Comprendre les enjeux de l'agriculture
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The ecological emergency focuses on climate change. This is legitimate, but it leads to a simplifying obsession: energy is scarce, so we must save it. In France, we don’t spare laws and the formula “Energy is our future, let’s save it” is a legal statement that all energy companies must display.

But when we put the question of energy in a broader perspective, we quickly discover the obvious: the energy received by our planet is in excess. What is scarce is space, terrestrial space, and in particular the space needed to exploit this excess energy.

The energy transition brings out this scarcity of space and reinforces it. Agriculture is directly concerned by the energy it consumes intensively and by the energy it can produce (biofuels). But it is also indirectly affected by spatial competition.

Space is scarce, especially for energy and agriculture: it is space that must be saved.

Excess of energy? Because of the sun…

s are of solar origin.  Among them, two families :

energy from a stock, therefore non-renewable (coal, gas, oil)
flow energy, renewable: directly (photovoltaic) or indirectly produced by the sun (hydraulic, wind, biofuels)

The use of coal at the end of the 18th century gave an impression of abundance, and led to an almost explosive growth of material production and demography in England and then in Europe. Fossil energies, because of their ease of use, caused a rupture, the birth of what is called the Anthropocene[2]: the human species became invasive and dyschronic (it imposed its rhythm of evolution on the rest of the living world).

Renewable energies of solar origin, on the other hand, are not rare. On the contrary, they are (theoretically) available in excess. The earth receives in one year, by subtracting what its atmosphere reflects from the solar radiation, 1000 billion gigawatt-hours. This represents more than 10,000 times the energy consumed by humans.

This is the grandiose vision of Georges Bataille (La part maudite, 1949). The systemic vision of the excess. It has been ignored or put aside, wrongly. It leads to the seemingly paradoxical idea that we must not “save” but spend, consume, squander the excess. To avoid growth, deadly over-growth. The greenhouse effect, itself, is a confirmation of Bataille’s vision (a confirmation that he had not envisaged at all): because the greenhouse effect results from two excesses, that of the sun on the one hand and that of the “gaseous proliferation of our industrial activities, of our engines” on the other. I will come back to the question of growth, not to support the simplistic idea of degrowth, but on the urgency of implementing another kind of growth, a new form of development, one that respects the environment, centered on the growth of the sectors of health in the broad sense, of education and training, of research and culture. Reducing the time and drudgery of work but not employment.

There is a third family of energies, those that do not come from the sun.

Deep geothermal energy: 99% of our earth exceeds 1000° Celsius, largely due to natural radioactivity, and it is a practically inexhaustible energy.

The tidal energy which is almost totally linked to the moon.

Finally, atomic energy: in its present form it is not a renewable energy, but the new nuclear technologies (small modular reactors, in particular molten salt and thorium reactors) are getting closer to renewable energies (with better management, and even reuse of some waste), but will not be available for at least a decade. Finally, in the much longer term, we must not forget nuclear energy linked to fusion (producing energy “like the sun”, but on earth).

The deployment of nuclear power could radically change the energy situation, but only after 2050, probably too late to avoid the climate disaster, if nothing is done right away.

The only hope to avoid this disaster lies in renewable energies. Thanks to them, and thanks to nuclear energy from 2050 onwards, we can hope to have a new abundance of clean energy.

A strongly growing energy demand

The totality of the biomass and almost all the energie

This is fortunate because the demand for energy over the next three decades will be very high. First of all, for demographic reasons: there are currently 7.5 billion of us and there will be more than two billion additional people on earth by 2050. Moreover, most of them will live in India and Africa, in countries with immense energy needs; they will have to be fed (under other diets) and we know that agriculture requires a lot of energy, but also to house them, to satisfy basic needs of hygiene and health…

After 2050? The demographic progression slows down, stops and then reverses. Then, nuclear energy takes over and clean renewable energies are mature. However, the methane problem remains, but agriculture will probably be able to meet this challenge. But this does not solve everything, and we still have to get there.

The next thirty years are therefore crucial.

We must reduce the use of fossil fuels as much as possible and as quickly as possible, for many obvious reasons, but mainly to reduce GHG emissions.

Hence the idea of saving energy mentioned in the introduction. These savings are necessary but insufficient. Those realized in the developed countries (G7) give a good conscience but will have a weak impact on climate change, some (for example, the insulation of old buildings and housing) are even false good ideas. The only really interesting savings are the innovations that can be transferred or exported worldwide.

It is in this perspective of economy that the notion of carbon footprint appeared. The European Union is aiming for carbon neutrality by 2050. It will undoubtedly achieve it but, given its demographic weight, this will not change the global situation. The tools of green finance and CSR standards (given the urgency of the situation, it would probably be a good idea to put the environment before social issues) will play a useful role. But it is first and foremost the implementation, at an adequate level, of a carbon tax, if possible at the global level, that can play a decisive role (see the work of Jean Tirole, Nobel Prize in Economics, on the market for pollution rights).

