Scubadude Posted November 27, 2021 Share Posted November 27, 2021 (edited) OK, as I posted elsewhere I was looking out for a Black Friday deal for a "8kW System" - hate that way of thinking because I don't believe 8kWp PV, 8kW inverter and 8kWh storage is a balanced system for most users - almost certainly it will be way heavy on panels and light on storage, resulting in lots of unused energy. I got lucky with a super deal, fully installed with COC essentially for a little less than I could buy the main components in the retail market. In the end, my selected equipment reads like this: 14 x Canadian Solar CS3W-455MS HiKu Super High Power Mono PERC modules - that is 6.37kWp but with my roof angle of 7° I will start with a 8 or 10% drop off the bat 8kW Deye SUN-8K-SG01LP1 -US/EU Inverter 2x Shoto SDA10-48100 5.12kWh LiFePO4 batteries for 10.24kWh of storage. I think I'm still panel-heavy and storage-light but I do believe it is better balanced than a typical "8kW system". And a third battery is only a card swipe away... My installation started on Thursday, and will only be completed later today (Saturday), but here are some early pics: Before, looking true north. Stoep roof slopes 7° to north. Pool heater tubes more or less where the panels will go. Before, looking west. Notice palms that can only be touched at risk of permanent solitary confinement. Will keep them trimmed. Pool heater is history Mounting structure installed, panels being laid down First panels being installed. Finicky work this. All treehugger ... solar geyser framed by solar panels Most panels up - looks better than the pool heater tubes! All panels installed - looking west Another one looking east - roof looking tatty and needs some paint. Nice winter project coming up. All panels in looking east Surprise! The laundry room where the inverter will go has drywall cladding over face brick. To offset the inverter to an effective flush mount required some nifty brackets. Mecano courtesy of Builders. Only minor mods required. The loose end was tack welded after the pic was taken. Cutout for inverter done, brackets fitted. End day 1. Lesson for the day: Get your roof checked by a professional contractor before starting. The guys fastened some of the loose sheets but a coat of paint beforehand would have been ideal. Inverter, AC breakers (left), DC breakers (right), fusebox (below) and batteries installed. Should have been mounted 200-300mm higher to clear the counter top I want to install - will have to make a cutout for the fuse box. Inverter and associated hardware End day 2. Batteries comms tested. Unseen work was to connect the PV strings and bring the DC cable to the other side of the house, which required roof sheets to be lifted. Lesson for the day: do not attempt DIY for a project of this size if it is your first one - bound to cost more in time (and posisbly real money) when done. So on to final wiring and commisioning today! Edited November 28, 2021 by Scubadude added detail Yellow Measure, Gerrie, conradl and 1 other 3 1 Quote Link to comment Share on other sites More sharing options...
Yellow Measure Posted November 27, 2021 Share Posted November 27, 2021 Interesting installation, no install is ever the same. Quote Link to comment Share on other sites More sharing options...
Antonio de Sa Posted November 27, 2021 Share Posted November 27, 2021 3 hours ago, Scubadude said: OK, as I posted elsewhere I was looking out for a Black Friday deal for a "8kW System" - hate that way of thinking because I don't believe 8kWp PV, 8kW inverter and 8kWh storage is a balanced system for most users - almost certainly it will be way heavy on panels and light on storage, resulting in lots of unused energy. I got lucky with a super deal, fully installed with COC essentially for a little less than I could buy the main components in the retail market. In the end, my selected equipment reads like this: 14 x Canadian Solar CS3W-455MS HiKu Super High Power Mono PERC modules - that is 6.37kWp but with my roof angle of 7° I will start with a 8 or 10% drop off the bat 8kW Deye SUN-8K-SG01LP1 -US/EU Inverter 2x Shoto SDA10-48100 5.12kWh LiFePO4 batteries for 10.24kWh of storage. I think I'm still panel-heavy and storage-light but I do believe it is better balanced than a typical "8kW system". And a third battery is only a card swipe away... My installation started on Thursday, and will only be completed later today (Saturday), but here are some early pics: Before, looking true north. Stoep roof slopes 7° to north. Pool heater tubes more or less where the panels will go. Before, looking west. Notice palms that can only be touched at risk of permanent