Over the last 11 years, our solar has done what we wanted, or should I say, it did what we intended it to do. Load shedding at the time was crippling our effective business work time, and we needed power when our national provider Eskom did not provide. Like a lot of other South Africans.
If you want, take a trip down memory lane and read the few articles we posted about the installation – we really did the installation on a shoe string budget with help of friends.
To summarise, we installed the following between July and October 2015:
- RCT Axpert 5KVa 48V Hybrid Inverter
- 8 x 100Ah 12V Deep Cycle Lead Acid batteries (Royal DC31)
- 9 x 255W Solar Panels from ArtSolar in Pinetown Durban
- Cost was R53000.
Things went well for 3 or so years, and then our inverter started tripping every time Eskom came back online. It turns out we could send it for repairs or replace it. With a lot of luck and kindness from friends at ITWorks, we bought their loan unit for a very reasonable price, and sold our one that could not behave on Eskom to somebody who did not want to connect it to the grid for R3000. But the great thing was we were back to normal. The inverter was the same model and brand, just green instead of grey 😉
Our batteries came to the end of their life after 5 years, and at the time the most economical solution was to replace them with another set of Royal DC31s. That cost was R1350 per battery, total cost of R10800.
A year later we had a lightening strike (even though we have earth spikes on the panels) and one of the solar cable connectors exploded. The repair was done by my friend at iGagasi Cabling, the cost was only the connector at about R50.
Nothing exciting for a while until our second set of DC31 lead acid batteries came to an end – but this time after 3 years – people told me it was because of increased load shedding and the batteries worked extra hard – don’t know how you would measure it after the horse had already bolted, but I made the choice not to go for lead acid again.
We replaced the batteries this time with 2 x Hubble AM5 (5kWh lithium-ion) – the price then was R39000 per battery, costing us R78 000 for the two batteries. Obviously it must have been a time when they were in short supply and in high demand, because the same unit now is around R16000 each.
This battery setup with the RCT Axpert is not a match made in heaven, as the inverter does not communicate properly with the batteries, so the real charge and discharge of the batteries is not always accurate on the inverter, but it has worked with custom settings advised by the technical team at Hubble and has served us well!
Where we are now!
We are ready now to take the next step, but alas….our system is so old that we cannot just upgrade one aspect of it, everything other than the batteries need to go. Let me try to explain it a little better and break it down.
Currently we don’t have the flatlet on the solar system, nor the 4 aircon units and also not the 200l geyser for the house. The inverter would not cope with the draw, and our solar panels don’t supply enough power.
What sparked the idea of upgrading is that our 200l Kwikot has started leaking – very slightly – so we have to replace it. We got quotes for alternative water heating, every single consultant that quoted, gave us a different alternative solution. We looked at gas, heat pumps and solar heated water and also solar powered geysers/elements etc. The prices were a lot more than I expected, it seems contractors have learnt how to charge PROPERLY for their time.
After weighing up the pros and cons, we decided that we would upgrade our solar electricity system enough so that we could include our geyser and hopefully the flatlet on the improved solar system.
The solar panels are 255w, and installing bigger 600w, when you connect the two different panels, they drop to the lowest denominator – so for that reason, we replace the entire bank.
The inverter cannot take the bigger load draw from the house with the geyser, also cannot handle more panels (or should I say cannot handle the amount we want to put on the roof) and it does not talk properly to the batteries, and therefore does not manage the battery bank correctly.
The batteries can be upgraded, whether we change the rest or not, we just need to stick to the same size. I don’t want to sell them and get a new bigger battery – maybe it is because I cannot swallow how much the value of the batteries has dropped 😉
Our current electricity only bill is between R1500 and R1600 per month.
Our plan going forward
Replace the geyser – happening as I type, just not that fast as I am doing as much of the simple labour before calling the plumber to do the plumbing. I am laying cables and conduiting – ready for the electrician to connect – I am fitting the geyser to the wall outside and locating incoming water pipes ready for the plumber.
Install a new 12kVA hybrid inverter – yet to be decided on brand and whether 12kVA will be enough.
Install another 2 Hubble batteries – same size as the current two, as far as I know it is better to use the same size and brand when increasing the battery bank.
Replace the 9 solar panels on the roof with either 9 or 12 x 600W panels on the roof.
While the above is happening, I am going to improve the cabling, DBs, conduiting etc, as since we installed 11 years ago, there have been advancements in hardware and new ideas that make more sense going forward. Like reducing the circuits to the garage DB and rather increase the circuits that are related to the house to the main house DB. Basically, the DB in the garage, handles the DB for the garage and the solar inverter feed back to the main house DB and all the house circuits run from the house DB. Should have done it like that in the beginning, but then we only had a handful of circuits on the solar – so it made sense to run them from the garage DB.
Anyway, our upgrade begins, and we will keep you posted as we go, so that you too can do a similar upgrade, or just to provide a little humour on our bumpy journey.
