That is excellent question and I would like to know this too.
It’s not entirely clear how many trees you would have to plant, from the data bunq has shared so far.
According to bunq, in order to compensate CO2 for the average European person (which is responsible for about 7 tons of CO2 every year, that number is correct as you can find on Wikipedia) you either have to plant
A. 10 trees a month for two years totalling 240 trees (source: https://www.bunq.com/blog/how-bunq-green-card-plants-trees)
Or B. 10 trees a month for five years totalling 720 trees (source: https://www.bunq.com/assets/elements/designElements/Comment-est-ce-que-la-bunq-Green-Card-plante-des-arbres.pdf)
or C. 24 trees a month for two years totalling 576 trees (source: https://together.bunq.com/d/26986-the-math-behind-bunq-supergreen).
The sources also explain that a tree will take 308 kg of CO2 out of the atmosphere in its 25 year lifetime, or 12,3 kg per year.
Aside from all calculations laying very far apart from each other, there are two things is one big thing to question here:
It appears in bunq’s calculation, the captured CO2 of the trees “in their 25-year lifetime” is measured against the CO2 consumption of an EU citizen per year.
That’s a big difference, meaning it will take 25 years for that CO2 of one year to be compensated, so for the biggest part of the time until 2045 most of that 7 tons of CO2 will still be in the earths atmosphere. Secondly, if you have to plant trees for 2-5 years to compensate just one year of CO2, how will you compensate for those other years. That 7-28 tons of CO2 left unaccounted for.
- To plant 10 or 24 trees each month, you would have to spend 1.000 to 2.400 euros using card payments alone to reach that number. How realistic is that?
Keep in mind, the money you spend on rent, mortgage and health insurance don’t count. For Dutch people, iDEAL payments don’t count either, which has the largest market share on online payments in the NL.
And how are people spending that much money on card payments alone to be seen as average EU citizens? Most EU citizens don’t make enough to spend 1.000 euros on card payments or don’t even make 2.400 euros at all. These big spending bunq users are likely to have a much larger CO2 footprint than the average EU citizen.
I’ve asked about this in two topics before, one of which has been deleted. It would be really great if bunq could be just a little bit more transparent about how the numbers are supposed to add up, in order to feel the claim of “becoming CO2 free in two years” is correct.
Edit 9/6: some corrections after the calculations on CO2 absorption by trees were cleared up in comments below.