solitary confinement. Will keep them trimmed. Pool heater is history Mounting structure installed, panels being laid down First panels being installed. Finicky work this. All treehugger ... solar geyser framed by solar panels Most panels up - looks better than the pool heater tubes! All panels installed - looking west Another one looking east - roof looking tatty and needs some paint. Nice winter project coming up. All panels in looking east Surprise! The laundry room where the inverter will go has drywall cladding over face brick. To offset the inverter to an effective flush mount required some nifty brackets. Mecano courtesy of Builders. Only minor mods required. The loose end was tack welded after the pic was taken. Cutout for inverter done, brackets fitted. End day 1. Lesson for the day: Get your roof checked by a professional contractor before starting. The guys fastened some of the loose sheets but a coat of paint beforehand would have been ideal. Inverter, AC breakers (left), DC breakers (right), fusebox (below) and batteries installed. Should have been mounted 200-300mm higher to clear the counter top I want to install - will have to make a cutout for the fuse box. Inverter and associated hardware End day 2. Batteries comms tested. Unseen work was to connect the PV strings and bring the DC cable to the other side of the house, which required roof sheets to be lifted. Lesson for the day: do not attempt DIY for a project of this size if it is your first one - bound to cost more in time (and posisbly real money) when done. So on to final wiring and commisioning today! I see a water valve quite close to the electrical installation... Is this allowed? Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 27, 2021 Author Share Posted November 27, 2021 2 hours ago, Antonio de Sa said: I see a water valve quite close to the electrical installation... Is this allowed? I seem to recall the main DB may not be closer than 1m from a water point. This is not the main DB and not a water point. So I think we'll be OK. Will check with the electrician when he comes for the COC. Antonio de Sa 1 Quote Link to comment Share on other sites More sharing options...
Pumba Posted November 27, 2021 Share Posted November 27, 2021 8kW inverter; I would have gone 9kW on panels (always better to go higher on pv power) and those palm trees are going to cut your sun off for quite a few hours in the day. Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 27, 2021 Author Share Posted November 27, 2021 (edited) I'm sorry but I don't get the obsession with maxing out on panels. We average 30 units per day in summer, 40 in winter. Slapping on more panels will give next to zero benefit. Edited November 27, 2021 by Scubadude StepbyStep 1 Quote Link to comment Share on other sites More sharing options...
Bobster. Posted November 27, 2021 Share Posted November 27, 2021 8 minutes ago, Scubadude said: I'm sorry but I don't get the obsession with maxing out on panels. We average 30 units per day in summer, 40 in winter. Slapping on more panels will give next to zero benefit. I think the thinking is that you'll do better on overcast days. My system (12 panels) works fantastically on a bright day. On a day like we're having today in Johannesburg it is less performant. Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 27, 2021 Author Share Posted November 27, 2021 D-day! Signs of life ... Inverter on DC power. System is functional but not yet tied in with the grid Batteries connected up and working as it should Minutes after go-live ... miserable day to be cutting the ribbon on a solar system, but even with a paltry 600W coming off the roof it is powering the house in Saturday afternoon mode and putting a bit into the batteries. Lesson learned today: installers do not necessarily know how to properly configure the inverter. Need to read some manuals and watch some youtube videos. Solarman Smart app ... I had the normal one installed but like this interface better. A full 1.5kWh produced today! 2nd lesson for the day ... after paying for a solar system whatever is generated feels like free electricity! First usage data - I installed the app after production stopped. Hope to see lots of blue tomorrow! Some nice generation and consumption metrics. Will be watching these with a hawk's eye in the coming days and weeks. Tomorrow I'm starting the snag list and will test what is connected where - that is the one thing I did not check during the installation. Also on the agenda tomorrow is to optimise the inverter settings as best I can. Yellow Measure and JoeSlow 2 Quote Link to comment Share on other sites More sharing options...
