Algae. Some are green, some are red, some are brown. Some are slimy, tiny or huge. On first glance, you would think that they don’t do much, that they just sit there passively waiting out life’s storms and seasons. But on a microscopic level they come to life. Each algal cell has the fundamental organelles which help with the cell’s day to day running, such as a nucleus, mitochondria, ribosomes (the control centre, powerhouse and protein construction workers of the cell) . But they also contain chloroplasts. These little photosynthetic factories house chlorophyll molecules which ultimately absorb energy from light and turn it into sugars.
Scientists have taken advantage of these little sugar-making factories, and in turn tried to create a renewable alternative to fossil fuel. The result? Algae biofuels. Today, the two main production systems used are open pond systems and closed photobioreactors. Open ponds are basically huge ponds (artificial or natural) filled with algae. Contamination is a risk, so algae strains that are able to dominate wild strains of algae are preferable. With closed photobioreactors, the algae ‘soup’ is contained in a network of small clear tubes, which are exposed to light. These can be very expensive to build and maintain.
Rapid algae growth is further encouraged by the addition of sugars, CO2 and nutrients such as Nitrogen, Phosphorus and Potassium. Under these conditions, algae production can be all year round. Once the algae has grown to the desired quantity, it is collected and separated from its water solution. Once the algae has dried, the lipid content is extracted to make biodiesels. The carbohydrate biomass of algae can also be fermented to produce bioethanol. The great thing about algae biofuel production is that it reduces competition for arable land and fresh water resources, since algae can grow in brackish water, saline or wastewater.
Studies have been conducted around the world, and theoretical findings suggest that algae biofuels have the potential to produce between 10 and 100 times more fuel per unit area than other biofuels. If this can be confirmed on a commercial scale, we may have found a possible solution to our diminishing fossil fuel crisis. The high-oil productivity of algae biofuels makes it an even more desirable alternative fuel. Algae with high-oil production are reported to generate more than 50,000 Litres of oil per hectare, per year. To produce this amount of oil, the amount of arable land (in the U.S.A.) necessary for algae biofuels would amount to less than 2.5%. And the resulting biofuel would cover 50% of US transport fuels! Now that’s what I call a pretty nifty turnover.
This is only a snippet of all the amazing things that can be achieved using algae. Development of algae biofuels is not an immediate solution to fossil fuels, but it is a start. By alleviating some of the environmental pressures associated with fossil fuels, and utilising natural resources in a healthier way through biofuel production, maybe we can meet rising world energy demands, and still create a better, cleaner future.
In the meantime, maybe I’ll set up my own backyard algae biofuel lab.