scholarly journals Systematic review and perspective on the progress of algal biofuels

2021 ◽  
Vol 257 ◽  
pp. 03008
Author(s):  
Muxin Hu ◽  
Dichen Zhao ◽  
Qiuchi Jin ◽  
Hanrui Li ◽  
Wenmin Wang

In recognition of the increasing demand of energy and the worsening environmental problems linked with fossil fuels usage, algal biofuel has been proposed as one of the alternative energy sources. It has become one of the hottest topics in renewable energy field in the new century, especially over the past decade. In this review, we summarized the characteristics of different types of algae biofuels. Besides, an in-depth evaluation of the systematic cultivation and practical application of algae have been conducted. Although algal biofuel has a great potential, its unacceptably high cost limits the large-scale industrialization. In order to resolve such restrictions, feasible methods of improving the large scale production and practical application of algal biofuels are proposed. Future efforts should be focused not only on the cost reduction and innovation techniques, but also towards high value by-products to maximize economic benefits. Our results are dedicated to provide valuable references for subsequent research and guidelines on algae biofuels field.

2012 ◽  
Vol 260-261 ◽  
pp. 28-33
Author(s):  
Jun Zhang ◽  
Lu Cheng Ji ◽  
Bo Jin

Hydrogen energy has been considered as a clean alternative energy source substituting fossil fuels. Many countries consider it as the ultimate solution to the energy and environmental problems, even draw up the blueprint of “hydrogen economy” and heavily invest for research and development. However, after decades of research, the hydrogen energy technologies are still being prospective and explored, and haven’t been put into large scale production by now. This article begins with expatiation on the essence of hydrogen energy, makes analysis of various big challenges for hydrogen energy technologies, and reaches the conclusion that we should hold the rational and cautious attitude towards hydrogen energy source because the transition to hydrogen economy of unclear prospect must pay a very high cost, which is unbearable for the social and economic development status of developing countries.


Author(s):  
Yuting Luo ◽  
Zhiyuan Zhang ◽  
Fengning Yang ◽  
Jiong Li ◽  
Zhibo Liu ◽  
...  

Large-scale production of green hydrogen by electrochemical water splitting is considered as a promising technology to address critical energy challenges caused by the extensive use of fossil fuels. Although nonprecious...


Author(s):  
Reza Ziazi ◽  
Kasra Mohammadi ◽  
Navid Goudarzi

Hydrogen as a clean alternative energy carrier for the future is required to be produced through environmentally friendly approaches. Use of renewables such as wind energy for hydrogen production is an appealing way to securely sustain the worldwide trade energy systems. In this approach, wind turbines provide the electricity required for the electrolysis process to split the water into hydrogen and oxygen. The generated hydrogen can then be stored and utilized later for electricity generation via either a fuel cell or an internal combustion engine that turn a generator. In this study, techno-economic evaluation of hydrogen production by electrolysis using wind power investigated in a windy location, named Binaloud, located in north-east of Iran. Development of different large scale wind turbines with different rated capacity is evaluated in all selected locations. Moreover, different capacities of electrolytic for large scale hydrogen production is evaluated. Hydrogen production through wind energy can reduce the usage of unsustainable, financially unstable, and polluting fossil fuels that are becoming a major issue in large cities of Iran.


2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Hossein Alishah Aratboni ◽  
Nahid Rafiei ◽  
Raul Garcia-Granados ◽  
Abbas Alemzadeh ◽  
José Rubén Morones-Ramírez

Abstract The use of fossil fuels has been strongly related to critical problems currently affecting society, such as: global warming, global greenhouse effects and pollution. These problems have affected the homeostasis of living organisms worldwide at an alarming rate. Due to this, it is imperative to look for alternatives to the use of fossil fuels and one of the relevant substitutes are biofuels. There are different types of biofuels (categories and generations) that have been previously explored, but recently, the use of microalgae has been strongly considered for the production of biofuels since they present a series of advantages over other biofuel production sources: (a) they don’t need arable land to grow and therefore do not compete with food crops (like biofuels produced from corn, sugar cane and other plants) and; (b) they exhibit rapid biomass production containing high oil contents, at least 15 to 20 times higher than land based oleaginous crops. Hence, these unicellular photosynthetic microorganisms have received great attention from researches to use them in the large-scale production of biofuels. However, one disadvantage of using microalgae is the high economic cost due to the low-yields of lipid content in the microalgae biomass. Thus, development of different methods to enhance microalgae biomass, as well as lipid content in the microalgae cells, would lead to the development of a sustainable low-cost process to produce biofuels. Within the last 10 years, many studies have reported different methods and strategies to induce lipid production to obtain higher lipid accumulation in the biomass of microalgae cells; however, there is not a comprehensive review in the literature that highlights, compares and discusses these strategies. Here, we review these strategies which include modulating light intensity in cultures, controlling and varying CO2 levels and temperature, inducing nutrient starvation in the culture, the implementation of stress by incorporating heavy metal or inducing a high salinity condition, and the use of metabolic and genetic engineering techniques coupled with nanotechnology.