Yellow Measure Posted November 27, 2021 Share Posted November 27, 2021 50 minutes ago, Scubadude said: D-day! Signs of life ... Inverter on DC power. System is functional but not yet tied in with the grid Batteries connected up and working as it should Minutes after go-live ... miserable day to be cutting the ribbon on a solar system, but even with a paltry 600W coming off the roof it is powering the house in Saturday afternoon mode and putting a bit into the batteries. Lesson learned today: installers do not necessarily know how to properly configure the inverter. Need to read some manuals and watch some youtube videos. Solarman Smart app ... I had the normal one installed but like this interface better. A full 1.5kWh produced today! 2nd lesson for the day ... after paying for a solar system whatever is generated feels like free electricity! First usage data - I installed the app after production stopped. Hope to see lots of blue tomorrow! Some nice generation and consumption metrics. Will be watching these with a hawk's eye in the coming days and weeks. Tomorrow I'm starting the snag list and will test what is connected where - that is the one thing I did not check during the installation. Also on the agenda tomorrow is to optimise the inverter settings as best I can. Congratulations! Scubadude 1 Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 27, 2021 Author Share Posted November 27, 2021 8 hours ago, Bobster said: I think the thinking is that you'll do better on overcast days. My system (12 panels) works fantastically on a bright day. On a day like we're having today in Johannesburg it is less performant. So let me get this straight ... in order to avoid low yield on relatively few bad solar days, add more panels which will compromise yield on the majority of good solar days? For a grid tied system. Makes very little sense other than for bragging rights. Quote Link to comment Share on other sites More sharing options...
TimCam Posted November 27, 2021 Share Posted November 27, 2021 2 hours ago, Scubadude said: D-day! Signs of life ... Inverter on DC power. System is functional but not yet tied in with the grid Batteries connected up and working as it should Minutes after go-live ... miserable day to be cutting the ribbon on a solar system, but even with a paltry 600W coming off the roof it is powering the house in Saturday afternoon mode and putting a bit into the batteries. Lesson learned today: installers do not necessarily know how to properly configure the inverter. Need to read some manuals and watch some youtube videos. Solarman Smart app ... I had the normal one installed but like this interface better. A full 1.5kWh produced today! 2nd lesson for the day ... after paying for a solar system whatever is generated feels like free electricity! First usage data - I installed the app after production stopped. Hope to see lots of blue tomorrow! Some nice generation and consumption metrics. Will be watching these with a hawk's eye in the coming days and weeks. Tomorrow I'm starting the snag list and will test what is connected where - that is the one thing I did not check during the installation. Also on the agenda tomorrow is to optimise the inverter settings as best I can. Welcome to the solar family. In the coming days and weeks you will really appreciate the system when load-shedding returns, and has zero effect on your household. 2 hours ago, Scubadude said: First usage data - I installed the app after production stopped. Hope to see lots of blue tomorrow! The satisfaction of seeing the "blue" rise every day as your "power station" works for you is great. Enjoy your system, and all the tweaking. Scubadude 1 Quote Link to comment Share on other sites More sharing options...
Yellow Measure Posted November 28, 2021 Share Posted November 28, 2021 2 hours ago, Scubadude said: So let me get this straight ... in order to avoid low yield on relatively few bad solar days, add more panels which will compromise yield on the majority of good solar days? For a grid tied system. Makes very little sense other than for bragging rights. Why will it compromise yield on the majority of good solar days? That which does not get used on good solar days does not get generated. Yes, it's potential waste, but far better than watching production anxiously on a rainy day, wondering if you have enough light to charge batteries, and service loads, and whether the wife & kids will be able to have a warm bath tonight or tomorrow morning. It's days like this that can turn one into a nagging power nazi, constantly moaning at family members for making toast and using the microwave. I personally started out with 4.56kWp, and it was great, but I soon realised that life would be so much more comfortable with more. The MPPTs also far more efficient at higher voltages. Today my worst power output ever was at around 14H30. For about 10m I barely got 0.22kW out of my North-facing 26 degree 6.08kWp array. that's around 3.6%, and my batteries were at 65%. For me, it has absolutely nothing to do with "bragging rights". One installs what one is comfortable with, both in terms of usage and budget, in order to meet objectives. I am pretty sure that after one or two months you will come to a similar conclusion. Don, Barezzi, Leshen and 1 other 4 Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 