Biofuels from algae Research Papers (original) (raw)

The effects of different ferrous sulfate (FeSO4) concentrations on the fatty acid profile of the blue-green alga Arthrospira platensis cultured in Zarrouk’s medium to produce biodiesel were studied. Different ferrous sulfate concentrations (0, 0.005, 0.01, 0.05, and 0.1 g/L) and 0.01 g/L were examined on the biochemical composition of the alga and fatty acids profile of A. platensis. Findings revealed that the highest and lowest yields of fatty acid were 0 and 0.1 g/L FeSO4, respectively. It was also noticed an increase of palmitic acid, oleic acid, linoleic acid, γ-linolenic acid, and docosahexaenoic acid when ferrous sulfate was between 0.05 and 0.1 g/L, while these fatty acids decreased at low concentration. Ferrous sulfate at a concentration of 0.1 g/L exhibited an increase and best yields in the following: growth rate and the shortest doubling time, chlorophyll-a, phycocyanin, allophycocyanin, phycobiliproteins, and carotenoids. Thus, increasing the FeSO4 concentration to 0.1 g...

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- Chemistry, Biomass, Biodiesel, Biofuels from algae

50-day's free access https://authors.elsevier.com/a/1dnnLB8ccr0ST ........................................................................................................................................... Cyanobacteria are notorious for producing harmful algal blooms that present an ever-increasing serious threat to aquatic ecosystems worldwide, impacting the quality of drinking water and disrupting the recreational use of many water bodies. Remote sensing techniques for the detection and quantification of cyanobacterial blooms are required to monitor their initiation and spatiotemporal variability. In this study, we developed a novel semi-analytical approach to estimate the concentration of cyanobacteria-specific pigment phycocyanin (PC) and common phytoplankton pigment chlorophyll a (Chl a) from hyperspectral remote sensing data. The PC algorithm was derived from absorbance-concentration relationship, and the Chl a algorithm was devised based on a conceptual three-band structure model. The developed algorithms were applied to satellite imageries obtained by the Hyperspectral Imager for the Coastal Ocean (HICO™) sensor and tested in Lake Kinneret (Israel) during strong cyanobacterium Microcystis sp. bloom and out-of-bloom times. The sensitivity of the algorithms to errors was evaluated. The Chl a and PC concentrations were estimated with a mean absolute percentage difference (MAPD) of 16% and 28%, respectively. Sensitivity analysis shows that the influences of backscattering and other water constituents do not affect the estimation accuracy of PC (~2% MAPD). The reliable PC/Chl a ratios can be obtained at PC concentrations above 10 mg m−3. The computed PC/Chl a ratio depicts the contribution of cyanobacteria to the total phytoplankton biomass and permits investigating the role of ambient factors in the formation of a complex planktonic community. The novel algorithms have extensive practical applicability and should be suitable for the quantification of PC and Chl a in aquatic ecosystems using hyperspectral remote sensing data as well as data from future multispectral remote sensing satellites, if the respective bands are featured in the sensor.

- by Ilia Ostrovsky
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- Algorithms, Remote Sensing, Aquatic Ecology, Aquatic Toxicology

