Power needed for electric cars and its CO2 emission

Published: 2018-10-15; Last edited: 2018-11-22

Just some calculations, because I was curious. The Kraffahrtbundesamt says the kilometers traveled by all road vehicles (KFZ) in 2017 was 730 000 000 000 km. In average an electric car needs around 168 Wh/km (summer) and 225 Wh/km (winter) (heise.de)

730000000000 km(168+225) Wh/km/2=143.445 TWh730000000000~\mathrm{km}*(168+225)~\mathrm{Wh/km}/2 = 143.445~\mathrm{TWh}

All power generated in 2017 was 549.9 TWh in Germany (energy-charts.de) with 38.2 % coming from renewable sources. That means all power needed can be produced by renewable energy. So nothing utopian, though also not really an easy task.

Typical for automobile batteries could be a capacity of 50 kWh and a live expectancy of 500 charges.

143445000000 kWh/(500 ch./bat.50 kWh/ch)=5737800 bat(teries)143 445 000 000~\mathrm{kWh}/ (500~\mathrm{ch./bat.}* 50~\mathrm{kWh/ch}) = 5 737 800~\mathrm{bat(teries)}

So 5 737 800 batteries are wasted per year.

That sounds like a lot. Compared to 10 000 000 per year of normal car batteries (12V) (welt.de, german) it is still a lot, especially if you count in the price.

110 kg CO2 per 1kWh are used for producing a battery (Lithium ion, wiki).

must be updated: 525600050 kWh110 kg/kWh=28908000000 kgCO2=28.908 MtCO25 256 000 * 50~\mathrm{kWh} * 110~\mathrm{kg/kWh} = 28 908 000 000~\mathrm{kg_{CO_{2}}} = 28.908~\mathrm{Mt_{CO_{2}}} per year!

909 Mt of CO2 were emitted in Germany in 2016. 166 Mt was produced by the transport sector (I can't find the numbers for road traffic). If you use 135g/km (auto.de, 2013) CO2 as a ballpark figure normal the emission is 98 550 000 000 kg = 98.55 Mt.

489 g / kWh of CO2 are emitted in germany (2017, umweltbundesamt). That means that 0.489 kg / kWh * 131 400 000 000 = 64 254 600 t = 64.25 Mt are emitted for powering the road traffic sector. In sum (battery production and power for moving the cars): 64.25 Mt + 28.908 Mt = 93.16 Mt ! That is roughly same as the emission of conventionally powered road traffic (without counting in the power needed to extract oil, produce gasoline and diesel)!

< to bee continued or at least edited >