Why home charging is more convenient & cheaper?
One big reason some are against electric vehicles is that charging is slow…
This is against their measure of filling their tank in a couple of minutes with petrol or diesel.
When using the fastest DC charger at a charging station, an electric car typically takes at least 30 minutes to get 80 percent charged.
In the future, though, far faster charging might be possible.
Companies are developing new lithium-ion battery materials, as well as new “solid state” batteries, which could recharge in sub 20 minutes.
However, there are still many science and engineering challenges before ultra-fast-charging EV batteries are technically feasible and affordable.
Some experts even question whether electric vehicles that can be charged so quickly, are really the future we want, especially with the demand that will be required on the national grid.
Because of problems with fast charging, all EV batteries have built-in charging speed limits, set by the car’s on-board charge ports.
A 350Kw fast charging station might, in theory, be able to charge an Audi E-tron’s 95Kwh battery in about 15 minutes. But the battery itself can only accept about 150 Kw of power, giving an actual charging speed closer to 40 minutes.
Exactly how fast a battery will recharge depends not only on the charger or how many Kw of power the battery was designed to accept, but the battery’s size, how charged it is, and even the weather.
Although, the latest fast charging stations can often get an EV battery 80 percent full, potentially adding hundreds of miles of range, in about 30 minutes.
While adding 200 miles of range in 30 minutes is fast, it’s still no-where near the less than 5 minutes when refuelling a petrol or diesel vehicle.
New research may be pushing super batteries capable of ultra-fast charging speeds closer to reality.
But, even if EV batteries that can charge in less than 10 minutes are technically possible, it’s not clear that ultra-fast charging will ever be practical or affordable.
At 400 volts, today’s super-fast charging stations already draw much more power from the grid than the volts EV owners use to charge their cars at home, whilst being much more expensive too.
So, maybe there’s a balance to be struck at the social level and the charger level, to find the right combination of convenience and cost.
If all of society is to change to electric vehicles, there is a need for ultra-fast charging stations, which will allow people to carry out their work and recreation in a not too dissimilar fashion to today.
But once we’re all driving EVs, and if everyone expected ever-faster charging to be available all the time, this would surely break the grid and cause pockets or even mass blackouts.
So, charging overnight at home, when demand is lower will help to balance out the strain on the grid, whilst being much more affordable than paying high prices for ultra-fast charging.
…let’s face it, it’s more convenient & cheaper charging a car whilst sleeping.