My son came from school one day and said: “Dad, wouldn’t it be great if all cars in the world were electric? Then we would have no pollution, Dad! How to explain that to a kid? How to explain that to a person with average or no technical knowledge? How to even explain that to myself? 

As a mechanical engineer and turbine specialist, I worked in the energy production sector. Later I worked in Oil&Gas, and for the past few years, I deal a lot with maintenance in the mining industry. All these industries combined are crucial to answer my kid’s question. 

We need to do basic math first. Let’s start with energy production. We need to calculate how much energy is required to power all cars because this is the amount of electrical energy needed to be produced to substitute fossil fuel. I would take Germany as an example for the basic calculation since it is, by many standards, one of the most developed and technologically advanced countries. Thus, it could potentially implement this transformation. A very conservative calculation is used so that the real numbers could be much more severe. 

Part 1: Basic math

It is assumed that a car’s average power is 100 kW, and the average speed is 50 km/h. For the rest of the data, there are exact numbers available. An average German drives 14,000 km per year, and to do that with a 100kW car on an average speed of 50 km/h, he would need 280 hours and 28.000 kWh of energy. There are 47 million cars registered in Germany, and they would need additional 1.3 trillion kWh per year. German’s total yearly production of electrical power is 0,5 trillion kWh, and that includes all homes and very developed and robust industry. 

Part 2: Energy production

Since fossil fuels cannot be used to produce all that extra energy, it needs to be done with carbon-free energy. The most effective non-carbon energy comes from nuclear power plants. The average nuclear block produces 5 billion kWh/year. To make 1,3 trillion kWh/year, you would need 260 nuclear blocks. Since I am coming from the power generation industry, I will give you one exact data: to build one nuclear power plant you need on average 7,5 years (if you have all the permits) and approximate 15 billion $. 

Let’s try with the wind turbines:

An average wind turbine produces 6 million kWh/year. To have the required extra energy to power all cars in Germany, we would need around 217.000 wind turbines. The assumption is that we have all the time perfect weather conditions with constant optimum wind and no maintenance problems. There are approximately 341.000 wind turbines installed globally, and 2/3 of them would be needed just to power cars in Germany.

Part 3: Mining

Let’s suppose that we somehow manage to produce the required electrical energy. Now we need to distribute it to end customers and produce the batteries. The most advanced new electric cars have potent electric motors and strong batteries. High voltage and high amperage cables are required to charge the cars in an acceptable time (on average 10-20 min for 500-700 km). It is clear from the basic calculation that we need 2,5 times more electrical power than Germany is currently producing. That means that Germany needs a 2,5 times stronger electrical grid. The current grid in Germany is 1,79 million km long. Making that extra cables (without installation and transportation) brings us to around 10 mil metric tons of copper or 3 mil metric tons of aluminum just for Germany, and where is the rest of the world! There is no need to present the calculations for the world’s ore reserves and annual production. Here are the ending results: if we moved all people from Earth to another planet, then put the planet Earth in some refining machine which would extract all copper, aluminum, lithium, and other ore needed for this 100% electric cars project, we would still not have enough ore to satisfy the world’s need.

Answer:

Searching for an answer to my kid’s question, I concluded that we face a difficult challenge on our planet. With current technologies, it is impossible to switch to a non-fossil fuel. We cannot store or transfer the energy to the end customer, even if Merlin the magician creates nuclear power plants and secures constant optimum wind for the wind turbines with his magic wand. I did not even mention other alternative energy sources because production capabilities are so low compared to the needs if we use current technologies. On the other hand, using this amount of fossil fuels is not sustainable because the pollution level is very much in the red zone and close to the point of no return. I would like to hear your thoughts on it.