Pond power

A project team is examining ways of cultivating algae to produce oil on a large scale.

Algae could produce sustainable, industrial-scale biofuel if processes being developed in a €6m (£5.3m) Scottish-led research programme prove successful.

BioMara, a collaborative project between Scottish and Irish researchers, is being coordinated by the Scottish Association for Marine Science (SAMS).

The group hopes to better understand the way algae naturally produces oil so it can be stimulated to do this on a large scale.

The resulting biofuel would help meet the European Parliament’s call for 10 per cent of road transport fuel to come from renewable sources by 2020.

Algae is viewed as a promising fuel source because it can generate 30 times more oil per acre than other plants used for biodiesel and other biofuels. Also, algae does not compete with food crops.

The BioMara project has received €4.9m (£4.3m) from the European Union’s INTERREG IVA programme, with additional funding from Highlands and Islands Enterprise, The Crown Estate, the Northern Ireland Executive and the Irish government.

Laila Sadler, a spokeswoman for BioMara, said that biologists at SAMS will research macroalgae, such as seaweed, and microalgae, which are single-cell microscopic algae that grow by cell division.

Sadler explained that, with favourable conditions, a single algae cell will enlarge and divide into two cells that subsequently grow and divide, increasing the culture exponentially.

Microalgae is thought to be the more favourable source because it produces more oil than macroalgae and it is much faster and easier to grow. However, macroalgae can be used as a source for ethanol and methane.

The BioMara team envisage the macroalgae being harvested from sea farms, whereas the microalgae would be grown in a controlled industrial environment. Michele Stanley, lead scientist on the BioMara project, said that the challenge will be to figure out a way to encourage microalgae to divide and grow and still produce lots of oil.

The problem, she explained, is that microalgae usually produce oil only when under physiological stresses such as a lack of nitrogen or wildly fluctuating temperatures. Those conditions are counterproductive to growth.

Stanley said that the team will attack this problem in two ways. ‘We’ll actually grow the microalgae up and let it grow merrily with all the nutrients it needs and then take away the nitrogen source to stress it,’ she explained.

‘Of course you’re going to have lower growth, but you hopefully have enough growth there to compensate for that. It’s a balance,’ added Stanley.

The microalgae would be cultured in large industrial plants, called photobioreactors, which introduce light and CO2 to pools of algae to stimulate growth.

Sadler said that there are at least two companies in Israel researching ways of deriving the CO2 necessary for algae growth from power station emissions.

Israeli company Seambiotic claims to be the first in the world to use discharged gases from coal-burning power station smokestacks for algae cultivation. The company installed eight open algae ponds at the Israel Electric Company power plant in Ashkelon as part of a pilot programme last year.

In the future, these algae ponds will not necessarily need to be collocated at a power plant. With technologies such as carbon capture and storage on the horizon, Sadler believes that CO2 could be pumped from a power station to an algae cultivation plant located some distance away.

In addition to SAMS, the BioMara project includes Strathclyde University, Queen’s University Belfast, Ulster University, the Dundalk Institute of Technology and the Institute of Technology, Sligo.

Siobhan Wagner