28, 2021 Author Share Posted November 28, 2021 (edited) 4 hours ago, YellowTapemeasure said: Why will it compromise yield on the majority of good solar days? That which does not get used on good solar days does not get generated. Yes, it's potential waste, but far better than watching production anxiously on a rainy day, wondering if you have enough light to charge batteries, and service loads, and whether the wife & kids will be able to have a warm bath tonight or tomorrow morning. It's days like this that can turn one into a nagging power nazi, constantly moaning at family members for making toast and using the microwave. Depends on your objective I suppose. If it is to be energy independent then yes. But if it is to save money while beating loadshedding those extra panels push up your LCOE quite a bit, diluting, not enhancing, the economic benefit of the system. I would happily use the grid to charge up the battery if needed - we still have Eskom more than we don't. Heck I could even wire in my 6.5 kVA generator and use that like we did before we had solar. I should have been clearer ... I meant performance not yield. Chasing production on miserable days is a pipe dream. So yesterday I got 600W from the roof. Even if I doubled the panels to 12kWp I would only gain another 600W for 5 or 6 hours. So 3kWh more at an additional cost of .... 14 x R3500 = R 49000. While increasing the LCOE of every single Wh ever generated by a whopping 49000/125000 = 39.2%!!! I could get that same energy by wiring in my generator for what? R3000. And then run it for 30 minutes using around 1 Liter of petrol. Sounds a million times more cost-effective to me. Or just pay Eskom the R5 and be done with it. Edited November 28, 2021 by Scubadude Maths Yellow Measure, GreenFields, Barezzi and 1 other 4 Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 28, 2021 Author Share Posted November 28, 2021 Also ... I started out with a larger aray than yours off the bat ... So guess I have the bragging rights then Yellow Measure 1 Quote Link to comment Share on other sites More sharing options...
Nitrious Posted November 28, 2021 Share Posted November 28, 2021 (edited) your winter solar generation will drop, as will shading from the tree's/palm increase and loads will increase as they do in winter. The advise given on extra panels isn't wrong, its up to you to assess if its relevant in your case, but its given with good will, and experience. I'm in the "rational" extra panels group and sure there's a point where adding more doesn't make sense for those odd rainy days but keep the above in mind going forward. I do get your point however, solar is an average on yield and savings, and it makes sense to put those extra few units on the grid rather than upsize ridiculously to save those few units. Maybe also consider a heat pump, they really do drop the power consumption requirements. As for bragging rights, I don't believe in them, what's even the point. My approach was to buy every thing second hand except panels, even my heat pump is second hand, it all works great, and capital input cost dropped substantially, even self installed. So you want to talk ROI, that's about as good as it gets. Edited November 28, 2021 by Nitrious Scubadude and Yellow Measure 2 Quote Link to comment Share on other sites More sharing options...
Bobster. Posted November 28, 2021 Share Posted November 28, 2021 8 hours ago, Scubadude said: So let me get this straight ... in order to avoid low yield on relatively few bad solar days, add more panels which will compromise yield on the majority of good solar days? For a grid tied system. Makes very little sense other than for bragging rights. Well yesterday in Jhb my system produced just 5.3 kw/h. Even with turning a lot of stuff off it's hard to get through 24 hrs on that. If I turned everything off I might have got the battery charged. I had to draw power from the grid. The flip side of that coin is that on a clear sunny day I actually have PV to spare. My battery is charged by 11:30 and after that the system derates the panels and draws just what it needs to service the load and keep the battery topped up. I don't generate all the PV I could because there's nothing to do with it. So it depends on your aims. If you want to not pay a cent to Eskom then you need more panels and more battery than I have. It's easy to generate sufficient power for a day in one day on a sunny day. When it's overcast then it's harder to find that power. When I have a run of poor weather then I have to resort to grid, but although I can do that I increasingly resent doing so. Don, Yellow Measure, Scubadude and 1 other 4 Quote Link to comment Share on other sites More sharing options...
Nitrious Posted November 28, 2021 Share Posted November 28, 2021 Well EV's are on their way, so what works today may well not work once the move away from ICE vehicles begins, I've begun planning for around 24x 450w total panels for that occurrence. Lets not forget water, another rapidly increasing cost, so borehole is on the way, yet another energy requirement to be added, along with air to water for the kitchen. Result would be never paying for water, lights or fuel ever again. Worth it? definitely, but maybe I'm just crazy. Yellow Measure and Solardad 2 Quote Link to comment Share on other sites More sharing options...
