The Straits Times on Monday published this piece by ISEAS senior research fellow on algae as a source of biofuel.
Swayed by algae’s cool, green potential
DO WE really need to keep pushing the frontiers in the search for oil? Must we venture into ever deeper and more dangerous waters, and into areas on land where technical challenges and political risks are rising?
Some of the world’s leading energy companies evidently believe there may be a promising alternative much closer to home: algae, that slimy scum, often green or brown in colour, that grows abundantly in oceans, along seashores, in lakes, rivers and ponds, basically anywhere there is sunlight.
ExxonMobil said last year that it would invest US$600 million (S$826 million) over the next five or six years to try to produce fuels from algae comparable to those refined from conventional crude oil. Last week, it opened an indoor facility in California to grow and test algae.
Algae biofuels have several attractive features for investors and consumers. Unlike other biofuel sources such as corn, soya beans and sugar cane, algae does not compete with our food supply. Nor is it linked to the cutting and burning of tropical forests, as palm oil is. And because algae absorbs huge amounts of carbon dioxide, the main greenhouse gas from burning fossil fuels, it could help reduce global warming.
Algae also soaks up other pollutants, including oxides of nitrogen and sulphur, both components of acid rain. In addition, algae probably produces around three-quarters of the world’s net output of oxygen in the air we breathe.
Hundreds of firms, in the United States, Europe and Asia, as well as droves of research scientists and engineers, are now involved in the quest to turn algae into a commercially viable fuel source.
BP is planning to divest around US$10 billion in non-core exploration and production assets to help pay for cleanup costs in the Gulf of Mexico in the worst offshore oil spill in US history. Despite this pressure, the company announced last week a significant addition to its biofuel business in the US, saying it had invested more than US$1.5 billion in it since 2006.
Are these just ‘alternative energy’ sops by big oil companies to their critics, while they continue to focus the bulk of their resources on finding and producing conventional oil and gas?
That may be part of the story. But the promise of algae as a renewable fuel source that can combat climate change makes the organisms hard to ignore. They are tiny, biological factories that use photosynthesis to transform sunlight and carbon dioxide into energy so efficiently that they can double their weight several times a day.
As part of this process, algae produces oil. It can generate 15 times more of it per hectare than other plants used for biofuels. Although it comes in many different strains and forms, algae is made up of relatively simple organisms. And it grows in salt water, fresh water or even contaminated water.
However, algae developers face major challenges, which may take anywhere from a few years to a decade or more to overcome. The challenges include sifting through thousands of species to find the right strain of algae that will produce high yields; designing systems in which the desired algae can multiply without other species invading and disrupting the process; and developing efficient harvesting methods to extract oil without damaging other parts of the algae that have useful and potentially profitable functions.
Regulating carbon emissions, making algae production less energy-intensive and cutting its production cost will be critical. US researchers said last year they reckoned it cost about US$56 per gallon to make algae biodiesel, but that as production techniques improve, the cost could fall to around US$5 per gallon. The average retail price of regular diesel in the US today is about US$3 per gallon.
Earlier this year, American scientists published a study of pilot projects for producing algae in the past 15 years. It showed they consumed more energy, had higher greenhouse gas emissions and used more water than other biofuel sources, such as switchgrass, canola and corn.
Still, the potential benefits remain great and production techniques are being refined. The most common ways of growing algae are in open ponds and enclosed containers called bio-reactors. The latter harness reflected sunlight so that algae growing on membranes can use plant photosynthesis to produce energy, with oxygen and water vapour as the only waste products.
Martec Biosciences Corp in the US formed a joint venture with BP last August to mass-produce a third algae production system, with fermenters that are 4m in diameter and five storeys tall. Meanwhile, Exxon has teamed up with Mr Craig Venter, the US genomics pioneer, to test whether large-scale quantities of affordable fuel can be produced from algae.
Mr Venter says that while thousands of natural strains of algae are being screened, the sheer number of requirements for success means that at some stage chosen strains will probably need genetic modification.
Welcome to the brave new world of bio-engineering that may one day free us from dependence on imported oil.
The writer is a visiting senior research fellow at the Institute of Southeast Asian Studies.