a b s t r a c t Homogeneous acid catalysts received wide acceptability because of their fast reaction rates. However, postproduction costs incurred from aqueous quenching, wastewater and loss of catalysts led to the search for alternatives. Until recently, heterogeneous base catalyzed-biodiesel production also gained the atten- tion of most researchers. This was because the process minimized the problems of homogeneous catalysis in terms of catalyst regeneration and recycling in continuous processes. However, despite these advances, the ultimate aim of producing biodiesel at affordable cost is yet to be realized. Further, the process requires refined feedstocks which account for as high as 88% of the final production costs. Thus, the focus of many research efforts is towards the rational design and development of solid acid catalysts aimed at reduc- ing biodiesel production costs. Therefore, this study reviewed current literature on the activities and advantages of solid acid catalysts used in biodiesel production. It discussed in details how the prepara- tion method and prevailing reaction conditions affect the catalytic activity of the catalyst. The review concluded by suggesting way forward from the traditional trial-and-error method to a rational means of determining catalytic activities.

Activity of solid acid catalysts for biodiesel production: A critical review

Nowadays, biomass is considered as one of the main sources of energy for both developed and developing countries. Malaysia with a large amount of biomass residues as a source of electricity generation is considered as one of the potential countries in this field. This study aims to analyze the potential of recovering energy from major source of biomass residue in Malaysia. For this purpose, the agricultural crop residues and industrial crop waste are investigated. These will contribute substantially to harness a sustainable resource management system in Malaysia to reduce the major disposal problem of biomass residue. The effective use of the waste can supply the required fuel for future electricity generation.

A review on electricity generation based on biomass residue in Malaysia

The world needs an enormous amount of energy to maintain the future economic developments. India has facile ways to overcome the immediate demand on energy supply by renewable energy resources. It has a huge potential of biomass resources to reduce the dependence on fossil fuels and to produce electrical and heat energy. The biomass energy can contributes to social and economic development. It has been identified as an alternative for the future energy demand in India. As part of furthering the development of biomass technology, it is essential to understand the environmental merits and demerits of biomass. It also aims to increase the use of biomass energy for domestic purposes. The interest behind the review is boosted by the rapid development of biomass conversion techniques and continual increase of biomass energy generation. It has motivated the authors to collect the quintessential literature of environmental aspects of biomass energy. The objective of the research work is to quantify and focuses the environmental performance of biomass energy. It also deals with the environment monitoring and control, pricing, standard and regulations of the bio-energy for the future development.

Quantifying environmental performance of biomass energy

The public opinion on renewable energy technologies was analyzed by means of a survey implemented in Portugal. The survey addresses four technologies: hydro, wind, biomass and solar power. The results show that biomass is the least known technology, while hydro power is the most known. There is a generally positive attitude towards new renewable energy projects, and this tendency is more pronounced for solar power, while the case with lowest but still large support is the one of new hydro power plants. NIMBYism is more pronounced in municipalities with biomass, although not felt by the vast majority of their population. Solar power plants are regarded by the Portuguese public as the most desirable technology in terms of economic and environmental aspects, while hydro power is perceived as the technology that can contribute most to local residents' welfare. Willingness to pay is high among those who perceive renewables as increasing the costs of the electricity, but few respondents believe that renewables tend to raise the electricity bill. This study shows that the Portuguese are generally supportive of the development of more renewable energy projects in the country, and apparently these will not be subject to much local opposition excepting, perhaps, biomass.

Public opinion on renewable energy technologies in Portugal

The electric energy potential of landfill biogas in Brazil

https://repositorium.sdum.uminho.pt/bitstream/1822/19563/3/carneiro_paula_RE_2012.pdf

P. Carneiro

Papers

The economic, environmental and strategic value of biomass