Plugging into sunshine: Can your home solar setup power your EV in South Africa?
With load shedding casting a long shadow over Mzansi and the government pondering green car incentives, many South Africans are asking: Can my rooftop solar panels juice up my EV? While the solar-powered EV dream sounds idyllic, the reality is a bit more complex.
Related: Can I take my EV offroad?
The sunny reality check
The truth is, your average home solar setup isn't quite a powerhouse for your EV. Most household systems simply don't generate enough power to fill an EV battery's thirsty soul. The average new EV battery packs a punch of 30–60 kWh, with some luxury models sporting over 100 kWh. That's a whole lot of sunshine to convert.
Related: Are their charging stations for EVs and plug-in hybrids in SA?
Adding some batteries to your setup makes a hybrid-charging system possible
So, can you power your EV with home solar alone in South Africa? The answer, for now, is no, but if you add a bank of lithium-ion batteries to complement the solar panels, then it's a completely different story.
George Mienie, our CEO, owns a fully electric Jaguar I-Pace (with a 90 kWh battery) and uses a combination of sunlight and stored energy from lithium-ion batteries to power his EV. Here's how he manages to do it:
I plug my battery-electric car in at 7:30 am in the morning. I let it charge for about two to three hours. It is then fully charged before 12 o’clock that morning.
Solar energy allows my EV to be charged during the day using sunlight. When there is not enough sunlight the solar inverters switch to Lithium-ion battery stored energy. Effectively, the sunlight on the solar panels in my case generates more solar energy than the car or my home requires. Excess solar energy is then stored in Lithium-ion batteries. Solar inverters are set up to prioritize the energy drawn from the solar panels first and then from Lithium-ion batteries. And only then, if neither have enough solar or stored energy, to then pull electricity from the grid (Eskom) in South Africa.
The solar inverters at 12 kilowatts take two to three hours at most to charge the stored energy Lithium-ion batteries from the solar panels from zero to 100%. However, these Lithium-ion batteries are also not designed to discharge down to zero, just like a battery-electric car, so I’ve set it to go down to just 50%. This also reserves power during the infamous “load shedding” in South Africa! This means there to be 50% stored energy at all times. - George Mienie, AutoTrader CEO.
Read the full story on the George Mienie website here.
Verdict
If you have solar panels, a fully electric vehicle will require some additional help. A plug-in hybrid with a significantly smaller battery is a better bet, especially if you have a home vehicle charger installed, but having a battery reserve will also make things a lot quicker and easier. Read more about this here.
Read our Volvo C40 Recharge launch report here
Watch George Mienie's YouTube video here, namely: How solar renewable energy can complement battery-electric cars
