Electric vehicles (EVs) are becoming increasingly popular as consumers seek more environmentally friendly (and cheaper to run) transportation alternatives to their petrol and diesel counterparts. We’ll have all heard the main concern (aside from price) of making the personal switch to an EV, is range anxiety. Two ways to tackle that today: (i) make the battery bigger so you can go further on a single charge and (ii) reduce charge times to such an extent that a few minutes at a charging point is no longer seen as an inconvenience. Assuming option (i) is out of scope due to the resultant increase in vehicle cost (the battery pack is 40-60% of the cost of the vehicle), let’s focus on option (ii). While there have been claims of technologies that enable ultra-fast charging times, the reality is likely to be that you won't be charging your electric vehicle in under two minutes anytime soon, and here’s why…

It comes down to basic maths. If the average EV battery capacity is around 60 kWh and you wished to charge a battery of this size in two minutes, you would need to supply it with an incredible amount of power - over 1.8 megawatts (MW) to be exact. For comparison, the average household in the UK uses around 300 W (Watts) of power at any given moment. That means that charging an EV battery in two minutes would require the same amount of power as 6,000 homes. To put that further into context, at the time of writing, the UK is generating 30 GW (gigawatts) of electrical power. If all that power was used to charge EV batteries alone, only approx. 16,500 vehicles could be charged at any one time. Compare that to the 33 million cars there are on the road in the UK today – that’s only 0.05% of all vehicles. Clearly completely impractical even when you consider nuances like the actual need to charge in two minutes, time of day, initial state of charge, etc.

The simple fact is that whilst we strive for technologies which allow for ultra-fast charging, we can’t get around the basic physics that to move a vehicle through the air from point A to point B requires a lot of energy – energy that needs to be delivered and squeezed into a battery. So, what’s the key then? Reduce the amount of energy needed to be stored in the battery (so you can fully charge it more quickly) by reducing the weight of the vehicle (assuming you want to travel the same distance) and improving how easily the vehicle cuts through the air (it’s aerodynamic characteristics). How can this be achieved? Use lightweight composite materials, increase battery energy density, reduce vehicle size (because in the UK, average vehicle occupancy is only 1.7 passengers per car), reduce frontal area and resulting drag coefficient, employ active aerodynamic elements – but don’t forget about those unintended consequences I wrote about in my last blog (Addressing the unintended consequences of decarbonisation ). Technologies and innovations that address these areas are where I’ll be placing my bets.