The amount of carbon that they say could be captured by restoring these trees is 205 GtC, which for $300bn to restore comes to ~70¢/ton of CO2~40¢/ton of CO2. Founders Pledge estimates that, on the margin, Coalition for Rainforest Nations averts a ton of CO2e for 12¢ (range: factor of 6) and the Clean Air Task Force averts a ton of CO2e for 100¢ (range: order of magnitude). So those numbers do check out.
I did not look at the details, but it appears that neither of these estimates take into account opportunity costs. Typical farming profit is around $200 per hectare per year, so if instead you sequester 5 tCO2e per hectare per year, that would cost ~$40 per tCO2e, ~2 orders of magnitude more expensive. By the way, I believe $300 billion divided by 205 billion tons carbon = 750 billion tons CO2 would be $0.40 per ton CO2.
The amount of carbon that they say could be captured by restoring these trees is 205 GtC, which for $300bn to restore comes to
~70¢/ton of CO2~40¢/ton of CO2. Founders Pledge estimates that, on the margin, Coalition for Rainforest Nations averts a ton of CO2e for 12¢ (range: factor of 6) and the Clean Air Task Force averts a ton of CO2e for 100¢ (range: order of magnitude). So those numbers do check out.I did not look at the details, but it appears that neither of these estimates take into account opportunity costs. Typical farming profit is around $200 per hectare per year, so if instead you sequester 5 tCO2e per hectare per year, that would cost ~$40 per tCO2e, ~2 orders of magnitude more expensive. By the way, I believe $300 billion divided by 205 billion tons carbon = 750 billion tons CO2 would be $0.40 per ton CO2.