The current electricity demand of the Kingdom of Saudi Arabia (KSA) is around 55 GW, which is projected to reach up to 120 GW by 2032. This energy is mainly produced from fossil fuels, posing a serious risk to human health and environment. Moving towards a sustainable model, KSA government has initiated a plan called the King Abdullah City of Atomic and Renewable Energy (KACARE) to utilize the indigenous renewable energy resources to generate a further 54 GW energy from solar, wind, nuclear, geothermal and waste-to-energy (WTE). The arid nature of the KSA increases the importance of water in daily life and makes the country the third-largest per capita water user worldwide. About 12 thousand industries are working in different sectors, which produce large quantities of wastes and waste sludge on a daily basis. It has been estimated that 2.4 and 0.77 billion m3/ year of municipal and industrial wastewater respectively are produced in KSA, totaling to 3.17 billion m3/ year. Therefore, there is a huge potential of producing bioenergy and bioproducts, if this wastewater is treated in algae biorefinery. Algae as a ‘natural chemical factory’ has gained significant attention to produce several energy carriers, including starches for alcohols, lipids for diesel fuel, and bio-hydrogen (H2) for fuel cells and valuable materials and chemicals. Considerable progress has been made in recent years to optimize the production of energy and value-added products by utilizing algae under algae biorefinery concept. The biorefinery is a multi-process and multi-product system, similar to a petroleum refinery. It utilizes various feedstock to produce useful materials, chemicals, and bioenergy in the form of fuel, power, and heat in an integrated system. Algae contain natural oils, carbohydrates, and proteins for the production of biodiesel, ethanol, and H2. The leftover or residues of algae after oil extraction can be digested anaerobically to produce methane (CH4) as an energy carrier. Furthermore, the AD digestate can be a source of animal feed and organic fertilizer. Although, theoretically algae can produce various fuels, an array of valuable materials and capture carbon emissions, but in practice, profitable algal biofuel production has proven to be quite challenging. Most of these challenges lie in algae production methods, including a selection of suitable algae strain, its cultivation, harvesting, and extraction of value-added materials for energy and bioproducts along with their conversion pathways. The aim of this paper is to review the potential of algae biorefinery in KSA for the treatment of wastewater and production of bioenergy and bioproducts.

- by Dr. Abdul-Sattar Nizami and +1
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- Renewable Energy, Biomass, Energy, Biorefinery

A photobioreactor (PBR) is a closed system that utilizes a light source and nutrients under controlled environment to cultivate photosynthetically active microorganisms (Sudhakar, Premalatha et al. 2014, Khan, Shin et al. 2018, Rastogi, Pandey et al. 2018, Javed, Aslam et al. 2019). These microorganisms possess high potential of biomass energy which can be harvested and converted into biofuels using chemical conversion process. In general, phototrophic microorganisms can be produced in open or closed systems. The open system comprised of open pond or artificial raceway pond whereas closed system comprised of PBR systems under controlled environment (Fazal, Mushtaq et al. 2018, Rastogi, Pandey et al. 2018). The major advantage of closed PBR system over open system is that it helps to improve the quality and quantity of micro-algae by controlling invasion of other microorganism in the growth medium which thereby reduces downstream processing cost. A detail description of different types of PBR system can be found in many literatures (Marbelia, Bilad et al. 2014, Sudhakar, Premalatha et al. 2014, Wang, Stiles et al. 2014, Anderson, Katuwal et al. 2016, Katuwal 2017, Johnson, Katuwal et al. 2018, Rastogi, Pandey et al. 2018). This study presents the future scope and challenges associated with production of microalgae for biofuel production using PBR system and analyze the research gap in improving the existing system to enhance the potential of those PBR. Further, the focus of this study is to perform meta-analysis of harvest potential of existing PBR and quantify the quality and quantity of biofuels obtained from those systems. In the first part of the study, our approach will be extensively focused on reviewing current research studies conducted on PBR systems and their scales and various modifications introduced by different researchers to improve the performance of the PBR systems. In the second part of the study, our focus will on meta-analysis of input and output of different PBR

- by Ajay Sahah
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- Biofuels, PHOTOBIOREACTOR, Biofuels from algae, Design of photobioreactors

The biofuel industry is rapidly growing with a promising role in producing renewable energy and tackling climate change. Nanotechnology has tremendous potential to achieve cost-effective and process-efficient biofuel industry. Various nanomaterials have been developed with unique properties for enhanced biofuel production/utilization. The way forward is to develop nanotechnology-based biofuel systems at industrial scale.