Gerrie Posted November 28, 2021 Share Posted November 28, 2021 10 hours ago, Scubadude said: Tomorrow I'm starting the snag list and will test what is connected where - that is the one thing I did not check during the installation. Also on the agenda tomorrow is to optimise the inverter settings as best I can. Nice setup, sure you’ll find lot’s of things over the next few weeks you could tweek and play with, I went through my manual about four times to look for that one thing I could of missed or don’t understand and learnt something new every time What was the final decision on strings arrangement? I am also curious of heat buildup that can be generated between the panels and the roof. Would you be so kind as to give an opinion over the next few days or weeks if their is an increase or decrease in temperature in your home. You probably do have good insulation and it might not be noticeable at all but I’m always curious about this when panels are payed on a roof. Scubadude 1 Quote Link to comment Share on other sites More sharing options...
Gerrie Posted November 28, 2021 Share Posted November 28, 2021 12 minutes ago, Nitrious said: yet another energy requirement to be added And then come school holidays and now it’s big screen TV’s, X boxes, gaming pc’s that never get switched off, suddenly I need to rethink my batteries and panels Yellow Measure and Nitrious 2 Quote Link to comment Share on other sites More sharing options...
Bobster. Posted November 28, 2021 Share Posted November 28, 2021 (edited) 4 hours ago, Scubadude said: Depends on your objective I suppose. If it is to be energy independent then yes. But if it is to save money while beating loadshedding those extra panels push up your LCOE quite a bit, diluting, not enhancing, the economic benefit of the system. This is true. My wife just got agitated because a friend of hers has solar power and is posting that her electricity bill (COJ prepaid) is down to only R1000 a month. I said well if her bill used to be R3000 a month and the system gets her through loadshedding then that's a good ROI. I am increasingly coming to believe that some folks really are paying multi-K electricity bills each month. This is strange to me because before we switched to solar we were using on average about 400 kw/h a month (heat pump, gas hob), which is still under a grand at current tariffs. But some folks do use a lot more, even if I don't understand how. We don't all have the same circumstances, and a good outcome for one might be a poor outcome for another. If I were paying 1K a month for electricity then I'd think I'd wasted my time and money with solar, but others might think that a win. Edited November 28, 2021 by Bobster Sppeling Quote Link to comment Share on other sites More sharing options...
Nitrious Posted November 28, 2021 Share Posted November 28, 2021 (edited) 33 minutes ago, Bobster said: This is true. My wife just got agitated because a friend of hers has solar power and is posting that her electricity bill (COJ prepaid) is down to only R1000 a month. I said well if her bill used to be R3000 a month and the system gets her through loadshedding then that's a good ROI. I am increasingly coming to believe that some folks really are paying multi-K electricity bills each month. This is strange to me because before we switched to solar we were using on average about 400 kw/h a month (heat pump, gas hob), which is still under a grand at current tariffs. But some folks do use a lot more, even if I don't understand how. We don't all have the same circumstances, and a good outcome for one might be a poor outcome for another. If I were paying 1K a month for electricity then I'd think I'd wasted my time and money with solo, but some might think that a win. Extremely well said, I do suspect there are more than a few "installers" out there that don't spec the requirements properly or provide substandard equipment as premium and pocket the difference. At the same time available budget comes into play, and so a compromise is reached, so its not perfect, but its what fitted the bill so to speak. I do also feel that not enough people look to reducing appliance load first, aka as with yourselves, going the heat pump, gas hob route before installing a solar system, thus reducing the size and cost of the system needed. That R1000 per month could well be the geyser and kitchen load left on the grid and easily rectified in the future. Edited November 28, 2021 by Nitrious Quote Link to comment Share on other sites More sharing options...
