On the journey to renewable solar energy using solar and driving a battery-electric car (EV), I added solar panels to my home along with purchasing my battery electric Jaguar I-Pace EV and replaced by Internal Combustion Engined car. I recently switched to off-grid solar panels and now my home currently runs off of these solar panels. I also have a bank of Lithium-ion batteries to complement the use of renewable energy at night.
The future of electric mobility in South Africa spins on answering many locally nuanced questions. One of the most common questions I get asked about the combination of my battery-electric car and renewable energy using solar panels is:
How much energy does your EV pull from the solar panels?
My battery-electric Jaguar I-Pace draws about 7.7 kilowatts per hour from my home while charging from the solar panels.
How many hours does it take to fully charge an EV using solar panels?
If my battery-electric car is completely dead, it will take roughly 12 hours to charge. However, one doesn’t drive a battery-electric car like you drive an internal combustion engine car. That is until the battery-electric car is completely flat.
The misconception about fossil fuels vs stored renewable energy in a battery-electric car is that you have 90 kilowatts which give you about 350 kilometers range and like with Internal Combustion Engines using fossil fuels, you drive the battery-electric car until the light comes on.
Merely follow the ABCs of owning an EV – Always Be Charging and electric car. Every time I get home, I put my car on charge. And in sunny South Africa, this is even easier to do with solar and renewable energy storage.
If you are always charging, you won’t be charging your battery-electric car for 12 hours at a time. I charge for about two or three hours a day until your battery-electric car is charged to 100% again.
The impact of renewable energy on the battery-electric car using solar panels
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.
In changing your mindset as a battery-electric (EV) driver, unlike with fossil fuels in internal combustion engines, you have to manage your energy storage in your EV so that sunny the South Africa sunlight gives you the best energy availability.
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. In our new world of hybrid working conditions (work from home coupled with work from the office), this is entirely possible.
Do the Lithium-ion batteries in electric vehicles (EVs) lose charge?
Any lithium battery in an electric vehicle loses charge just like your phone will if you don’t use it. Even if you don’t drive and leave the battery off charge, the battery will still drain power.
The role of the 12v lead-acid battery in a battery-electric car (EV)?
Most people don’t know that battery-electric cars have a traditional 12-volt lead-acid battery, just like your internal combustion engines using fossil fuels. The lead-acid battery powers the dash, electronics, and safety systems. Unlike Lithium-ion batteries, lead-acid batteries don’t require sophisticated software to manage them. And therefore they are more reliable to power the crucial features in the battery-electric car.
The computer box in the EV doesn’t get powered by the main Lithium-ion battery.
As mentioned, the battery-electric cars computer box is powered by a 12-volt antiquated lead-acid battery. The actual electric motors of the EV are powered by the lithium-ion battery. Which like any other battery will gradually degrade over time and will lose some charge.
Solar panel inverters and their connection to the Lithium-ion batteries 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.