- by Dr. Abdul-Sattar Nizami and +1
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- Environmental Engineering, Chemical Engineering, Biochemistry, Environmental Science

A crucial moment in the history of plankton research came during the 1920s with the introduction of the notion of biomass. Biomass links the 19th century aspirations elicited by plankton as the bottom of the food chain with the technocratic dreams of the perfect metabolic loop between aquatic mass and terrestrial needs of human beings during the 20th century. This article shows that the history of plankton research can be told as succession of historically bound epistemic hopes and societal utopia. It becomes evident that plankton as an individual organism is fragile yet simultaneously unchanging and able to resist most technical interventions and notions of optimization.

- by Ariane Tanner
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- History of Science, Biomass, Ecology, Algae

- by Dr. Abdul-Sattar Nizami and +1
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- Environmental Engineering, Chemical Engineering, Environmental Science, Energy Economics

Microalgae could be used to generate a number of environmentally friendly fuels, including oil (biodiesel), and ethanol with simultaneous consumption of CO2 from atmosphere. These microorganisms generate biofuels in photosynthetic reactions using water and sunlight as an energy source. The review briefly surveys data on production of biofuels (biodiesel and ethanol) and CO2 mitigation using microalgae available in literature. Different groups of algae described here with a view of their practical application for biofuel production. Particular attention in the review is given to mass cultivation of algae in open ponds and photobioreactors for biofuel generation and CO2 mitigation.

Biomass pyrolysis is a promising renewable sustainable source of fuels and petrochemical substitutes. It may help in compensating the progressive consumption of fossil-fuel reserves. The present article outlines biomass pyrolysis. Various types of biomass used for pyrolysis are encompassed, e.g., wood, agricultural residues, sewage. Categories of pyrolysis are outlined, e.g., flash, fast, and slow. Emphasis is laid on current and future trends in biomass pyrolysis, e.g., microwave pyrolysis, solar pyrolysis, plasma pyrolysis, hydrogen production via biomass pyrolysis, co-pyrolysis of biomass with synthetic polymers and sewage, selective preparation of high-valued chemicals, pyrolysis of exotic biomass (coffee grounds and cotton shells), comparison between algal and terrestrial biomass pyrolysis. Specific future prospects are investigated, e.g., preparation of supercapacitor biochar materials by one-pot one-step pyrolysis of biomass with other ingredients, and fabricating metallic catalysts embedded on biochar for removal of environmental contaminants. The authors predict that combining solar pyrolysis with hydrogen production would be the eco-friendliest and most energetically feasible process in the future. Since hydrogen is an ideal clean fuel, this process may share in limiting climate changes due to CO 2 emissions.
Keywords Sustainable and renewable energy source; Fossil-fuel alternatives; Biomass pyrolysis; Biofuel (bio-oil, biogas, biochar); Charcoal (activated carbon); Hydrogen fuel

- by Prof Dr Yehia Fahmy and +2
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- Environmental Engineering, Environmental Science, Development Economics, Environmental Economics

Throughout the past decade, municipal governments have steadily increased climate change adaptation measures, natural resource conservation programs, and clean energy initiatives. Through energy efficiency measures and renewable energy mandates, cities are poised to make significant impacts in the reduction of greenhouse gas emissions and the mitigation of climate risks in the clean energy transition. This Article addresses municipal directives of advanced biofuels as an integral part of the clean energy transition. Existing laws and policies have critical design flaws. Specifically, the Renewable Fuel Standard ("RFS") has proven to be burdensome and complex, producing more un-intended consequences than desired outcomes. Problems with the implementation of the RFS indicate that Congress

- by Nadia Ahmad
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- Renewable Energy, Biofuels, Biofuels from algae, Urban Energy
- by Sofía Rodríguez
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- Algae, Biofuels, Biofuels from algae

This article summarizes the potential of fresh water microalgae Acutodesmus dimorphus (A. dimorphus) for commercial scale cultivation. Recent studies on this alga are discussed. A recently concluded field trial of genetically modified strain of this alga, when cultivated outdoor in natural environment, demonstrated that the alga was able to express the modified phenotype with no observed adverse effect on native algal species in surrounding medium. Being first such US EPA approved evaluation of a genetically modified algae, this study has projected A. dimorphus as a promising GM alga that may now be taken up for industrial scale production. The article concludes by highlighting certain issues that need to be focused in order to make GM A. dimorphus a desirable strain for commercial scale cultivation.

