Lauro André Ribeiro

A biorefinery from Nannochloropsis sp. microalga – Energy and CO2 emission and economic analyses

Are microalgae a potential energy source for biofuel production? This paper presents the laboratory results from a Nannochloropsis sp. microalga biorefinery for the production of oil, high-value pigments, and biohydrogen (bioH2). The energy consumption and CO2 emissions involved in the whole process (microalgae cultivation, harvest, dewater, mill, extraction and leftover biomass fermentation) were evaluated. An economic evaluation was also performed. Oil was obtained by soxhlet (SE) and supercritical fluid extraction (SFE). The bioH2 was produced by fermentation of the leftover biomass. The oil production pathway by SE shows the lowest value of energy consumption, 177-245 MJ/MJ(prod), and CO2 emissions, 13-15 kgCO(2)/MJ(prod). Despite consuming and emitting c.a. 20% more than the SE pathway, the oil obtained by SFE, proved to be more economically viable, with a cost of 365€/kg(oil) produced and simultaneously extracting high-value pigments. The bioH2 as co-product may be advantageous in terms of product yield or profit.

Technoeconomic Assessment on Innovative Biofuel Technologies: The Case of Microalgae

Innovative technologies and sources of energy must be developed to replace fossil fuels and contribute to the reductions of emissions of greenhouse gases associated with their use. In this perspective, algal biofuels are generating substantial awareness in many countries. As of today, it has been shown that it is scientifically and technically possible to derive the desired energy products from algae in the laboratory. The question lies, however, in whether it is a technology that merits the support and development to overcome existing scalability challenges and make it economically feasible. In this context, the overall purpose of this study is to provide an integrated assessment of the potential of microalgae as a source to produce biofuels, while confronting it with competing emerging biofuel technologies. It is intended to provide a comprehensive state of technology summary for producing fuels from algal feedstocks and to draw some insights upon the feasibility and technoeconomic challenges associated with scaling up of processes.

The role of microalgae in the deployment of biofuels: contrasting algae and solar technologies

With this study, it is aimed to provide an integrated review of the likelihood of microalgae deployment in the framework of biofuels production, while confronting it with emerging technologies, namely solar power. In this framework, a comparison study between the evolution of solar energy and algae biofuels will be made to draw lessons for what could be a possible success path of microalgae biofuel technology. This paper presents a discussion of the ongoing development of policies to optimise production and to encourage emerging energy technologies. To provide insightful arguments, this paper builds upon the Strategic Energy Technology Plan (SET Plan) and the European Directives, 2010 scenarios made available by the International Energy Agency regarding energy technologies perspectives, among scientific state-of-the art literature.

Qualitative Delphi approach of advanced algae biofuels

Purpose – Currently, experimental and theoretical work is being performed to ensure that biofuels from microalgae become a reality. However, there is a considerable number of discussions concerning in which processes should be focussed efforts of research and development. The purpose of this paper is to provide decision support not only to help build guidelines of research to be undertaken, but also to contribute to the design of more adequate policy and funding instruments. The key objective of this study is to determine the prospects of employing microalgae into the production of biofuels within a time scale extending to 2030. Design/methodology/approach – The Delphi method is a qualitative research aiming to support strategic future-oriented action, such as policy making in the areas of science and technology. It is especially appropriate in judgment and long-range forecasting (20-30 years) situations, when expert opinions are often the only source of information available, due to a lack of appropriate...

Algae: Advanced Biofuels and Other Opportunities

Despite the challenges, depending on the local conditions and practices, renewable energy sources are already a significant contribution to the energy mix. Although this is true for electricity generation, the same does not apply for the transportation sector, where the available renewable sources are limited and still have a modest impact in the overall consumption. In this context, advanced biofuels such as microalgae are worldwide believed to be a better choice for achieving the goals of incorporating non-food-based biofuels into the biofuel market and overcoming land-use issues. Compared to other biofuel technologies, the most favorable factors for the cultivation of microalgae for the production of biofuels are they can be grown in brackish water and on non-fertile land, and the oil yield production is far superior. Main challenges are currently the feasibility of large-scale commercialization, since the majority of economic and financial analyses rely on pilot-scale projects. Environmental issues are most likely to diverge opinions from experts. This chapter presents a review of microalgae cultivation (species, usage, processes, and culture) and biofuel production, highlighting advantages and challenges of algae biofuel.