Today's human society depends heavily on fossil fuels such as oil. From transport fuel to petrochemicals, the uses of hydrocarbons are multiple.

Oil is neither inexhaustible nor climate-innocent. It is therefore necessary to anticipate its decline.

Among the alternatives explored (biofuels), the biopetroleum — sometimes presented as “the oil of the future” — aroused a great deal of interest. Overview.

What is biopetroleum?

Biopetroleum is An oil made from microalgae that feed on CO₂. The idea, which was publicized around 2011, generated real enthusiasm.

Manufacturing process

By photosynthesis, microalgae are grown in photobioreactors (tube/transparent), then harvested and filtered into a paste. This paste is then Cracked (high T°/high P) to give a petroleum very close to crude fossil fuel. After hydrotreatment, cuts of hydrocarbons miscible with kerosene, gasoline or diesel are obtained.

The “blue oil” from Bio Fuel Systems

In Alicante, the pilot plant of Bio Fuel Systems (BFS) tested a model consisting of feeding millions of microalgae (from the Atlantic and the Mediterranean) with CO₂ from a nearby cement factory, in ~400 giant tubes. The liquids collected are filtered to obtain a biomass intended for biofuels.

Why microalgae?

A “natural” development

Microalgae, components of phytoplankton, form a biomass at the origin of sediments that have become oil over the ages. A sustainable resource, they grow with sea water + sun, without fertile soils or inputs, in basins or above ground: they do not compete with food (unlike some crops of 1^re generation).

GHG reduction

Composed of ~ 60% sugars, they are suitable for butanol/bioethanol (fermentation) for algae fuels. They capture CO₂ during photosynthesis, potentially contributing to the atmospheric reduction of CO₂.

Very high productivity

Better photosynthetic efficiency than terrestrial plants, continued growth (annual production). Orders of magnitude mentioned: ~6,000 L/ha for palm oil vs ~14,000 L/ha for algofuel (industrial targets up to 60,000 L/ha/year).

... but a process still to be optimized

The current pattern is Energy-consuming (cultivation, harvesting, extraction, cracking, hydrotreatment). Researchers (e.g. INRAE) are questioning the best “way to valorize” algae.

The cost of biopetroleum remains prohibitive: up to ~100× a fossil fuel in the first balance sheets. Advances in scale and processes are needed to aim for competitiveness.

Scientific challenges: reconciling lipid production (often stimulated by stress, which slows growth) and massive growth. Tracks: varietal selection, molecular genetics, processesExtraction that consumes less energy.

In summary — Algal biooil is a promising but still immature approach. If its technological promises are confirmed (efficiency, costs, energy balance), it could become a interesting alternative in a bouquet of low-carbon solutions. To be continued, alongside other levers (electrification, hydrogen, advanced biofuels).

Also to read: Can we supply an entire country with renewable energies?