- by Srishti Jha
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- Algae Culture, Algae Biotechnology, Algal Biofuels, Algal Biodiversity

The energy demand and waste generation have increased significantly in the developing world in the last few decades with rapid urbanization and population growth. The adequate treatment of the waste or sustainable waste management is essential not only from a sanitation point of view but also due to its economic and environmental values including its potential contribution to energy generation in the developing countries. Many of the developed nations have adopted the approach and strategies of the integrated waste management system (Figure 1) to maximize the waste-based revenues in the form of energy, fuels, heat, recyclables, value-added products, and chemicals along with more jobs and business opportunities. As a result, waste is no longer seen as refuse or discarded material, but an asset or resource to reduce not only the landfill volumes but also the dependency on fossil fuels by generating clean fuels.

- by Dr. Abdul-Sattar Nizami and +1
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- Renewable Energy, Wind Energy, Energy, Bioenergy

Microalgae biomass is suggested as a more sustainable feedstock for biofuel production than conventional biofuel crops. Algae biodiesel yields are likely to be between 3 and 30 times higher than 1st generation biofuel crops. Other advantages of algae cultivation are: no dependence on arable land, low nutrient losses and related emissions, possibility of using sea and waste water resources and the possibility of flue gas CO2 and NOx recycling. Cultivation depends on various aspects such as light, nutrient and carbon availability and competition with other species and is generally done in open ponds or closed bioreactors. Closed systems have higher yield due to better control and optimization but also have higher investment cost. Combination of both open and closed systems into a hybrid system is argued to have better overall feasibility. Several options exist for biological optimization of the process. This study confirms a high throughput method for fluorometric quantification of algae lipid content, which could possibly be used to increase lipid content by selective breeding. Moreover, it is shown that treated sewage waste water can be used directly for successful algae cultivation. Furthermore, an analysis of land, energy, water and CO2 requirements and emissions related to all major aspects of cultivation and biomass conversion suggest that net energy balance (NEB) ratios of 5.0 and 3.7 and 5.1 can be obtained for open, closed and hybrid systems respectively, which is slightly lower than ratios for sugarcane (7.0) and palm oil (7.9), but higher than those for corn (1.3) and soybean (1.9). The overall spatial energy gain, or spatial NEB, is as high as 56, 100 and 80 MJ m-2 y-1 for the 3 systems respectively which is considerably higher than any of the conventional biofuel crops. Fresh water requirements are
considerable (±0.9 m3/liter biodiesel) for open systems but this is still a factor 2-3 lower than irrigation water used for typical biofuel crops. Compared to fossil diesel combustion, reduction in
CO2 emissions were as high as 81% and 88% for open and closed systems respectively. Sensitivity analyses showed that modeled uncertainties had considerable impact on overall energy balances, but were within acceptable range, confirming the validity of the results.

- by Adam Posthuma
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- Environmental Science, Environmental Studies, Sustainable Development, Energy

Increasing greenhouse gases, ozone depletion, and continued decline of fossil fuel reserves have necessitated researchers to search for a low input, high output, non-palatable fuel crop which should not compete with food crops for agricultural land and water. The only organisms that come close enough to possess all the above characteristic features are microalgae. The unicellular green alga Chlorella vulgaris was isolated from local water bodies and maintained under controlled culture conditions. Algal biomass obtained by cultivating within bioreactor system was subjected to n-hexane soxhlet extraction which revealed 22.2% oil productivity. Molecular identification of the algal isolate was carried out through 18S rRNA sequencing employing ITS-1, ITS-4 universal primers, comparative analysis of amplification product revealed an overlapping region of 621 bp corresponding to 18S rRNA (Accession no. KX363808). Multiple sequence alignment of the amplified sequence using Nt-NCBI-BLAST revealed 92-94% sequence similarity to Chlorella Sp. USTB-01 The fatty acid composition was analysed using Perkin Elmer 500GC-MS which confirmed the presence of several FAME, thus evidencing its potential as an alternate fuel crop.

