Technology Idea of the Week

Green slime! Who says that renewable energy can't be attractive. I think there is something uniquely beautiful about the bright green fields of algae at the Parabel (formally called PetroAlgae) site in Florida.

Parabel HQ in Florida - courtesy of Parabel

Using algae as a biofuel instead of crops hit the news a couple of years ago and I wanted to catch up with what has happened since.

Extensive research into Algae took off in America during the 1950s and 60s. This was largely driven by concerns over a food supply crisis but researchers soon began to discover the other possibilities that algae offered. A paper by Weiss, 1952, Scientific American highlighted the potential as a food source, fertilizers and possibly a fuel. Further research into methane production from algae by Meier, 1953, Agriculture Journal was discussed at a solar energy symposium and the interest in algae grew.

However for the next few decades, efforts to use algae as a biofuel on an industrial scale were pretty stagnant. This can be largely linked to the economical viability of algae compared to fossil fuels and the interest in nuclear energy. The 1974 Energy Review carried out by Nature mentioned solar, wind, nuclear fusion and natural gas (Nature, 1974) but as Dr Umakantha of Karnatak University pointed out: it failed to mention algae (Letters to Nature, 1974).

Not until the last few years has research into algae as a biofuel really gained support again. We can probably link this to two key points. Firstly, the price of oil has now increased over $100 a barrel (Oil Price International) and is reaching the point of becoming commercially not viable. Secondly, the pressure on governments to meet carbon targets continues to grow (UN Conference on Climate Change, 2013). So why isn't everyone growing green energy?

Challenges to Industrial Scale Production of Algae - Summarised from (American Chemical Society, 2009)

• Space - algae require light to grow so you need a high surface area which is expensive
• Sunshine - constant bright sunshine is needed for high level growth rate required to make farming algae viable. Fine if you are in California but probably not in London!
• Strains - there are more than 3000 different strains of algae, understanding which are the best for energy production and how to cultivate them is still not fully understood. 
• Systems - a lot of research has been carried out into the algae themselves but much more R&D is required into the processing systems on larger scales
• Species Invasion - keeping the algae ponds free of invasive species or unwanted algal strains is challenging

Is there a future for algae? 

There is a growing of investment in algae. Investment by big chemical companies such as Chevron and Dow Chemicals in algae research facilities has dramatically increased in the last decade. For example in 2009 BP invested $10 million in Martek Sciences Corporation (Mascelleri, Chemical Journal, 2009).

There is a lot of research into alternatives uses of algae. The University of Bath has produced research into using algae to clean water (Scott et al, 2012). This could help improve efficiency and reduce carbon consumption of water treatment plants. 

There is still a potential for using it as a fertilizer on a wider scale. Algae can be up to 30 times more productive than oilseed crops such as palm and soy (Gabel, 2012). Therefore its potential as a food source, animal feed or fertilizer could be very significant in the future.