Yes, carbon neutrality is more ambitious than Factor 4!

The news caused quite a stir: On Thursday, February 7, the newspaper Libération reported that France had “abandoned” its Factor 4 target, which aims to reduce France’s greenhouse gas emissions by a factor of four by 2050 compared to 1990 levels. This goal, established in the 2000s, is one of the major objectives of France’s climate policy; incidentally, it is what inspired the name of the consulting firm writing this article.

Libération pulls no punches in its criticism: replacing Factor 4 with a carbon-neutrality goal would amount to a “surrender,” a “step backward,” or even a gift to the fossil fuel industry. What’s the real story? To begin with, a definition : France will achieve carbon neutrality when the amount of greenhouse gases emitted each year within French territory is equal to the amount of CO2 absorbed by the country’s “carbon sinks”. These sinks can be either natural (forest growth, carbon storage in soils, etc.) or technological (carbon capture and sequestration at industrial sites or through diffuse capture by removing carbon from the air, etc.). To put this in perspective, total emissions in France currently stand at around 450 MtCO2/year, while the country’s net carbon sink is approximately 40 MtCO2/year. Carbon neutrality therefore remains a very, very distant goal. One thing is certain: A “carbon neutrality” goal is not the same as an emissions reduction goal. Factor 4 leaves no room for ambiguity: the goal is to reduce emissions by 75% compared to 1990—period. "Carbon neutrality," on the other hand, opens the door to addressing not one, but two factors: emissions and carbon sinks. It is therefore understandable that this dual freedom might inspire mistrust: in theory, why not simply increase the carbon sinks to match current emissions, which would allow the entire economy to continue emitting greenhouse gases with impunity?

GHG emission levels and carbon sinks targeted by the SNBC. Carbon neutrality is achieved by reducing emissions to one-sixth of 1990 levels, reaching an emission level of 85 MtCO2/year. Natural and technological carbon sinks, totaling -85 MtCO2/year, can hardly be mobilized any further.

The reality is that it is extremely difficult to adjust the second parameter—that of carbon sinks—. A proactive national policy—one that is difficult to implement—  covering forest management, the use of wood products, and the prevention of land conversion will barely be enough to double France’s natural carbon sinks compared to 1990 (from -35 MtCO2/year to -70 MtCO2/year). As for sinks resulting from emerging negative-emission technologies (carbon capture and sequestration), the costs are so prohibitive, the geological storage potential on French territory is so limited, and public acceptance is so low, that the National Low-Carbon Strategy projects a development of barely 15 MtCO₂ by 2050—equivalent to just over 20% of natural carbon sinks. To date, it has not been possible to identify geological sites in metropolitan France capable of accommodating comparable levels of carbon.

Carbon neutrality means reducing emissions by a factor of 6 or 7, not just by a factor of 4

Thus, given these ambitious levels of well development, it would be necessary to reduce emissions by a factor of 6 or 7 in the new National Low-Carbon Strategy, rather than by a factor of 4, as historically targeted by Factor 4. It is important to note that that carbon sinks will likely not be able to serve as a "wild card" to avoid meeting the crucial emissions reduction target. On the contrary, their development is difficult and subject to immutable physical limits (a forest cannot grow indefinitely, and carbon cannot be stored indefinitely beneath our feet); and furthermore, carbon sequestration is not a permanent solution, as forests remain vulnerable to climatic hazards (fires, storms). These sinks are less of a convenient adjustment variable than a genuine exogenous factor—one that is difficult to manipulate—which sets the maximum possible level of emissions in 2050. Perhaps the most sensible approach would be to enshrine in law both the goal of carbon neutrality AND a sub-goal of a minimum reduction in emissions. After all, we cannot rule out the possibility of a miraculous technological breakthrough that could increase the capacity of carbon sinks tenfold.

A problem for the rich? Yes! Nevertheless, it remains crucial to ensure that reducing emissions remains a priority, that is, the renovation of our buildings, the decarbonization of the transportation sector, the transformation of our heavy industries, and the reduction of emissions from the agricultural sector. In short, we must ensure that France’s long-term climate strategy serves as a catalyst for a profound transformation of our economies—and not merely a race toward a “miracle” negative-emissions technology. To stop the water level in a bathtub from rising, it’s better to turn off the faucet than to increase the size of the drain. Perhaps the most concerning issue isn’t this carbon neutrality goal, but rather the revision of the overall cap for France’s second carbon budget for the 2019–2023 period, which has risen from 398 MtCO₂ to 421 MtCO₂ due to accumulated delays in the transportation and building sectors. This is, unfortunately, concrete and immediate proof that France’s long-term ambitions are not yet being put into practice in a sufficiently ambitious manner. A legal expert quoted in the Libération article points out that the danger lies in the lack of a clear definition of the concept of carbon neutrality. And that is absolutely true. That is why Carbone 4, in consultation with a high-level scientific advisory board and several major French companies, has been working since June 2018 to provide a clear definition of how this concept of “neutrality” applies to businesses. This is to avoid opening the door to ambiguity—and thus to inaction. Undervaluing the meaning of words and concepts is a critical danger at a time when raising our ambitions is a matter of survival.