- by Nitin Wahi and +1
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- Algae Culture, Biofuels from algae, Algal Taxonomy and Algal Biotechnology

Prinsloo, G.J. 2011. Inlet Air Flow Meter for an Internal Combustion Engine. Bachelor Engineering Thesis, Mechatronic Engineering, Stellenbosch University, South Africa. doi 10.13140/2.1.3010.4649.
This project focus on the design an Inlet Air Flow Meter for accurate measurement of mass flow rate of atmospheric air into an engine during engine dynamometer tests. The meter will be used to determine the air-fuel ratio and volumetric efficiency of the engine. To determine if an Inlet Air Flow Meter can be designed and constructed to be sufficiently accurate for dynamometer applications, while evaluating the potential for commercial use in high performance engine management systems. The Inlet Air Flow Meter will be used to evaluate new Biofuel formulations and their performance in internal combustion engines, for example non-edible vegetable oils extracted for fatty acid compositions and biodiesel production, and to evaluate the air flow characteristics, engine performance and emissions production of non-edible oils.

- by Gerro Prinsloo
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- Engineering, Electrical Engineering, Mechanical Engineering, Robotics

The fact that algae biofuels introduce huge possibilities and a variety of options in dealing with the world‘s energy and climate problems is well documented in literature. With significant amounts of financial investments and effort being allocated to research, the race is now on to develop the first commercial-scale algal biofuel production infrastructure that is sustainable and commercially viable.
Most researchers readily concede that the commercial viability of algal biofuel economics are extremely challenging, highly variable, and subject to dynamic, speculative, and volatile commodity markets. The infrastructure required to develop a profitable, algae-based fuel generation is still in various stages of development and the final configuration is yet to be determined and demonstrated on an industrial scale.
A grounded theory and techno-economic framework for data analysis was adopted for the study. The comparative approach incorporated the use of case studies and addressed the research issue from various perspectives in chapters 3 and 4. An extensive review of current and relevant literature was carried out in Chapter 2. This was to provide the reader with a firm background of the opportunities and limitations peculiar to algae – biofuel production.
The analyses presented here will provide a deeper understanding of algae biofuel economic drivers and will help address the specific challenges of algae growth strains, harvesting and conversion technologies. More importantly, it sets the tone for a correct appraisal of algae biomass not only for fuel purposes but as part of a wider production chain that will add value to the other parts of the algae.
A remarkable change in fossil fuel production and consumption has been predicted based on the overall shift by key energy providers and governments towards clean fuel technologies. Microalgae production via the routes recommended in this dissertation will open up new ways for environment friendly manufacturing and nature preservation. It is possible to expect that in the near future the model recommendations will be better perceived, thus leading to global reorientation of priorities for algae biofuel development and deployment.

- by Ovo Adagha
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- Energy Economics, Renewable Energy, Marine Renewable Energy, Bioremediation

Addressing the contemporary waste management is seeing a shift towards energy production while managing waste sustainably. Consequently, waste treatment through gasification is slowly taking over the waste incineration with multiple benefits, including simultaneous waste management and energy production while reducing landfill volumes and displacing conventional fossil fuels. Only in the UK, there are around 14 commercial plants built to operate on gasification technology. These include fixed bed and fluidized bed gasification reactors. Ultra-clean tar free gasification of waste is now the best available technique and has experienced a significant shift from two-stage gasification and combustion towards a one-stage system for gasification and syngas cleaning. Nowadays in gasification sector, more companies are developing commercial plants with tar cracking and syngas cleaning. Moreover, gasification can be a practical scheme when applying ultra-clean syngas for a gas turbine with heat recovery by steam cycle for district heating and cooling (DHC) systems. This chapter aims to examine the recent trends in gasification-based waste-to-energy technologies. Furthermore, types of gasification technologies, their challenges and future perspectives in various applications are highlighted in detail.

