Algae as biofuel

Abstract

The combustion of fossil fuels contributes to climate change by introducing greenhouse gases to the atmosphere, and the need for an alternative fuel source is increasingly important. Biomass, either terrestrial or aquatic is considered a potential renewable energy source for biofuel production. Microalgae or seaweed (Macroalgae) are considered superior compared with terrestrial plants – in terms of solar energy storage, nutrient assimilation and potential for biofuel production – due to their higher photosynthetic efficiency, higher biomass yield and rates. The use of algae for biofuel production is expected to play an important role in securing energy supply in the next decades. For example, not only in the processing of those algae directly related to biofuels production but also in the possibility of combining this processing with pollution control, in particular with biological sequestration of CO₂ emissions and other greenhouse gases, or wastewater treatment. Energy from biomass (biological, including biofuels and non-biological processes including gasification, combustion, and so on) is expected to provide more than a half share of the total energy to achieve the desired target. The various aspects associated with the design of algae production units are described in this paper, giving an overview of the current state of development of algae cultivation systems (photo-bioreactors and open ponds). Other potential applications and products from microalgae are also presented in this paper – for example applications in teh biological sequestration of CO₂ and in wastewater treatment. In addition, the use of microalgae as food additives and for aquaculture is also discussed.

Keywords:

• microalgae
• biodiesel
• photo-bioreactors
• open ponds
• transesterification
• CO₂ sequestration