Post Climate Change Debate Investigations

This week I had the luck to participate in a debate about climate change at work. For me it was a forum to promote the first of the “three R’s” (reuse) that Jack Johnson introduced to me but there were other ideas, and a lively debate was had! As one would hope, the collateral effect of getting together and exchanging and exploring new ideas is that interesting lines of exploration are raised to help clarify certain ideas. So read more for two doubts I had post debate and my investigations into them!

Investigation 1: is it really possible that Diego’s trip to NY increased his C02 footprint by 2 tons?

In the debate it was presented that to meet the target of the Paris Agreement each person should reduce their C02 to about 2 tons per year by 2030 and that one of our moderators, Diego, had made multiple long distance plane trips this year and just one of them (a trip to NY) had generated 2 tons and we joked that he had used his allowance for the foreseeable future. This got me wondering if this data point was at all possible because to generate 2 tons of C02 a plane would have to be caring LOTS of tons of fuel, because although I am not a chemist, I do remember the law of conservation of mass that states the output cannot exceed the mass of the input.

So how much fuel can a plane really hold?

Well, for this I did multiple searches on google without getting anywhere, so I decided to go to ChatGPT and of course this was cake work for it (or is that him or her? woooohhooo nelly that is a whole other debate!) and I quickly had answers that although I did not have its sources to verify the information, I did perform double checks afterwards with additional google searches and it appears pretty spot on:

  • The MAD-JFK route appears to use a Boeing 787-8
  • Distance: 5,800 km
  • Estimated fuel required: 67,373 liters
  • Weight of jet fuel: 0.8 kg per liter
  • Total fuel weight = 67,373 × 0.8 = 53,898 kg (53.9 metric tons).

So at least we confirm that the plane has LOTS more weight in fuel than I had anticipated. But if the Boeing 787-8 has a capacity of 242 passengers, why would poor Diego be responsible for 2 tons of the 54 tons? That must mean that the trip generated a whole lot more than 54 tons of CO₂??
Let me ask:

Waitaminute now! What about the law of conservation of mass??? Well, my little buddy ChatGPT also educated me on that: when the fuel is burned it is combined with oxygen, so that adds to the final output and burning 1 kg of fuel can generate 3.16 kg of CO₂! So our 53,898 kg of jet fuel would generate approximately 170,299 kg of CO₂. And if we divide that by each of the 220 passengers, each would be responsible for 774 kg of CO₂ or 1.5 tons round trip.

So was wrong on my gut instinct that Diego really generated so much C02 with is NY trip!

Investigation 2: Does forcing me to replace my old VW car really make sense from a CO₂ point of view?

At the end of this year (18 days from when I am writing this) my VW car will no longer be allowed to drive in Madrid because it is a car that has no environmental classification sticker (distintivo ambiental) because it is a diesel car made before 2006.
This means I will have to break the first R (reduce) and buy a new car. But waitaminute! Is is possible that throwing my old car out could possibly generate less C02 if we were to take into consideration the entire lifecycle including all the CO₂ needed just to make a car?

Let’s have another conversation with my little buddy chatGPT!

How much C02 is needed to make a new car?

Ok how much C02 does my poor old VW generate for each km driven?

And now, drum roll, if I drove 7,404 km last year when will I reach the “break even” on CO₂ emissions be reached when replacing my current car with a new one?

Yea. just what I thought. Jack was right: the most important of the the three R’s is reduce, and throwing out perfectly good cars makes no sense.

Update!!!!!

While searching for details about environmental classification sticker (distintivo ambiental) I have found breaking news just published as I write this that I might be able to use my car through 2025!

Thanks for reading and feel free to give feedback or comments via email (andrew@jupiterstation.net).