How much electricity do we need to electrify all our vehicles?

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

31 August 2025

I recently saw a 14-seat electric passenger van [matatu]. It is a reminder of the slow but steady growth of electric vehicles (EVs) in the world. Still, several concerns have been raised by EV detractors, the main ones being the how far they can go without recharging and how long the need to fully re-charge.

Range anxiety (as it has come to known) is unjustified. Most motorists drive less than 100km daily while most modern EVs can travel 500km on a full charge. This is comparable to the 500km - 600km we get from a full tank of fuel in a conventional vehicle.

However, while it takes about 10 minutes to fill up a tank of petrol, re-charging an EV can take several hours. But when you think about it: how times do motorist go to a petrol station and fill up the tank? Very rarely. Drivers normally put just enough to get them to where they are going. The same is doable in an EV – you don’t have charge fully.

In any case, a 500km journey takes a whole day. So, there will be enough time to recharge the EV when one gets to their destination!

There is also the question of electricity supply. While charging points are easy to put up (most EVs come with a home plug-in unit), the issue is whether there is enough electricity to meet demand from EVs. In Kenya, we consume about 4.5 billion litres of fuel annually. Each litre has about 32 mega joules (MJ) of energy. So, the 4.5B litres have 144B MJ.

Now, fuel powered engines are very inefficient. They utilize only about 30 percent of the energy in moving the vehicle. The rest goes to waste – mainly as heat. I am always amazed that the world accepts this wastefulness as normal!

This means that all our motor vehicles put together consume about 43.2B MJ of energy – 30pc of 144B MJ. If we changed all of them to EVs, this energy would have to come from electricity. Electric motors are a lot more efficient: they waste just 10pc. Thus, the EVs would need about 48B MJ from electricity.

Now; electricity is sold in kWh and one kWh is equal to 3.6MJ. Therefore, if all our vehicles were EVs, they would consume about 13 billion kWh. Interestingly, this is approximately the same amount of electricity we currently consume annually.

Therefore, to go fully EV would require us to double our electricity supply. Looking at the rate of growth of EVs, I think we shall be able to keep up with the extra demand. But we shouldn’t be complacent.