorp007 Posted April 13, 2022 Posted April 13, 2022 (edited) On 2022/04/11 at 5:20 PM, PB15 said: @system32 Q1. What's your monthly & daily kWh usage? [PB] The main house daily usage is about 16Kwh during summer. I am hoping it would be about 60% more in the winter. My 200L geyser is converted to solar. The daily usage in cottage is about 9Kwh during summer. I don't have the stats for winter period but 150L geyser is conventional. Q2. Have you made your home efficient? [PB] The lights are changed to LED, we use gas burner stove. Q3. Which direction(s) (North or East+West) will the panels be installed and what angle? [PB] The panels will be installed in East+South directional. Not sure about the angle. Q4. Which appliances will you run on the "Essential Load" (Will stay on during Load Shedding). [PB] Here is the list of essential appliances and the count. It includes some of the appliances in the cottage. If you have excess solar, you can use a simple timer to heat your geyser(s) during the day and run your pool motor. [PB] The poop pump runs between 10am and 4pm everyday and I am planning to change the thermostats on the geyser to run it on solar (non-essential). Hope this helps. Loads give a guidance but one of the major loads is that pool pump running 6hrs. You will have to make a call if 6hrs is a need or a want when on solar. Luckily it can run during sun periods. Edited April 13, 2022 by Scorp007 Quote
Bobster. Posted April 24, 2022 Posted April 24, 2022 On 2022/04/11 at 5:20 PM, PB15 said: Q3. Which direction(s) (North or East+West) will the panels be installed and what angle? [PB] The panels will be installed in East+South directional. Not sure about the angle. You mention load shedding, so you're in SA. I would hope, then, that the above is a typo. That you mean East and NORTH. I have seen some south facing panels, but that's hardly an optimal orientation in the southern hemisphere. Quote
system32 Posted May 4, 2022 Posted May 4, 2022 On 2022/04/24 at 11:49 AM, Bobster said: You mention load shedding, so you're in SA. I would hope, then, that the above is a typo. That you mean East and NORTH. I have seen some south facing panels, but that's hardly an optimal orientation in the southern hemisphere. The reason to have EAST+WEST facing is that you generate PV solar electricity for longer periods - early morning and late afternoon. I have 2 strings - both facing North. Yesterday (4 May) - PV started generating at about 7h45 and stopped at 16h45 - if the strings were EAST+WEST they would start/stop an hour earlier & later. I would generate less overall PV electricity, but I would have PV electricity for longer period. This has an impact on the size of your batteries. If you selling to grid, then NORTH is probably best. If you have a battery and charging for usage at night, then EAST+WEST probably better. Happy for gurus on forum to correct me and advise. razzor13bt 1 Quote
Bobster. Posted May 4, 2022 Posted May 4, 2022 9 minutes ago, system32 said: The reason to have EAST+WEST facing is that you generate PV solar electricity for longer periods - early morning and late afternoon. You are right, and I understand that. But PB15 mentioned that "The panels will be installed in East+South directional", which seems strange in SA. system32 1 Quote
PB15 Posted June 14, 2022 Author Posted June 14, 2022 Hello Good People I finally got my solar installation done i.e. 5kwh inverter, 4,6kwh panel array and 5kw battery. All the items in the main house are added as essential load. The solar retrofit geyser 4kw element, oven and the appliances in the cottage and domestic room are excluded from the setup. The cottage and domestic room have sub-db and prepaid meters. My day consumption for past 3 weeks is about 10kw including the battery recharge. The panels can generate about 18kw, so I am losing about 8kw each day. I want to add my solar geyser 4kw element and oven as non-essential. Per the installer, the moment I add these two items of the main house, the appliances in the cottage and domestic room will be added as well. Here are some of the settings the installer remotely tried without changing any wiring 1. Add solar geyser and oven on non essential, but in the evening I realised that oven and the hot plate in domestic room was pulling power from battery. 