Why retrofit, not build from scratch?
“There are many vehicles on the road that are completely roadworthy, and all you need to do is swap out the propulsion — the diesel engine or the petrol engine and the fuel and tank and gearbox — with an electric motor and regenerative braking, add a big battery and a battery management system,” Booysen said.
“And as soon as you’ve done that, you’ve got an electric vehicle that’s cheaper to run – and more energy efficient.”
Lacock explained that retrofitting is actually a lot cheaper than building an EV from scratch, because you only need to buy the electric motor, inverter and batteries – and it’s definitely cheaper than buying a brand new EV – because an EV would have to be imported.
“If a company retrofits an old vehicle, instead of writing that vehicle off and losing all that money, they’d save at least R500,000–R600,000 than if you bought a new one,” said Lacock.
Stellenbosch University is also doing a retrofit project with Golden Arrow Bus Services, which has 1,100 diesel buses that could be retrofitted.
Lacock said Golden Arrow needs to buy new buses every year to keep the fleet up to date, and is losing money by writing the old ones off.
Based on the Golden Arrow EV pilot programme, they calculated that they would save around R657,000 per bus per year if it was electric – saving on operational costs.
Lacock said retrofitting is the same principle as building a new EV; it’s just using the same frame and chassis, which is good because generally when an ICE reaches its end of life after 10 or 20 years, the frame of a vehicle is still functional.
“So now you can take that taxi and basically give it a second life by electrifying it,” said Pretorius.
And of course, retrofitting over building from scratch has a far smaller carbon footprint, because emissions will not be created in the manufacture of a new frame and chassis, and you’re using a vehicle that would have been dumped somewhere.