But it isn’t all that easy
Electricity isn’t as simple as she thought it would be
When we have blackouts during the day, we run more appliances and have the geysers on because the 10 panels generate about 5.4kW of power during sunny daylight hours. With a 5kW inverter, you can have 10kW of batteries, but more than that might tax the inverter too much. We also added the second battery because we’re heading into the rainy season and four-hour blackouts sans maximum power coming from the panels on cloudy days means we’ll need the battery reserves.
Things will go wrong
We installed the entire setup in the spare bedroom so that I can keep an eye on the system and also because the WiFi extender is in the spare bedroom. The inverter needs to be close to the WiFi router or an extender.
The Sunsynk app works well on my iPhone, and I can monitor our usage to see the amount of power being generated by the panels. I can even see how much power individual appliances are using when I put them on, one at a time. (The geyser timer app also works well on my phone – or not, if you ask my mother.)
I change the levels on the batteries often to ensure that they go down to 50% twice a day (when we’re not having power cuts) because this ensures the longevity of lithium batteries. When we’re having rolling blackouts I adjust the charge times to power the batteries up to 100% before the power goes out.
When we installed the additional three solar panels, the inverter suddenly started to feed power back to the grid, which it obviously shouldn’t do.
This problem drove the Crown technician, Marc Taljaard, and me quite mad because this was a completely new system and it should have been functioning perfectly. Taljaard checked and rechecked that every component was properly installed. Then he removed the inverter and took it back to Sunsynk, who were kind enough to check the unit almost immediately because it was brand-new.
Sunsynk didn’t find any fault with the inverter, but when Taljaard reinstalled it, it was still sending power to the grid. Eventually, he decided to change the Current Transformer unit, which turned out to be faulty because as soon as he installed a new one, everything was peachy again.
This experience made me glad that I went with Crown Technologies because things will go wrong with your installation, and when they do you’ll be happy that you took the time to interrogate the installers properly and to choose one that’s committed to getting things right.
Pay as you grow
We didn’t have half a million bucks to spend on our solar power system, so we opted to start small and “pay as you grow”, that is, to add components as we could afford to do so. However, if you don’t need to stick to a budget then you can go with a 30kW system off the bat and you won’t have to give the toaster and electric kettle the boot.
Our initial installation cost was R132,000 and the additional panels and battery have taken that figure up to R181,000. That’s a lot of money, and it’s also why the entire system is covered by our home insurer, Absa.
With all the additional adjustments we’ve made – using LED lights, running major appliances during sunlight hours and installing geyser timers and lower kilowatt elements – we now use just 20kWh of grid power per day. That’s a saving of about 66% (roughly R4,000 per month) and our lights are on during blackouts. While none of this has been easy to achieve, it’s certainly worth it.
The system requires constant monitoring and tweaking, especially during Stage 6 load shedding, to ensure that none of the appliances drain the batteries, which need to be at 100% before the lights go out at night.
I’m still going to talk to the stroppy septuagenarian – ironically named Surya (the Hindu sun god) – about Wim Hof’s cold showers when she eventually calms down, not because this could result in us using even less electricity to heat up the geysers, but because I really do believe that crazy Finn is onto something.