Most biofuel is produced by plants such as soy, palm oil and corn-based ethanol, but the high water use, deforestation and energy consumption associated with its production often outweigh the benefits of using it. More often associated with beer and bread than biofuel; and so yeast may be the surprising candidate for a more sustainable energy source.
At The University of Texas at Austin’s Cockrell School of Engineering, researchers have created a highly efficient biofuel using genetically engineered yeast cells. Grown directly from sugar and without the need for nitrogen starvation (that traditional growing techniques rely on), the genetically engineered Yarrowia lipolytica strain was able to produce 90% yield of the oils and fats known as lipids; the highest level of lipids ever produced by yeast fermentation.
“To put this in perspective, this lipid value is approaching the concentration seen in many industrial biochemical processes,” explains Assistant Professor Hal Alper. “You can take the lipids formed and theoretically use it to power a car.” Another benefit of this new energy source is that it would not compete with land and could be grown anywhere, making it a more attractive alternative to other biofuels, such as soybean and flax oil.
Oil Company Shell and the Biotechnology and Biological Sciences Research Council funded research undertaken by the University of Exeter to produce bio-diesel using a strain of E.Coli that is compatible with modern engines.
Professor John Love from University of Exeter said, “Rather than making a replacement fuel like some biofuels, we have made a substitute fossil fuel.”
This was achieved by altering the bacteria so that it converted sugar into synthetic fuel. The researchers believe that something that mimics fossil fuels would be seen as a more attractive option to both manufacturers and consumers. “Read more here
The idea is that car manufacturers, consumers and fuel retailers wouldn’t even notice the difference – it would just become another part of the fuel production chain,” states Professor John Love. However, the team admit that they need to improve the yield, as it takes 100 litres of bacteria to produce a teaspoon of fuel.
The financial viability of producing and using biofuels and the amount of time that needs to be invested into scaling production from lab to petrol pumps is considered as one of the biggest barriers to the development of new alternative biofuels. A 2010 study carried out by the Lawrence Berkeley National Laboratory suggested that a barrel of fuel produced from algae would cost between $240 and $332 per barrel.
“Algal biofuels cannot compete with fossil energy based on simple economics,” states John Benemann, an industry consultant. However, “an oil field will deplete eventually, while an algae pond would be sustainable indefinitely.” Read more about environmental benefits of algae from here
Supplies of oil, gas and coal are dwindling, which means that it is becoming increasingly important to find an alternative energy source. Biofuel certainly has its drawbacks, but fossil fuels are finite, which means that eventually, alternatives will have to be used. Whether it is biofuels, electric or hydrogen powered vehicles, the consumption of energy and humanity’s relationship with transportation will also have to be re-examined as part of a more sustainable future.