The question whether the production of biodiesel from plants that grow on land is sustainable, is where opinions differ. That is why researchers have turned to microalgae to find a more sustainable solution.
Biodiesel is a biofuel that is produced from different oil sources, such as grease, waste oils, animal fats, but mostly vegetable oils. The use of plant-derived oils however, has become controversial, because it shows to be less sustainable than originally hoped. Especially, since cultivation of plants for biofuels has been linked to shortages in some foods and to rising food prices, increased consumption of water, degradation of arable land and deforestation. For these reasons, researchers are looking for alternative, both sustainable and economical sources of oils for biodiesel.
Claudio Fuentes-Grünewald is doing his PhD between the Institute of Marine Sciences (CSIC) and the Autonomous University, both located in Barcelona, Spain. His research is partially funded by the National Commission of Scientific and Technological Research (CONICYT) in Chile. The project is focused on several species of microalgae from the group of dinoflagellates. Dinoflagellates are mostly marine microalgae. Their name comes from the Greek word “dinos”, meaning “whirling”, and Latin flagellum, a diminutive term for a whip, relating to the two tail-like structures, flagella. The work by Fuentes-Grünewald was recently published in the
Journal of Industrial Microbiology and Biotechnology.
Microalgae are tiny algal species, generally smaller than a point of a needle, consisting of only one cell. They are very important for life on earth, as they produce approximately half of the atmospheric oxygen. Additionally, they can contain high amounts of oils. Researchers have estimated that they could potentially produce 30-fold more oil per hectare than terrestrial plants. This makes them very interesting for the production of biofuels. And there would be even further advantages. Microalgae could be cultured on non-agricultural land and marine species even without freshwater. That is why researchers like Fuentes-Grünewald are trying to find the ideal species of microalgae for biofuel production.
Fuentes-Grünewald’s lab grew the different algae in seawater for seven weeks and recorded their growth rates and weights. Afterwards, the amount of oil in the cells was measured and the oils were extracted. The researchers found that especially the species
Karlodinium veneficum, but also several others could be of high interest as a source for the production of biodiesel, because they grow relatively fast and in high densities, have a short life-cycle and contain high amounts of oils.
“We think that the use of microalgae is the only sustainable way to replacing fossil fuel,” Fuentes-Grünewald told Checkbiotech. “The first biodiesel generation is too controversial and the use of terrestrial plants is less productive, because they use just 1-3% of the total energy from the sun, microalgae can use at least 15% of the energy.”
“Further, the technology to produce high amounts of algal biomass, such as photobioreactors, or open ponds or a combination of both, can be developed quickly and is not restricted to a specific area in the world.”
However, before the technology can be applied on a large scale, there are two major hurdles to overcome. The principal bottleneck of the technology is to find a better way to separate the algae from the water they were grown in. So far, the known methods are very energy-intensive – it is currently necessary to invest more energy into this process than can be gained by using the resulting biodiesel. In addition, the production of biomass from microalgae is very costly, one liter costs around five euros (intensive method). To become viable, the production of one liter should lie below one euro.
Additionally, to produce biodiesel in an even more sustainable way, its production could be combined with other processes. This could comprise the use of carbon dioxide from a thermoelectrical power plant or other industrial carbon dioxide emitting sources. In addition, the employment of the algae for wastewater treatment to clean the water and save on addition of nutrients, before harvesting the algae for the production of biodiesel would also help reduce costs. Another plus is once the oil has been removed, the rest of the algae can be further digested, which then could also be used as a biofuel or to generate electricity.
Currently, Fuentes-Grünewald is writing a second publication about how physical and chemical factors can enhance the oil content in microalgae. He is enthusiastic about the progress. “We have very interesting results. If in a near future we can overcome the energy problems to produce oil from microalgae, we will be ready to work with the most suitable microalgae strains and try to identify the best processes to enhance oil production.”
When Checkbiotech asked Fuentes-Grünewald about the challenges in the production of biodiesel from microalgae, he noted he is optimistic that they will be overcome soon and that biodiesel from microalgae will become a reality. “I assume that in the next five years, different groups and countries will produce biodiesel from microalgae through an industrial process.”
Source:
C. Fuentes-Grünewald et al. Use of the dinoflagellate Karlodinium veneficum as a sustainable source of biodiesel production.
Journal of Industrial Microbiology and Biotechnology.
doi: 10.1007/s10295-009-0602-3
http://www.ncbi.nlm.nih.gov/pubmed/19536573?ordinalpos=2&itool=EntrezSys...
Contact:
C. Fuentes-Grünewald
Institut de Ciències del Mar
Consejo Superior de Investigaciones
Científícas (ICM/CSIC)
Passeig Marítim de la Barceloneta
37-49, 08003 Barcelona, Spain
cfuentes@cmima.csic.es
Universitat Autònoma de Barcelona
Institut de Ciència i Tecnología Ambientals
08193 Bellaterra (Cerdanyola del Vallès)
Barcelona, Spain
Eva Vojtech is a Science Journalist for Checkbiotech and has recently finished her doctorate in Environmental Sciences at the University of Zurich, Switzerland. Contact her at eva.vojtech@gmx.ch.