These financial and fiscal tools are at the service of the main strategy based on the deployment of renewable energies in all available territories.

Scarcity of space

Each territory, whatever the geographical scale considered (regional, national, global) must therefore discover its “energy genius” and develop it as well as possible. In this respect, countries and regions are very diverse: Iceland, Gabon, Mauritania, California, Morocco and France do not have the same spectrum of renewable energies.

The use of hydrogen as a fuel (rocket and airplane engines) but above all as an energy carrier, especially for all forms of mobility, offers these renewable energies a very wide range of new potentialities.

But there is no such thing as zero harm: how can we avoid the NIMBY syndrome? At this level, the work of Elinor Ostrom (Nobel Prize in Economics 2009) on the commons and “polycentric” governance complements the approach of the pollution rights market.

More generally, the space allowing the capture of solar energy directly (solar panels) or indirectly (wind turbines of all kinds, use of biomass) is increasingly coveted. The major energy operators are no longer just looking for new deposits of carbon fuels, they are looking for suitable spaces to exploit renewable energies in an optimal way and without causing too much nuisance.

It is therefore space, more than energy, that is becoming scarce: scarce for the installation of wind turbines or solar panels, but also and more generally for conserving arable land and natural areas favorable to biodiversity.

Indeed, all industrialized spaces (“the bony proliferation of factories” wrote Bataille) and those related to consumption, housing, mobility threaten this biodiversity.

Alongside the carbon footprint, which often leads to somewhat obsessive calculations and commitments of little interest, even if they are kept, we must therefore introduce the spatial footprint.

The spatial footprint

The term “spatial footprint” has been used before, but for local calculations. For example, as an indicator of the area allocated to urban transport: road network, parking lots, public transport infrastructure, etc. To this direct spatial footprint can be added the space needed to absorb the CO2 emissions caused by transport. It is also used to evaluate local agri-food supplies or the impact on the ground of mining equipment, etc.

This notion must be extended to all forms of concrete and soil artificialisation that have resulted from the industrial revolution, a revolution made possible by the availability of fossil fuels (coal at the outset). Georges Bataille speaks in this respect of the “bony proliferation of factories”. But it is not only factories that occupy space, it is cities, housing and businesses, roads and other transport infrastructures.

A recent assessment (Nature, December 2020) shows the magnitude of the problem: humans represent only 0.01% of the total biomass of our planet, i.e. of all living things (plants, animals, fungi, micro-organisms). But this tiny part of the living world has produced today a mass of inert matter, called anthropomass, of 1154 gigatons (one Gt = 109 tons) of concrete (549 Gt), aggregates (386 Gt), bricks (92 Gt), asphalt (65Gt), metals, glass and plastic. This mass has become greater than the 1120 Gt of total biomass.

At the beginning of the 20th century, this inert mass represented only 3% of the biomass. If the evolution continues at the same rate, it could represent three times the biomass by 2040. It is difficult to believe that a single species, which represents only 0.01% of living organisms, is transforming the planet’s spatial resources at this rate.

It is thus understandable that biodiversity is not only threatened by climate change but also by this growing mass and, more precisely, by its land use (an urban tower consumes less useful space than a stretch of highway). The same is true for arable land: 0.19 hectares/inhabitant in 2016 compared to 0.49 hectares/inhabitant in 1945 (Le Déméter 2021)[4].

The term Anthropocene (still discussed by the scientific community of geologists) has spread from the climate threat, but the “human era” begins with the industrial revolution and is confirmed in the middle of the 20th century: humans become a “geological force” modifying, disturbing, threatening the biosphere. The formulation seems to me somewhat excessive, presenting the human species “as” a geological force. It is not the planet that is threatened but the biosphere, which is already a lot! The repeated slogan “Save the planet”, which comes directly from climate anxiety, should rather give way to the more modest but more measured “Save the land”. Save the land – land and sea – the arable soil, that scarce resource, to avoid the collapse of biodiversity and agricultural production.

The war for space

Land use will be further accentuated by the energy transition in the coming years, since renewable energies “consume” a lot of space. It is therefore necessary to evaluate this new space requirement and to seek optimal solutions. For the same amount of energy (one terawatt-hour), it takes 89,400 hectares to produce biodiesel from soybeans and 34,710 hectares to obtain ethanol from corn. The land area for wind power is estimated at 7,200 hectares, that of photovoltaics (which is constantly making technical progress) at 3,700 hectares. And that of nuclear power at 49 hectares…

But the war for space goes beyond the energy transition. Breaking the link between fossil fuel consumption and global growth is possible in the long term, but material growth continues to cover the world. Regaining the energy abundance that enabled industrial expansion could even make the situation worse by allowing material expansion to continue largely unencumbered by climate constraints: a successful energy transition to abundant, de-carbonized energy is both desirable and perilous. For the global continuation of growth, in the forms we know today, is impossible.

