CO2 – Some rules of thumb
Published on: Dec 21, 2021
CO2 - Some rules of thumb

Dear all,

At the moment the topic of climate protection, Net Zero, energy transition – or whatever you want to call it, is very present in the media.

CO2 is the new smoking.

Until recently, I found the topic totally abstract and hard to grasp. It still is in a way, but I’m slowly getting closer to being able to get a better feeling for it. Sometimes, you just need a comparison or some concrete numbers to be able to evaluate things.

Today, I want to share my – very simple – rules of thumb with you. I don’t claim they are complete or scientifically perfect, but they might be helpful to you.

Question: How big is the problem we want to solve?

Answer: The world’s CO2 emissions are about 50 billion tons per year and rising. We want to reduce these to zero over the next 29 years. That is the short version of the Paris Climate Agreement.

Question: How much CO2 do I emit myself?

Answer: The average person in Germany emits 7.9 metric tons per year. This value includes your personal emissions and a share of general emissions over which you have no direct influence (e.g. public buildings, industry, etc.). Globally, the average is just under 5 tons per year. Qatar has the highest per capita emissions at about 30 tons per year, and a person in Ethiopia emits about 0.15 tons per year. China emits the most as a country, about 30% of global CO2 emissions come from there (but only recently, historically the greatest responsibility lies in Europe and the USA).

Question: How much do I emit by driving a car?

Answer: A Volkswagen Golf has a CO2 emission of about 140 g/km (yes, I know: depending on engine, driving style, distance etc.). So at 12,000 km per year, that’s 1.7 tons. With your Porsche Cayenne Superturboplus you are well above that, if you drive a Kia Picanto you are below that.

Question: Are electric cars better in terms of CO2?

Answer: A medium sized electric car (e.g. Tesla Model 3, VW ID3 etc.) consumes about 16 kWh/100km. The electricity mix in Germany causes about 370 grams of CO2 per kWh. So the emissions are just under 60 g/km, less than half of a gasoline or diesel. If you buy grid electricity in Poland, the value is significantly higher due to the high share of coal-fired power plants, in France (nuclear) or Norway (hydroelectric) it is significantly lower. If you charge from your home PV system, the CO2 emissions are 50-60 g/kWh according to Fraunhofer ISE calculations. Thus, the emissions are below 10 g/km.

Question: How many emissions does flying cause?

Answer: According to ICAO, a flight from Frankfurt to Mallorca and back causes CO2 emissions of 236 kg per person, to New York and back some 700 kg per person in economy class.

Question: What is the cost of all this?

Answer: Currently, the atmosphere is a free landfill. Many have now realized that this is not sustainable and that we are wiping ourselves out through the rise in sea level, the extinction of species, e.g. corals, etc.. The fact that it costs money to rebuild cities like Jakarta, New York or Hamburg in the interior of the country has also been recognized. The German Federal Environmental Agency estimates the environmental costs per ton of CO2 at 180 euros. The current official CO2 price in Germany is 25 euros per ton. The actual trading price has been significantly higher in recent months. Sweden is currently the European frontrunner at around 130 euros per metric ton.

Question: And what does that mean for John Doe and me?

Answer: Do the math:
All inclusive today: 7.9 tons/year * 25 euros/ton = 200 euros per year
All inclusive in the future: 7.9 tons/year * 180 Euro/ton = 1,400 Euro per year
Driving a car with the good old Golf: 1.7 tons/year * 25 Euro/ton = 42.50 Euro/year (included in the 200 Euro)
Vacation flight to Mallorca and back: 0,24 tons * 25 Euro/ton = 6 Euro

Ok, ladies and gentlemen, I have a question for you: What exactly is the problem? It may be interpreted as the arrogance of a rich snob, but I’ll say it anyway: If I can’t afford the extra 6 euros for the flight to Mallorca, I should stay at home. For the money I would get a Sangria there. And then I simply drink something else. Or I drink two beers less. Or I put a towel on the beach once a week instead of renting a deck chair. Then I save twice as much. Same with the car: If my individual mobility becomes 42 euros more expensive per year (that’s three fifty per month) – do I really notice that? I don’t mean as a manager. As an average employee. Three euros fifty cents a month? Yes, I know, there are families who have to calculate very tightly. Yes, we have to find a solution for them. I’m happy to pay seven euros. I don’t care. But why don’t we finally stop demonizing this abstract topic of CO2 taxes?

Or better yet, could it be that the state already collects enough money via the fuel tax and uses some of it – let’s say €3.50 per person per month – for climate protection?

Anyway, what are we actually talking about? I can’t believe that the €200 per year is an unsolvable problem. The supplementary budget for 2021 alone was four times higher at a good 60 billion, and the new debt of the Federal Republic of Germany for 2021 was 15 times higher at 240 billion. Mr. Scholz just made that possible.

Once again, I don’t understand the world. Perhaps you do. Then please let me know.

Have a nice day

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