Rocket launches could be made more ecological. It would indeed be possible to manufacture a bio-fuel using a antifungal molecule produced by bacteria Streptomyces. In a press release, the researchers indicated that the bio-fuel could have much more energy density than the fuels used today.
Jay Keasling, CEO of Joint BioEnergy Institute of the United States Department of Energy and project manager, explains that bio-fuels would be produced from of a bacterium nourished with vegetable matter. Their use in rocket engines will significantly reduce the amount of greenhouse gases released.
At the moment, the project is only in its infancy. However, scientists indicate that the results obtained so far are very promising.
The characteristics of bio-fuel
With global warming beginning to show its detrimental effects, some environmentalists are pointing the finger at the space industry, especially with the ever-increasing number of launches. Although most rockets use liquid hydrogen and liquid oxygen, they can still be equipped with external boosters using less environmentally friendly products.
According to the researchers responsible for developing the new bio-fuel, it would be extremely energetic and might even boost rockets beyond their current capabilities. The basic molecules of ecological fuel are called POP-FAMEs or “polycylcopropanated fatty acid methyl esters”.
The structure of these molecules includes triangle-shaped triple-carbon rings that constrain the carbon bonds to form extreme angles of 60°. This constraint produces high potential combustion energy. The unusual structure also allows molecules occupy a relatively smaller volume.
After having made an inventory of the genomes of the bacteria of the species Streptomyces to find those that could be used in rocket fuels, scientists discovered the “required ingredients” to POP-FAMEs in strain S.albireticuli.
The obtained results
The next step for the team is to produce enough molecules for field testing. These tests generally require at least 10 kg of product.
For now, the results obtained come from simulations. The data collected suggests that POP-FAMEs could generate an energy density of 50 megajoules per liter after chemical treatment. This value is higher than the density generated by gasoline which is 32 megajoules per liter and that generated by RP-1 based on kerosene which is 35 megajoules per litre.
Currently, scientists are working to increase the production of the bacteria in order to begin combustion tests. They are also trying to create molecules of different lengths with a view to applications in solid-fuel rocket engines, in aircraft engines, but also in diesel engines.