2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Vladan Mićić ◽  
Pero Dugić ◽  
Zoran Petrović ◽  
Milorad Tomić

The use of fossil fuels results in global warming and pollution. In comparison with fossil fuels biofuels represent an eco-friendly, biodegradable, sustainable, cost-competitive and promising alternative energy source. They contain high energy content and do not contribute to greenhouse effect. Therefore, using cheap or renewable resources as the feedstock for biofuels production has a great potential in terms of a major contribution to future energy supply. The production and use of biofuels is already well established and a further promotion of these fuels such as lipid biofuels (bioethanol, pure plant oils and biodiesel) and gas biofuels (biomethane, biohydrogen) mainly depends on non-technical issues, such as policies and cost–effectiveness. Biofuels will definitely stay for the foreseeable future and still can continue to provide the earth and the human population with a relatively clean source of energy with several benefits such as economic benefits of providing employment and health benefits of reduced carbon emissions, leading to cleaner air. With increasing sophistication of technology and intense research and development done, one can safely infer that biofuel will become more appealing and applicable for use on a globally commercial level. As such, biofuel is acknowledged as the Earth’s future energy source. Until a newer and cleaner energy source is discovered, scientists will definitely persist in researching and enhancing biofuels to make them more cost-effective, while still being environmentally friendly.


2021 ◽  
Vol 13 (16) ◽  
pp. 8873
Author(s):  
Minghao Chen ◽  
Yixuan Chen ◽  
Qingtao Zhang

Microalgae biofuel is expected to be an ideal alternative to fossil fuels to mitigate the effects of climate change and the energy crisis. However, the production process of microalgae biofuel is sometimes considered to be energy intensive and uneconomical, which limits its large-scale production. Several cultivation systems are used to acquire feedstock for microalgal biofuels production. The energy consumption of different cultivation systems is different, and the concentration of culture medium (microalgae cells contained in the unit volume of medium) and other properties of microalgae vary with the culture methods, which affects the energy consumption of subsequent processes. This review compared the energy consumption of different cultivation systems, including the open pond system, four types of closed photobioreactor (PBR) systems, and the hybrid cultivation system, and the energy consumption of the subsequent harvesting process. The biomass concentration and areal biomass production of every cultivation system were also analyzed. The results show that the flat-panel PBRs and the column PBRs are both preferred for large-scale biofuel production for high biomass productivity.


Author(s):  
Harry Audus ◽  
Paul Freund

In recent years, the possibility of climate change has begun to be considered seriously. Options available today can help reduce emissions at relatively little overall cost but may be able to achieve only moderate reductions. If it becomes necessary to reduce emissions further, it is likely there will be opportunities for new technologies as well as making greater use of existing ones. Bearing in mind the time required to develop and deploy new energy supply technologies on a large-scale, it is only sensible to adopt a precautionary stance. This requires better understanding of the potential of technologies not yet in widespread use and stimulation of the development and deployment of promising ones. The EEA Greenhouse Gas R&D Programme is working to improve understanding of technologies for reducing greenhouse gas emissions from fossil fuels. This is an example of effective co-operative action between different countries and industries. Membership is worldwide; through this work, members are able to learn about new technologies and share experiences. This paper reviews the work of the IEA Greenhouse Gas R&D Programme. The established options for reducing emissions include improving energy efficiency, substitution of lower-carbon fuels for high-carbon fuels, and introduction of alternative energy sources. If deep reductions in emissions are required, discussion tends to focus on alternatives to fossil fuels even though the latter provide a very large proportion of the energy used today. To avoid disruptive changes, the world will need to be able to continue using fossil fuels but in a climate-friendly way. Capture and storage of carbon dioxide could deliver deep reductions in emissions from fossil fuels but the technology is still in its infancy — this is the subject of on-going work by the IEA Greenhouse Gas R&D Programme. Enhancement of natural sinks, such as forests, could also help by sequestering atmospheric carbon dioxide. Use of biomass for power generation has also been examined to see how it compares as a large-scale mitigation option compared with capture and storage. Methane is another important greenhouse gas, produced by many human activities. Technology can help reduce emissions of methane; examples of some of these technologies will be described. The mechanism of Activities Implemented Jointly is potentially important for application of all of these options and the Greenhouse Gas Programme is working to improving understanding about viable options and methods of delivering successful projects.


First Monday ◽  
2005 ◽  
Author(s):  
Joshua Pearce

Although tremendous progress has been made in improving the conversion of sunlight into electricity with solar photovoltaic cells, their widespread adoption is primarily limited by high costs. This paper explores the use of the Internet as a catalyst for the diffusion of solar photovoltaic technology by reducing market risk. With market risk minimized by a database generated by a community of pledged consumers, solar cell companies would be motivated to construct a "Solar City Factory." Such a factory would produce solar panels that would enable systems costs to drop below US$1 per Watt and thus be less expensive than fossil fuels in providing bulk electricity. This price would have a positive–spiral effect encouraging many consumers to switch to solar electricity and transition the global energy infrastructure to renewable solar energy.


Author(s):  
Lian-Lian Liu ◽  
Fei Chen ◽  
Jing-Hang Wu ◽  
Wen-Wei Li ◽  
Jie-Jie Chen ◽  
...  

Graphitic carbon nitride (gCN) has attracted increasing interests in photocatalysis because of its visible-light-responsive ability, environmental friendliness, low cost and easiness of large-scale production. However, its practical application is restricted...


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