Algal biodiesel - a worthy successor of fossil fuels?

Could harvesting biodiesel from algae provide a sustainable solution to the world's fuel crises? Researchers in the CSIR's bioprocessing development research group have embarked on a project to answer this question and present algae as an alternative energy source for Africa.

"Algae have long been known to produce lipids that can be used for biodiesel production," says Dheepak Ramduth, the lead researcher on the project. "With the current worldwide focus on cleaner fuels and environmental awareness, algal biodiesel is an attractive option, as the specific production of oil per unit biomass is extremely high in algae compared to most seed crops. Current biodiesel technologies utilise oil seed crops that are either food crops themselves or could potentially compete with food crops for limited arable land and hence threaten food security in the country," says Ramduth.

The team, under the guidance of Raj Lalloo, undertook desktop studies last year and commenced with laboratory research at the beginning of this year. "In 2006, a preliminary techno-economic assessment of a proposed process indicated a promising option for the production of biodiesel from algae, especially as mineral fuel prices continue to rise. We have thus embarked on a screening exercise to isolate indigenous algal strains capable of producing high levels of biodiesel-related lipids," explains Lalloo.

"The main driver behind this is to generate new knowledge and a potential competitive advantage for the local manufacture of biodiesel."

A wide range of algae has been shown to produce lipids from solar energy, carbon dioxide and an appropriate water source such as wastewater. The lipids are stored in lipid vesicles as energy reserves and can comprise up to 60% of the dry weight of the algal cell. According to Ramduth, in addition to the screening exercise, the Modderfontein-based group will investigate applied biotechnology options for the enhancement of lipid production through organism improvement, development of knowledge of the metabolic enhancement of lipid production and the integration of competitive processes into existing carbon challenges, such as flue gas generated as emissions in electricity production and the growth of algae on industrial and domestic effluent streams.

The CSIR has invested R1,4 million into this project that culminates in 2009 and is also collaborating with the Durban University of Technology. Funding for the following years has not been secured and the aim is to attract other external funders to streamline the research and development process.

Lalloo's group has been involved in algal technology development since 2000, and has researched processes for production of Spirulina, astaxanthin and beta-carotene. He is optimistic that like the beta-carotene production venture that was established in Upington, Northern Cape, with CSIR knowledge, the algal biodiesel project will also provide more than technology and skills.

"The CSIR is aware of the environmental, skills development and job creation competitive advantages. We aim to develop a process for the production of biodiesel from algae so that the positive advantages of South Africa's climate and socio-economic needs can be addressed harmoniously for development of a new biotechnology-based industry." - CSIR

 

December 2007