Two scientists claim that algae cultivation for fuel production could become viable in 10-15 years. (Photo: Wageningen UR)
Micro-algae production of sustainable biofuel coming
Friday, August 13, 2010, 22:50 (GMT + 9)
Two researchers say producing sustainable and economically viable biodiesel from micro-algae on a large scale will be feasible within 10-15 years. Technological innovations in this timeframe are expected to enlarge the scale of production threefold and cut production costs by 90 per cent.
Professor René Wijffels and Dr Maria Barbosa from Wageningen UR (University & Research Centre) published their article in Friday’s Science, where they thoroughly explain how to reach the biodiesel goal.
They wrote that Europe should be able to become sustainably independent of fossil fuels and even generate sustainably sourced food by producing microscopically small algae in bulk in large-scale installations. The cultivation of algae could be done by extracting fertilisers (nitrogen and phosphates) from manure surpluses and wastewater, and CO2 would come from industrial remains.
Sunlight feeds algae, sustainably breeding biodiesel and almost limitless protein and oxygen. And because seawater can be used, fresh water use would be minimal.
Wijffels and Barbosa describe how based on calculations on energy consumption in transport in Europe, nearly 0.4 billion m3 biodiesel would be required to substitute all transport fuels. Micro-algae cultivation takes 9.25 million ha of land assuming a yield of 40,000 l of biodiesel per ha.
Algae beat agricultural crops like oilseed rape at converting sunlight and fertilisers into usable oily compounds, as full sunshine is not needed. It is thus possible to produce 20-80,000 l of oil per ha versus 1 ha of oilseed rape or oil palm generates only 1500 or 6000 l, respectively.
The world now produces 5000 tonnes of algae (dry matter) worth EUR 250/kg, expensive because algae can make rare substances like carotenoids and omega 3 fatty acids, which get turned into high-quality products like food supplements. Although palm oil costs just EUR 0.50 /kg) as a fuel, fuel crops are controversial.
A feasibility study done on scale enhancement in algal cultivation showed that the current cost price could be cut to EUR 4/kg or even EUR 0.40 /kg by using residues such as wastewater and CO2 from exhaust gases, enhancing the technology and moving production to sunnier countries.
But even that production would not be financially viable -- that would take the use of whole algal biomass. At EUR 1.65/kg, enough to run production on a large scale, it would consists of about 50 per cent oil, 40 per cent proteins and 10 per cent sugars.
If all transport fuels in Europe were replaced by algal oil, 0.3 billion tonnes of protein would also become available -- 40 more times than the amount of soy protein Europe imports yearly.
Also, cultivating algae in seawater would require only 1.5 litre of fresh water/kg of product versus 10,000 litres per litre of fuel from agricultural crops.
Assisted by sunlight, algal growth needs 1.3 billion tonnes of CO2 (Europe produces 4 billion tonnes/year largely from fossil fuels) and 25 million tonnes of nitrogen (of which 8 million would come from wastewater and fertilisers).
A sustainable pilot-study plant AlgaePARC (Algae Production and Research Centre) will soon launch in Wageningen.
- USD 24 mln invested in algal biofuels research
- Over USD 31 mln invested in algae biofuel
By Natalia Real