2. The installer then changed something and only the essential load was pulling power from battery as original setting but then the next morning my geyser was taking power from panels first, then battery and lastly from the grid. I also realised that the microwave in the cottage and the hot plate followed the same pattern. I asked the installer to revert the setting again because I didn't want the appliances in the cottage or domestic room to pull power from the battery say about 4pm and I end up having half charged battery for my essential load for the night. Hope I explained it well. The questions I have are as following 1. Is there a way to add just my geyser and oven on the solar as non-essential? 2. If I add the cottage and domestic appliances along with my geyser and oven as non-essential, is it possible to avoid pulling from the battery? It should just be solar and grid for non-essential and solar, battery and grid for essential. I am attaching my system flow chart and the current setting Quote
Scorp007 Posted June 14, 2022 Posted June 14, 2022 As far as I know you cannot split your non essential as they all form part of what is fed from the PV for self consumption without exporting. You can use your timer settings for battery to force the inverter to use grid when you have USE GRID selected. Normally one will set some SOC levels to preserve battery power in case of LS. You can for example discharge the battery to at least have 30% left in the morning as PV will then kick in. With the timer settings you use grid to prevent too deep discharge. Quote
iiznh Posted June 15, 2022 Posted June 15, 2022 (edited) 10 hours ago, PB15 said: 1. Is there a way to add just my geyser and oven on the solar as non-essential? 2. If I add the cottage and domestic appliances along with my geyser and oven as non-essential, is it possible to avoid pulling from the battery? It should just be solar and grid for non-essential and solar, battery and grid for essential. 1. Yes, by changing the wiring in the DB 2. Yes, either all non-essentials pull from the battery or none. Most people elect to supply them only via solar(when available) Essentials and Non-essentials are wired with 2 physically separate wires (and mostly is 2 separate DB boxes) Non essential means that those appliances are connected to the grid circuit, the inverter can send power back up the line with the help of the CT clamp (this power can come from the battery if you choose). If the grid is off (loadshedding) there will be no power. Essentials is one the backed up circuit, and should the grid fail (loadshedding) then those circuits are powered from the battery and will remain on. On the DB, geysers have their own circuit, stove have their own circuit, plugs have their own circuit(s) and lights have their own circuit. You can wire those to either essential or non-essential via physical wire. There is no setting to move something to essential or non-essential Edited June 15, 2022 by iiznh Quote
Scorp007 Posted June 15, 2022 Posted June 15, 2022 @iiznh May be I read question 1 wrong. It seems like the OP wanted only the geyser and oven as non essentials but other high loads that form part of non essentials not to be fed via PV during the day. This then means 3 lots of loads while the inverter only has 2 sets. Quote
PB15 Posted June 15, 2022 Author Posted June 15, 2022 Thank you for the feedback. I have asked the solar installer to come and rewire where necessary. In the meantime, do I have to set a setting in sunsynk work mode 2 in the attached picture? I want to achieve the following as a start (tactical solution for now) 1. Use the battery from 6pm to 6am next morning for essential load. No non essentials; neither main house nor cottage/domestic room. So I ticked 'Limit to Load only' and have setup battery soc as 30%. 2. 6am to 8:30am; battery soc is setup as 80% to avoid non essentials pulling power from the battery and should get it from grid. I think 'Limit to Load only' still works for me here. 3. Now from 8:30am to 3pm, I want to non essentials and essentials to use solar power, battery and grid and I can setup soc as 60%. I think one option is, I untick 'Load to Limit only' setting. But I have to manually do this every day for essential and non-essential to be on solar. 4. From 4pm to 6pm, I want to charge battery and plan to configure soc as 95%. The non-essentials to go the grid for the energy needs. Again if I untick the 'Load to limit only' setting per point 3, I have to tick it again from 6pm to 6am per point 1. I hope I am not complicating my life here and there is a simple answer to handle these scenarios specially point 1 and point 3 which manually ticking or unticking 'Limit to Load only' every day two times. Quote
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