Nowadays, the energy transition is said to be a core concern.  According to the thinking mainstream, all our energy needs should be electrified.

While this very hard statement is understandable, taking into account that electricity could be made 100% renewable, the practical use and production of energy require a deeper insight.

Let us have a look on 3 major topics: individual mobility, dwelling heating and electricity production.  Each will be handled in a dedicated article, this one treating of individual mobility.

Individual mobility is strongly related to car transportation.  Of course, electric cars do really have an energy consumption that us of 15-20 kWh/100km where a very recent thermic car consumes rather 5-7 l/100km (which is equivalent to 50-70 kWh/100km), thus a factor of 3,5 in comparison of the electric car.

But the autonomy is often reported as problematic.  Indeed, there is a competition in providing still more battery capacity to bid longer distance autonomy.  This leads to still heavier cars (that become twice as heavy as former thermic cars), which in turns generates a lot of ‘collateral’ problems a.o. accelerated road degradation (and thus maintenance costs), floor resistance of parkings and perhaps later of bridges, without forgetting the increase of energy consumption.

This competition is a non sense when you know that the large majority of the daily driven distances does not exceed 30-60 km, thus requiring less than 5-12kWh.  These figures combined with the fact that a car is only driven during less than 4 hours by day, leaving at least 20 hours for charging the battery, make this capacity competition totally crazy.

With a strategy of charging the car every time it is parked, there is no need for superchargers (which generalization would enormously stress the grid), a power of 3,7 kW (common 16A plug) would be more than enough.

Further, on exceptional days, where the travelling distance could be of more than 200 km till 1.000 km, the battery could be replaced (as you do with your computer mouse), under way (even several times) in less than 1 minute (see Geely battery exchange system: automated replacement in 59”), much faster than any supercharger and without stress on the grid (charging of the depleted battery can be spread along the time, making use of a buffer storage to cover the daily peak demand).

Lighter (electric) cars will also consume less energy and require (very) fewer raw material (e.g. lithium and rare earth quantities), leading to an impressive affordability enhancement.

And further, we could build a travelling booking system (see a previous article: https://edenergy.be/i-way/?lang=en) to avoid each of us to be alone in her/his/its car, glued in traffic jams.  If we only be 2 on board, the amount of cars on the road would be divided by 2, so that there could not remain any traffic jam more and the consumption of energy would also be divided by 2.  By the way, sharing our travels (along this system), can already become a reality with our thermic cars, with the same effects: no traffic jam, halfening of the consumption.

So, if we use electric cars and share our travels, the necessary energy will decrease roughly from around 60 kWh/100km downto around 6 kWh, a division by 10.  While if we use individually heavier cars the decrease could only dive to 25 kWh/100, thus 4 times this figure.

This is very important because the energy needs must be produced.  A factor of 4 on the needs implies a factor of 4 on the production.

Further, today the grid is capable of delivering a defined capacity (to quench the existing needs), but, as of today, the cars are not (or only very few ones) using the grid as energy source, their source is the gasoline station.

In other words, the transition from thermic to electric cars will require the grid to transport the equivalent of 1.500 kWh/year for each (average) electric car.  Applied on 3 million cars they are 4,5 TWh/year.  With a strategy of charging along the 20 hours during which the car is not driven (thus 7.300 hours by year), the additional transport capacity for whole Belgium will be of 620 MW, on a grid capable of 14 GW, thus +4%.  Not negligible, but very limited, even when adding 50% for a lack of uniformity in the consumption bringing the increase up to 6%.

In case of light cars, with shared travels, this comes to 3% and conversely, fat cars individually used, up to 12% and even 60% to 70% (+9 to 10 GW), if they were charged on a concentrated time window of 4 hours by day (e.g. when coming back home).

This means that a wise usage will lead to very small grid adaptations, and thus very low grid investment, except for the widely spread of 3,7 kW charging poles (which lays at least an order of magnitude lower than a 60% grid capability reinforcement).  Conversely, the heavy individually used concentratedly charged cars will require huge investments and thus also a huge increase of the grid cost (for every grid user).

Claiming that moving (shifting) the peak for 2 to 4 hours will solve the problem, is nothing else than lying.  Indeed, dividing 10 GW by 2 or 3 remains a very high figure.

Curtailing the demand will thus not be an affordable solution, while installing widespread 3,7 kW charging poles will be much more economical, enabling to spread the charging along the whole day but also empowering the consumption of excess of renewable production when present while slowing down the offtake in case of scarcity, along each day.

Cars with battery pack not exceeding 40 kWh (possibly split in 2 units of 20 kWh each), combined with widespread 3,7 kW charging poles and completed by distributed battery exchanged stations (as described above) will make the system (cars + charging) very affordable for everyone, at the lowest societal cost.  Conversely implementing a complex flexibility system will only bring a very limited advantage (limited grid investment limitation), in reality a huge increase in the gird costs (roughly at least a multiplication by 2), paid by the whole society for the comfort of a very small group and making the individual transportation unaffordable for the others.