The inverse relationships between Speed & Range in an electric car

Fossil fuel vehicles (ICE) are much more efficient or economical on a “long trip”. And much more fuel-hungry in stop-go traffic. The reason comes down to acceleration. In stop-go traffic, you have to accelerate much more often than when coasting on a freeway where acceleration is zero. Coupled with this is the fact that in traffic, and after accelerating, you use your brakes to bring you to a stop and lose all that “momentum” gained with no benefit except heat in your brakes.

With an electric car on the other hand, when you slow down, the electric car harvests energy from the deceleration to re-charge the battery, creating more stored energy.

Therefore, we can think of an ICE vehicle as being more fuel-efficient at high speeds and EVs as less fuel-efficient at high speeds. The real problem is with the ICE vehicle’s inability to harvest energy when slowing down.

Cost of fuel in an ICE vehicle vs cost of electricity in an electric car

95 octane petrol price has just (5 April 2022) shot up to R21.96 per ltr. This is from R17.23 per ltr last year. Assuming an ICE vehicle does on average 10km to a litre of fuel, it would cost R2.20 to drive 1km. Juxtapose this to the cost of running an electric car. A Jaguar I-Pace has a 90kWh battery (the size of the fuel tank). The cost of electricity at your home is cR2.30 per kWh. It, therefore, costs about R207 to fill a Jaguar I-Pace. You would get roughly 300km on a full charge. It, therefore, costs R0.69 to drive 1km. Assuming both cars do 150,000 every 5 years before replacing, fuel cost would be:

• ICE = R330,000
• EV = R103,500

At a saving of R226,500. Considering a Mini SE costs R630,000 new, you are actually paying R403,500 in real terms.

Cost of installing an electric car home charger

Electric car charging at home is the most cost-effective and convenient way to fuel your EV. Naturally, you can use the 230v 3pin wall socket cable that comes with your electric car. However, you will be limited to about 3.3kWh of charge, the slowest way to charge an EV.

Most electric car owners opt for an AC “fast-charger”. Electric car home chargers come in many shapes, sizes and configurations. Portable electric car chargers, wall mounted electric car chargers, with and without onboard touch screens, however, all do the same thing, charge your electric car at about 7.4kWh to 11kWh (depending on your electric car’s onboard inverter) and sometimes 22kWh in a 3-phase installation.

Prices for these electric car chargers range anywhere from R7,000 to R13,000 depending on your needs.