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Charging infrastructure required to get to 100% electric transport in the Netherlands

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The question
How much infrastructure do we need when ALL 8 million vehicles (and buses and trucks!) in the Netherlands go electric?

The answer will surprise you: we could get to 100% electric transportation in the Netherlands, just by converting the 4000 existing gast stations to fast charging stations which have an average of 14 fast chargers.

Keep reading to find out how I came to this conclusion!

Situation today
Every year, around 12 billion liters of mostly diesel and gasoline (LPG is tiny) is burnt to power all terrestrial transportation in the Netherlands. These 12 billion liters are dispensed through a little over 4000 gas stations in the Netherlands. So an average gas station dispenses 3 million liters of gasoline per station, per year. That’s over 8000 liters per day.

Let’s assume that – on average – a vehicle with an internal combustion engine uses 1 liter of diesel/gasoline to drive 15 kilometers. (This assumption is optimistic because most cars don’t get this mileage and buses and trucks certainly don’t. But let’s be generous to the fossil fuel camp.) So an average gasoline station enables 45 million kilometers driven per year. That’s about 123.000 km per day!

How much is the equivalent in electricity?
To keep things simple, I’ll now try to find out how much electricity per station is needed to enable these 123.000 km per day. Is it an outrageous amount or is it doable?

Let’s assume that on average an electric vehicle uses 1 kWh to drive 5 kilometers. (Teslas – the heaviest electric cars on the road – regularly report this efficiency. There are reasons to believe EVs will become more efficient than this, but we also have to include trucks and buses, so this will cancel out my pessimistic assumption. So I think I’m not overly generous to the EV camp here.) To enable the same number of kilometers as the average gas station, a fast charging stations should be able to deliver 9 million kWh (45 million km / 5) per year. That’s 25.000 kWh per station per day!

Now we have a number. Can we get to this number?

If we can crank up the output of a fast charging station to roughly 25.000 kWh per day – we could charge ALL road vehicles in the Netherlands by simply converting these 4000 gasoline stations to fast charging stations. If the answer is no, we’ll need more fast charging stations.

Remember two things:

Can we get to 25.000 kWh per station per day?
An important factor is charging speed, which needs to go up in the coming years in order to get to our goal of 25.000 kWh per day. Most large car manufacturers have joined the CHARIN association – which promotes the “CCS” fast charging standard. This standard allows fast charging speeds of up to 350 kW (1000 Volt * 350 Ampere). That is 7 times as fast as the current 50 kW CCS and Chademo fast charging standard.

Let’s assume that in practice, the top speed will not be 350 kW but 300 kW. So a single charger can dispense 300 kW on maximum power. Every hour this thing runs at full capacity, it’ll dispense 300kW * 1 hr = 300 kWh. In 24 hours, this adds up to 7.200 kWh.

These fast chargers won’t be charging at 300 kW all the time. There will be older cars charging, some batteries may taper the charging speed in hot or cold conditions, and when its state of charge approaches 90%. So, on average, let’s assume the charging will take place at 50% of the maximum speed – 150 kW. This reduces the output of the single fast charger to 3.600 kWh per day.

Fast charging stations won’t be fully occupied 24 hours per day. There will be downtime for lots of different reasons – no cars are charging due to holidays, scheduled maintenance, grid downtime, switch time between cars, etc. So let’s assume that the “capacity factor” of a station is just 50%. It will be running at half speed, on average (so sometimes it will hit 10% and other moments 90% capacity). That’s 1.800 kWh per charger per day.

To deliver the 25.000 kWh per station per day that we need, we therefore need to divide 25.000 kWh by 1.800 kWh (the real world output of a single fast charger over the course of 24 hours) to get to the number of fast chargers we need per station: 25.000 / 1.800 = ~ 14 fast chargers per station. Is this possible? Yes it is! 14 fast chargers per station is not that much. Tesla routinely builds such stations with over 12 fast chargers all over the world.

This means we could get to 100% electric transportation in the Netherlands, just by converting the 4000 existing gast stations to fast charging stations which have an average of just 14 fast chargers.

And remember, this is a 100% fast charging scenario. Less stations or chargers per stations are needed when fast charging is a lower percentage of the charging mix. See the Annex I below for a couple of other station setups.

Can these stations reach high capacity factors, i.e. be charging most time of the day? I think so too. With an increasing percentage of self driving cars in the 2020s, EVs can gradually learn to drive themselves to fast charging stations. Charging at night will be no problem at all with self driving cars. Self driving cars are perfectly suited to fully utilize the power of fast charging stations.

Grid connections
Another way to look at the infrastructure challenge for electric vehicles is the grid connections required to deliver this electricity to the vehicles. When a station dispenses 25.000 kWh per day, this translates into a continuous load of  little over 1000 kW (24 hrs * 1000 kW = ~24.000 kWh). These 1000 kW (1MW) grid connections are proven technology.

If we could could connect all of these 4000 fast charging stations with a  ~1MW grid connections to the medium voltage grid, there would be far less need for costly upgrades of the low voltage grid which runs through neighbourhoods.

Battery buffers
At peak hours (when all chargers are occupied and charging at full speed) the load per station could be up to 4.2 MW (because the *peak* output capacity of the station is 14 fast chargers * 300 kW). Meeting this peak demand is possible through the installation of on site battery buffers which charge during low demand hours and discharge during peak demand hours. These battery buffers are also proven technology.

The answer is clear: if we can ramp up the maximum charging speed for electric vehicles to 300 kW, there are no physical or economic barriers to the cost effective introduction of infrastructure that supports 100% electric transport in the Netherlands.

 

ANNEX I: station capacity

Station 1.0 Station 2.0 Station 2.1 Station 3.0
Charger speed_max 50 kW 150 kW 150 kW 300 kW
Number of chargers per station 2 4 8 16
Utilisation of chargers 50% 50% 50% 50%
Average charge speed 70% 50% 50% 50%
Grid connection required (with battery buffer) 150kW 300 kW ~1.200 kW
Capacity per day (kWh) 840 3.600 7.200 28.800
Capacity per year (kWh) 306.600 1.314.000 2.628.000 10.512.000
Gasoline/diesel equivalent p/year (liters) 102.200 438.000 876.000 3.504.000
# of gasoline stations ~4000 ~4000 ~4000 ~4000
# of stations to transition to 100% electric transport (assuming 100% fast charging scenario) too many too many ~13.700 ~3400
# of stations to transition to 100% electric transport (assuming 50% fast charging scenario) too many ~13.700 ~6.850 ~1.700 (!!)
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