Bobster. Posted November 28, 2021 Share Posted November 28, 2021 1 hour ago, Nitrious said: I do also feel that not enough people look to reducing appliance load first, aka as with yourselves, going the heat pump, gas hob route before installing a solar system, thus reducing the size and cost of the system needed. Indeed. And I think a lot of folks could save themselves some good money without even having to replace things - just by taking a few precautions and applying a little discipline. I've been fighting that fight for years now, starting off with replacing incandescent globes with CFLs, then checking geyser thermostats, then getting a solar geyser and so on. You see that bill come down over the months. You have a little extra cash. Also in the current house (which has heat pump rather than a solar geyser) I switched to pre-paid, another saving (and that also does away with the infamous "estimation" readings that we get in Johannesburg). The real problem with all of this though is that solutions that require you to buy stuff mean spending money now to save money in the long term, and not everybody has that money. But see my opening point - there is money to be saved just by being careful. As you say, one can only do what is within one's budget. Even going pre-paid cost me some money up front, but I recovered that within about 4 months. MdF 1 Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 28, 2021 Author Share Posted November 28, 2021 (edited) 8 hours ago, Gerrie said: Nice setup, sure you’ll find lot’s of things over the next few weeks you could tweek and play with, I went through my manual about four times to look for that one thing I could of missed or don’t understand and learnt something new every time What was the final decision on strings arrangement? I am also curious of heat buildup that can be generated between the panels and the roof. Would you be so kind as to give an opinion over the next few days or weeks if their is an increase or decrease in temperature in your home. You probably do have good insulation and it might not be noticeable at all but I’m always curious about this when panels are payed on a roof. Thanks Gerrie, We went with 2 strings of 7 panels ... top row plus one from the bottom in the one string, and the rest of the bottom row on the second string. I suspect the stoep doesnst have ceiling insulation and the shading of the panels may make it cooler in all seasons. Will report back when I can. Edited November 28, 2021 by Scubadude terrible grammar and spelling Gerrie 1 Quote Link to comment Share on other sites More sharing options...
Scubadude Posted November 28, 2021 Author Share Posted November 28, 2021 2 hours ago, Nitrious said: I do also feel that not enough people look to reducing appliance load first, aka as with yourselves, going the heat pump, gas hob route before installing a solar system, thus reducing the size and cost of the system needed. Very true ... we peaked at R4000 per month in winter 2020. What we (family of 6) have done to reduce load so far: LED lights everywhere, including possibly excessive yard lighting as a security measure Gas hob 300Ltr EVT solar geyser, with Geyserwise controls on this and the remaining 200Ltr geyser Foregoing the use of aircons and heaters, using clothes drier very sparingly Wife sorting laundry so underwear, sportswear, pajamas and towels are folded without ironing Using the Weber instead of the oven for cooking However we still average 25 (lowest in summer) to 42 kWh/day (highest in winter). My expectation is that soalr will take care of 2/3 of that in the worst months. Antonio de Sa 1 Quote Link to comment Share on other sites More sharing options...
isetech Posted November 28, 2021 Share Posted November 28, 2021 (edited) I have customer who have bills which range from R360 per month to R 18 000 per month (these are just the domestic bills) There is no complicated maths involved ... throw in a 15 % and then another 15 % electricity tariff increase ... if your bill was R18000.00 last year in June ... this year in November ... your bill will be R23805.00 ... fitting a geyser timer for example is not going to reduce the bill to R2000 per month. If 80 % of your consumption is between 6 pm and 6 am ... installing a roof full of solar panels at a cost of over R100k is also not going to reduce your bill to R2000 per month. It seems people find it difficult to understand that just doing one thing will not change everything. The bottom line ... it is not as simple as just fit solar and suddenly all your electricity tarrifs go to zero. What I have found ... most people dont want a lifestyle change they just want an easy solution. With regards to the comment about the valve ... I dont see a problem ... no water under "normal" operation ... if anything it would be the tap below the installation that would be the problem ... but once the counter top is fitted ... it shouldnt be an issue. The other thing to consider ... the synsynk inverter an IP 65 rating and the DB's look like they have an ip 65 rating (could be less) but I dont know ... I am sure the person issuing the COC will take all that into consideration. The little knowledge I have gained since scratching around in PV field ... anything over a R5000.00 electricity bill ... installing solar is a wise move and you should get some form of ROI ... unless of course you get ripped off with a off grid backup system. Edited November 28, 2021 by isetech Quote Link to comment Share on other sites More sharing options...
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