South Easter

I think there is a NRV, but have never investigated in detail. The system is pumped. As long as it works....

My pump also runs when there is a differential of 7° so geyser and collector are never that far apart. Apart from the one instance where a circuit breaker tripped (for a non-pump -related reason) on the circuit with the pump. I have the pump on a different circuit from the geyser so that the pump can still run as an essential load during load shedding. If I recall correctly the collector was around a hundred degrees with the geyser at 60°. But during a sunny day the pump will run every few minutes. I have never timed it exactly, but it could be about 10 minute intervals I think. A sunny day will easily add more then 20° to the geyser temperature. I can't tell you where your problem is, but your system does seem to be underperforming.

Have a similar set up, but am using almost no external power to heat water except on very overcast/rainy days. So I think there is definitely a problem somewhere in your system. Have easily reached 60-65 degrees in the last few sunny days in Cape Town - now with rain and cloud may need some external heating. In summer temperatures are even higher and I occasionally shield some of the tubes. Should not lose more than 3-4 degrees overnight if the geyser is well insulated.

In my quote from the installer CoC and registration with the City of Cape Town were specifically itemized. I held back those two payments (for several months) till those two items were complete. I think an escrow account is a good solution - shows you have the money and are willing to pay.

I take the point on the carbon footprint generated by using Eskom to charge - thus far I have managed to keep it to a minimum and estimate that more than 90% of charging was from solar. But it is still good to have a plan B

I really can't add anymore to what Youda has said - I would classify myself as a novice who understands the basics but essentially still just wants things to work (and I someone else can make them work all the better). I get away with using my system for EV charging as I only need to do small top ups overnight. The slow charging rate then is not so problematic. I have accepted that I will use public charging for larger charges or if I need to top up quickly. There are three DC chargers I know of in Cape Town. They charge at 50 kw per hour (in Europe some chargers already do a lot more). One is in the Gardens Centre, another one at BMW Century City and the third is at Willowbridge (Tygervalley). They can charge an i3 from 0 to 80% in 30 minutes - you can fully charge while shopping. I like Youda's solution 2 but selling it to the CoCT officials will be very very hard as he says....

Maybe my experience as a novel electric vehicle owner will be useful to you. I bought a BMW i3 approximately two months ago. Many reasons for that: my old car was getting on in years, I wanted to reduce my carbon footprint, I wanted to make better use of my solar generating capacity and who can resist the lure of a new big toy... Definitely not a money saving endeavour as yet, but then a hobby does cost. Thus far I am very happy with the car - a completely new driving experience. I am really enjoying it. I run a grid tied/ hybrid solar system (SMA Sunnyboy + Sunny Island) together with 16 kWh of BlueNova batteries. I in fact added an extra 8 kWh to help me charge my vehicle. I have 3.96 kWp of solar panels on the roof. That is near the limit of what I can accommodate in a relatively north facing direction. Being single my daily consumption ran around 8 to 10 kWh prior to having the electric vehicle (I have converted to a solar geyser, gas hob, LED lighting, low-power pool pump et cetera). I could therefore definitely produce more electricity than I was consuming and I wanted to put this electricity to good use. I am at work most of the day, so am actually not able to charge with solar directly except over weekends or if I'm lucky enough to get home before the sun has set. Luckily, my daily commute is around 20 km only. That means I only have to recharge the battery by approximately 2 to 5 kWh on a daily basis, depending if I do any other trips. (It is up and down the mountain!) I am also very lucky in that the shopping centre very near my house (literally two minutes down the road) has recently installed a DC fast charger. I therefore always have a backup option if I need to get the battery full quickly or return from a long trip with an empty battery. Daily charging I manage from stored battery capacity or do over the weekend when I'm at home. The BMW can be programmed to charge immediately or to charge later at set times that you can select. You can also vary the charging current. The standard charger supplied with the vehicle charges at a current of 10 A. You can reduce that I think to a minimum of around 6 to 8 A. With second party chargers you can charge up to 15 A from a standard plug. If you want faster charging rates you need to invest in a wall box or similar equipment. That is of course if you use electricity from the grid. With a standard solar setup I think you will be limited to the slower charging rates (with the current of around 8 to 10 amp) as you will otherwise require a lot of panels and very large inverted to produce for instance 10 kW of power. That of course means that if the battery is completely empty it will take you a very long time to charge. I schedule charging for the early morning hours when there are no other competing demands on the electrical supply. The inverter and batteries can happily supply the required current. This works very well for me and I leave home with a 100% charged battery every morning. Thus far I am simply using the charger supplied with the car and have not felt the need to upgrade to a faster solution, especially since I do have the DC charging backup. My one concern with a totally off grid solution with no battery (and I am definitely no expert) is whether the car's charging system will be happy with a fluctuating power delivery as is often the case with solar production. I am worried that the charging may be interrupted due to the software in the car detecting what it interprets as a grid error when your solar output drops from a passing cloud. Either you would need to use a very low charging current so that your production always exceeds the demand during charging (but then you are basically throwing a lot of potential power away) or you may need to have a system with a relatively small battery that can supplement and keep the power delivery steady. I know that a fair number of consumers in Europe are using solar for charging, but my understanding is that it is mainly in the setting of a grid tied solution. This will of course guarantee a steady delivery of power to the car during the charging process. Just my experiences and thoughts.

I use these covers. Essentially they are piping sawn in half. They fit standard EV tubes and work well. https://www.sustainable.co.za/geyserwise-evacuated-tube-cover-set-of-4.html

Hi I will send you a PM

I had my system installed by NorthFace Solar. They did a good job. Probably on the pricier side as they have recently moved towards using SMA a lot

I have a similar setup, albeit with only one SunnyBoy and smaller battery capacity. What you want can definitely work - I am basically setup for maximal self consumption, i.e. available solar power will first power loads, then charge batteries. Batteries will supplement solar power if necessary. I revert back to grid once my batteries are down to 30%. My system was configured by the installer. I have looked inside the system settings and am glad I did not have to try and decide what settings to utilise. If you want I can send you the contact details of the engineer that designed the system and then implemented all the settings. He may be willing to help - probably not for free....

Thanks so much! That is very useful information and a very reasonable price. As you say Oranjezicht is just next door to Vredehoek and they will understand the Cape Town wind!

Hi This is my first post in this forum, but I have been following many threads over the last few weeks and have learnt a lot. I am currently still planning my solar setup, but have made good progress. Load reduction -Changed swimming pool pump to a variable speed drive pump that uses approximately a third of energy -Had EVT solar geyser installed (works great!) -Planning to switch lights to LED I am based in Cape Town so will go the whole hog for a formal and correct approval of GTI (Goodwe Hybrid and Pylontech batteries) My question I am based high up in Vredehoek where the South Easter can be extremely strong and vicious. I am planning 12 X 330 W panels on the roof and am of course keen for the panels to stay on the roof and the roof to stay on the house. The suitable roof area is reasonably small so the panels will be fairly tightly packed. I would also like to be able to show my insurance that I have done due diligence. Do you have any recommendations regarding structural engineers that have worked with solar before and could review and comment on planned installation without breaking the bank? Any leads you can give me would be greatly appreciated. Thanks a lot