In the face of a renewed abundance of energy, we must therefore redouble our efforts to shift material growth towards environmentally friendly development. In order to avoid generalities, I will take the example of mobility: the growth of all forms of mobility (cars, trains, airplanes, etc.) is closely linked to material growth (it contributes to about one third of GHG emissions today). We can reduce these emissions (notably through the widespread use of hydrogen). But what must be avoided is the expansion of the road and highway network. If China, India and Africa were to build road facilities comparable to those in Europe and the United States, it would be a disaster.

Fortunately, this seems to be impossible because of the scarcity of marine (or river) sand, which is essential for the manufacture of concrete. It takes 30,000 tons of sand to make one kilometer of road, 12 million tons of sand for a nuclear power plant. Two thirds of the constructions on the planet are made of concrete and two thirds of this concrete is made of sand. In recent years, China has consumed as much sand as the United States did in a century. Today, a “sand war” is raging in the world and is not taken seriously enough.

The mobility of the 21st century will therefore have to be oriented towards spatial sobriety and, for example, favor air transport (drones, hydrogen-powered planes) rather than the extension of road infrastructures. Or recognizing the value of urban concentrations whose footprint, including in terms of mobility, is relatively small (especially if these urban concentrations do not destroy arable land).

All these transformations will require two pillars. One is scientific and technological, the other is symbolic.

At the scientific and technological level, the contribution of rich countries or countries in advanced transition is essential. Making savings and obsessively seeking carbon neutrality is not useless, but it does not meet the challenges. Unless we know how to adapt them and export them to the rest of the world. The main lever remains innovation. In the field of energy, which irrigates the entire economic system, but also beyond (agriculture, housing, transport). A reorientation in favor of green finance is a lever to be favored and it would even be legitimate that, in some cases, current intellectual property rights be reduced to better circulate innovation, particularly in favor of Africa whose energy needs will be immense in the coming years.

At the symbolic level, we need to move away from a quasi-religious perception of the stakes of ecology; we need to stop opposing the economic order and the ecological order, and articulate the two by subjecting the first to the second. More broadly still, we need to articulate competition (which is the basis of the economic order in Europe, then in the West, then in the world), with cooperation, solidarity, the adaptation of development to a finite world, and the promotion of common goods. Promoting the development of life sectors (health, education, research, culture) to limit material growth which, by its spatial footprint, threatens biodiversity and reduces our non-renewable resources.

Nothing less, finally, than to associate Descartes’ project (“to make ourselves as masters and possessors of nature”) based on power, with Spinoza’s search for adequacy, based on power. It is a total reversal of our perceptions and practices and not just a slowing down or a simple reorientation. In 1989, Felix Guattari proposed the concept of ecosophy, as environmental ecology cannot be dissociated from two other ecologies, social and mental.

Ultra-green energies?

To conclude on an optimistic and concrete note, while underlining that the spatial footprint also concerns the oceans.

Healthy oceans play a major role in climate regulation through their function as a carbon pump and oxygen producer thanks to plankton. They contribute to the local, national and global economy with more than 350 million jobs in the world, through aquaculture or biotechnologies.

But marine ecosystems are threatened by deoxygenation. The surface area of oxygen-poor environments has quadrupled in fifty years. The combined effects of nutrient overload and climate change are increasing the number and size of these “dead zones” in open ocean and coastal waters. In these areas, many organisms die of asphyxiation while other species can thrive but at the expense of biodiversity (algal blooms).

Offshore wind platforms could provide a solution. Not only an energy solution (green hydrogen) by electrolysis of water. Electrolysis allows the separation of hydrogen from oxygen, the production of one kilo of hydrogen generating eight kilos of oxygen. The latter can be used to sterilize water (through a process of ozonation) and make it safe and drinkable, which in some countries can be beneficial to public health. It may be possible for the oxygen produced in this way in large quantities to be used for direct environmental purposes. Re-injected into the most depleted marine environments, it can improve these environments, allowing the fauna and flora to revive.

However, these geo-engineering processes must be the subject of in-depth studies and lead to tests carried out in well-chosen and limited areas. Marine ecosystems are complex, their evolution is chaotic (in the mathematical sense) and many hopes have been dashed in this field in recent years. Furthermore, the large-scale implementation of these mitigation processes, for example in the open Baltic Sea, does not depend on one country alone and must respect international conventions.

If these preconditions are met, hydrogen would allow the production and use of energy without environmental impact. And even, which would obviously be spectacular because it would be the complete opposite of oil, with positive effects since its production would offer a way to heal hypoxic sea areas or to accelerate the effects of other treatments. This is why I have coined a neologism: ultra-green energy.

An energy that would protect the ocean, without risks, without major influence on the territory? Impossible to achieve completely, no doubt, but it points in the right direction to save the living world and feed mankind.

Marc Guillaume, Professor Emeritus