By Dr. Alain Naef, Assistant Professor of Economics at ESSEC Business School
Tree planting has become one of the most popular and politically convenient tools that businesses use to be climate conscious. However, in our recent study at ESSEC Business School, we set out to test whether reforestation can meaningfully offset carbon emissions generated by the world’s largest fuel companies. And the findings have left serious doubt on one of the most popular environmental strategies adopted by organisations seeking to offset their climate footprint.
Our research analysed the carbon footprints of the 200 largest companies globally, and what we found is that relying on tree planting to offset carbon emissions from fossil fuels is not only unsustainable, but, also, both financially and physically unattainable – and for businesses to fully mitigate their emissions through reforestation, via planting trees, alone, it would require a forest larger than North and Central America, combined.
And, even if there was such a vast expanse of land available – which there isn’t – financially-speaking, it would cost a staggering figure. The lowest projected cost has been calculated to be at least $11 trillion. And with a realistic carbon cost of $150 per ton, none of the 200 analysed companies would remain economically viable.
Via the study, we also explored other offsetting alternatives, such as direct air capture – a process that directly removes carbon dioxide from the atmosphere. However, the method was found to be even more costly, at seven times current global GPD, and again would require large land usage.
Beyond cost and feasibility, planting trees on such a large scale actually poses a serious threat to the agriculture – biodiversity, water resources and food security. Our findings stress that a large number of the world’s unforested areas, which would potentially be reforested, would be unable to support tree growth due to poor soil nutrition and wrong climate conditions. And again, mass reforestation into unsustainable areas could potentially cause more ecological harm than good.
While tree planting appeals to companies in its simplicity, it cannot be a substitute for the structural changes that are required in order to reduce fossil fuel dependency.
Climate policy must evolve. Businesses and governments need to prioritise reducing their fossil fuel emissions rather than relying on planting trees to offset. As the climate crisis worsens, our research serves as a stark reminder that real solutions require immediate and fundamental change, not just weak offsetting schemes that pose a further risk.
