1. Living organisms, a source of energy and materials

For thousands of years, humanity has depended on resources from the living world, known as biomass. Before the industrial era, this biomass was the main source of energy and materials:

• wood for heating and construction;
• plant fibres (flax, hemp, cotton) for clothing and rope;
• animal materials such as leather and wool for shoes and clothing;
• natural oils and fats for lighting and personal care.

The carbon footprint of biomass is considered neutral, provided that the rate at which it renews itself is sufficient to offset its use. This is the case for agricultural biomass, which renews itself annually, but less so for forest resources, which take longer to regenerate, especially as they are impacted by climate change. On the contrary, the use of fossil fuels (coal, oil, natural gas) releases carbon stocks that have been accumulated over millions of years in plants (for coal) or plankton (for oil) and cannot be replenished.

Today, biomass is regaining interest with the development of bio-based products, made from materials derived from living organisms: plants, micro-organisms and even organic waste.

Using biomass means replacing fossil-based products with alternatives that emit less CO₂ in order to limit environmental impacts and reduce dependence on non-renewable energies.

2. Biomass today: a renewable resource to be rediscovered

Biomass refers to all organic matter (i.e. matter that comes from living beings), which is primarily used for food, but can also be used as a source of energy or raw material. It comes in many forms:

• Plant biomass: cultivated plants, agricultural residues (straw, stalks), forest resources (wood, branches, chips, sawdust) and algae, etc.
• Animal biomass: excrement (slurry, manure), animal fats and fishing residues, etc.
• Organic waste: food scraps, grass clippings, dead leaves, etc.
• Microorganisms: bacteria, yeast, fungi, used in many processing methods.
   

Rich in sugars, lipids and proteins, biomass offers a wide range of molecular building blocks that can be used to design new products. However, unlike the carbon contained in fossil resources, which can be exploited directly, the carbon derived from living organisms is found in more complex biological structures. Researchers are therefore working to develop processes that break down these structures and make optimal use of each component of biomass, without waste.

Among the various sources of biomass, certain plants play a key role in providing important raw materials:

• Sugar plants rich in sugar (beet, sugar cane) and rich in starch (wheat, corn, potatoes);
• Oil-rich oilseed plants (sunflower, rapeseed, soya);
• Lignocellulosic resources rich in complex sugars such as cellulose (wood, straw, flax, hemp).

3. Transforming living matter: from biomass to bio-based products

The European Commission defines bio-based products as non-food products derived from biomass.

The manufacture of bio-based products is not new, but current research aims to master the transformation of biomass to create innovative and sustainable products.

There are many applications:

• Energy: production of biogas and biofuels (for aviation, road or maritime transport). There are three generations of biofuels, depending on the origin of the biomass used:
  • First-generation biofuels from food crops (beet, maize, rapeseed)
  • Second-generation biofuels produced from lignocellulosic residues and waste
  • Third-generation biofuels produced from microalgae in photobioreactors, still under development.
• Construction: manufacture of insulation, paints and adhesives;
• Packaging: development of bioplastics;
• Textiles: creation of bio-based materials;
• Automotive and aeronautical industry: composites, oils and lubricants;
• Fine chemicals: formulation of paints, resins, adhesives, hygiene products, cosmetics, maintenance and cleaning products, pharmaceuticals.
   

Biomass conversion relies on physical, chemical and biological processes:

• Pyrolysis: a process that involves heating organic matter to very high temperatures in the absence of oxygen. For example, wood pyrolysis to produce charcoal.
• Methane production: the decomposition of organic matter, such as food or agricultural waste, by microorganisms in the absence of oxygen. It produces biogas (CH₄ and CO₂) and a residue called digestate.
• Methanation: a chemical or biological reaction that combines CO₂ and hydrogen (H₂) to produce methane.
• Fermentation: a biological process in which microorganisms (such as yeast or bacteria) convert sugars in the absence of oxygen. It is used, for example, to ferment sugars from barley in beer production, or sugars from beet and maize to produce bioethanol.

Among these methods, biotechnology is playing an increasingly important role. It uses living organisms — microorganisms or enzymes — as veritable ‘cell factories’ to produce molecules of interest. These processes draw on a variety of disciplines: molecular and cellular biology, biochemistry, microbiology, bioprocesses, synthetic biology, bioinformatics, etc.

Biotechnology offers a major advantage: it replaces heavy chemical processes with biological reactions, thereby reducing energy consumption, waste and pollutant emissions while promoting the use of renewable resources.

Another important process is chemical catalysis. This involves the use of catalysts – substances that are generally metallic, mineral or organic – which facilitate the conversion of molecules. They accelerate chemical reactions that would otherwise be too slow or inefficient. Chemical catalysis also reduces energy requirements, making it a key process for developing more resource-efficient processes.

4. Towards a bioeconomy that supports ecological transition

Beyond the production of bio-based products, biomass conversion is part of a broader dynamic: that of the bioeconomy. This model aims to use biological resources to build a sustainable, circular and carbon-free economy. The bioeconomy has many ambitions:

• Reducing dependence on fossil resources and strengthening industrial sovereignty;
• Reducing CO₂ emissions and negative impacts on the environment;
• Developing new local industrial sectors and training new professionals in emerging professions in the sector.

Biomass and biomass-based products are therefore essential levers for a successful ecological transition and for building an economy based on living resources. However, this transition to the bioeconomy requires profound changes involving economic actors and public authorities in order to support research, assist in the establishment of industries and define standards that promote the development of bio-based products.

5. The central role of research

While the idea of replacing petroleum with plant-based products seems simple, the scientific and technical reality is much more complex. Biomass is a highly heterogeneous, perishable and difficult-to-process resource: its composition varies according to species, season and growing conditions, and it contains a mixture of sugars, lignin, proteins and lipids that are difficult to separate.

Research therefore plays a key role in:

• Understanding the structure of biomass and identifying more efficient processes for using it without wasting it;
• Improving production processes by optimising microorganisms and enzymes and developing synergies between chemical and biological catalysis in order to overcome scientific and technical barriers, increase yields, reduce energy and water use, and ensure large-scale economic viability;
• Develop products that are competitive, both economically and ecologically, and can be produced without competing with food or other more relevant uses.

Beyond simply replacing petrochemicals, research is paving the way for new molecules and materials: biodegradable plastics, non-toxic solvents, natural additives, etc. These innovations offer unprecedented properties and contribute to building a sustainable, inventive and efficient bioeconomy.