Algal farming - a new Agricultural Revolution?

Recent food riots around the globe could spell the end for the biofuels industry based on crops grown on arable land. And although biofuel crops are only partly to blame for skyrocketing food prices, they are already branded by some critics as a crime against humanity.

The dilemma, biofuels or food, disappears as soon we turn our intention to the humble seawater algae. They are not only a potential source of biofuels. Algae are at the base of the marine food web and can also be used for human consumption or as animal fodder. And whatever we do not use can easily be converted into very good fertiliser. Growing algae on barren land may indeed offer a new agricultural revolution and Australia could be at its forefront, earning a good deal from carbon credits.

The world seems blinded by its desire for high-tech solutions. We may be better off adopting large volume, low-tech solutions which any farmer can understand and implement. If they grew algae for fuel, food, feed and fertiliser production farmers could become less dependent on fossil fuels, expensive fertilisers and dwindling fresh water sources. Farmers could also grow fish with the algae on barren land while continuing to grow food crops on fertile parts of their property. Australia’s salinity issue could also be addressed by providing salt water drainages and enabling targeted afforestation.

Unlike in the open sea, we have some control over what we grow in basins or ponds on barren land. This is the basis of my Greening Method (patent pending). As we grow the algae in saltwater ponds, the water will evaporate and this may offset soil humidity loss on nearby land sufficiently to enable vegetation growth. We can also use the grown algae to improve soil fertility and quality. And, once vegetation takes hold, we are ready to grow a new agroforestry mix.
Harvesting ocean algal blooms is also an option. Although we have yet to work out mechanisms that drive them, they too could also be managed as a source of algal oils and carbon credits. For example, existing oil spill containment technologies could easily be adapted for harvesting of algae on the open sea. The fishing industry may also benefit from this as seeding the seas may increase potential fish catches.

The public usually finds the thought of sewage treatment plants distasteful, but these too could play an important role in the envisioned agricultural revolution. Human waste provides primary nutrients to algae and since they are low in food chain we can be quite safe in using it to feed them. We can use the waste from sewage works in two ways: to grow algae for biofuels in specialised treatment plants or to fertilise algal blooms at sea.

People will inevitably raise the issue of the cost of algae-based fuels, but the answer is that political will always plays a key part in how much something costs – a point underlined by the Brazilian ethanol industry which would not have flourished without government support. Costs can be driven down not only by carbon credits, but also by our inventiveness and experience.

Our farmers were quite inventive in the past and they are likely to continue in the future. Algal farming experiences may also become valuable export products earning even more carbon credits. 


Editor's Note: For permission to reproduce this article please contact ScienceAlert.