Producing algae biofuel to solve the problem of energy shortage
The Chitose group in Japan are using algae to develop a biojet fuel in an attempt to reform the aviation industry. Their aim is to sustainably mass produce algae using solar energy at a low cost in order to produce a fuel which is eco friendly but also economically attractive, by being price competitive with fossil fuels.
Currently the aviation industry relies on petroleum jet fuel which, being a fossil fuel, is an unsustainable and heavily polluting form of energy which has significant impacts on global warming and climate change. An eye-opening statistic from the WWF demonstrates the impact of the aviation industry: if the aviation sector were a country then it would be one of the top 10 most carbon-polluting nations on the planet. However, increasing awareness about the aviation industry and pressures from environmentalists are creating a push towards more sustainable forms of fuel. This means that the demand for cost-effective environmentally-friendly fuels is rising rapidly.
The advantages of using algae, and more specifically micro algae as a fuel is that it can be cultivated very rapidly, without large amounts of land use, without freshwater and without damaging production processes. Microalgae can even be grown in non-potable saline water and wastewater.
The reason microalgae is preferred over normal or macro algae is because it produces large amounts of triacylglycerol in comparison and so microalgae has a higher potential of success in the biofuel industry. The algae produces lipids (oil) which can then be used in place or adjunct to petroleum. This type of fuel can be used in existing jet engines without or with limited modifications so new technology does not have to be developed for its use to become widespread. In fact, microalgae biofuel has already been tried and tested on a smaller scale with promising results. Microalgae can also be cultivated in unique growing conditions to produce hydrogen gas which could have many uses in the future of hydro-powered vehicles and hydrogen fuel.
One current issue with microalgae as a biofuel is that some species have a relatively low lipid content and so are not as energy-dense as other fuels. This would mean that larger quantities of fuel would have to be stored to cover the same distance in flights. However, current technology can be used to increase the lipid yield e.g. through nutrient starvation. This puts the algae under stress, causing them to accumulate more lipid stores as a quick release energy source and hence making the algae a more efficient biofuel.
Although this technology is not far off and may see its place in the future of the aviation industry, at the moment there are still some challenges to overcome. The oil must meet certain criteria to be used in commercial airlines, the extraction of oil from wet micro-algae can be challenging and costly and it is difficult to continuously mass produce algae. With many companies like the Chitose group working to tackle these problems, we can hope that more sustainable and environmentally friendly alternatives to the currently used petroleum fuel in the aviation industry will become commonplace in the near future.
Sources: Science Direct