- by Dr. Abdul-Sattar Nizami and +1
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- Environmental Engineering, Chemical Engineering, Environmental Science, Chemistry

Since early human history and existence energy rich plants, wood and forest cellulosic material have been used for fire, light, heating, cooking and other daily activities. Fossil energy was the foundation of our modern society and industrialization since last two centuries, while exploration and exploitation of oil reserves and petrochemistry have largely shaped 20th century. Increasing concerns on environmental pollution, accelerated global warming, and global climate changes, continuing world's crude oil (fossil fuels) consumption and depletion, as well as energy security and energy crisis caused by daily burning large amounts of fossil fuels, led to the attraction, search and development of renewable, carbon-neutral, economically viable alternative energy sources, such as biofuels, slowly displacing petroleum fuels. In continuously growing human population reaching about 10 billion in 2050, various renewable energy sources are promoted and developed, to ensure rising energy demands in a world running out of fossil energy sources. Biofuels are produced from any kind of available biomass and categorized based on utilized carbon resources into first-, second-and third-generation. Nevertheless, biofuels' future outlook is though beset by uncertainty. Hereby, various issues and concerns related to fossils and renewable biofuels are described and analyzed in present review article.

A B S T R A C T Pakistan has a strong potential of biodiesel production if the available feedstock resources are used sustainably and implementable policies are made in appropriate direction. To meet the energy demands and to find alternative and non-conventional resources of energy different challenges like research and development, infrastructure development, decentralized type of power delivery system, commercialization, market development , education and outreach programs, public awareness, monitoring, subsidies, government participation, technology transfer and evaluation must be considered and a comprehensive policy must also be made to systematically control and integrate them at national level. Pakistan is enriched with a wide variety of feed stocks which can be used for biodiesel production. Pakistan has an enormous potential of biodiesel production from jatropha, plants seed oil and microalgae which needs more consideration and practical applications. Harvesting the potential of microalgae for biodiesel production in Pakistan can be helpful to make it self-sufficient for energy demands. Pakistan is also facing several challenges like climate change, lack of financial resources, state of art technology and absence of appropriate government policies, which limit the commercialization of biodiesel. Although Government of Pakistan has established different institutions to promote and develop alternative energy technologies and to achieve 10% share of bioenergy in the energy sector by 2020, but still the targets are to be achieved on practical grounds. In this article, we have reviewed the potential of biodiesel in Pakistan, feed stocks, biodiesel production process, barriers and future developments. Future policies on biofuels, trends, recommendations, and the implication of existing policies are also discussed with research and developments goals for the promotion of biodiesel in Pakistan.

Background: Microalgae have been experimented as a potential feedstock for biofuel generation in current era owing to its’ rich energy content, inflated growth rate, inexpensive culture approaches, the notable capacity of CO2 fixation, and O2 addition to the environment. Currently, research is ongoing towards the advancement of microalgalbiofuel technologies. The nano-additive application has been appeared as a prominent innovation to meet this phenomenon.
Main text: The main objective of this study was to delineate the synergistic impact of microalgal biofuel integrated with nano-additive applications. Numerous nano-additives such as nano-fibres, nano-particles, nano-tubes, nanosheets, nano-droplets, and other nano-structures’ applications have been reviewed in this study to facilitate microalgae growth to biofuel utilization. The present paper was intended to comprehensively review the nano-particles preparing techniques for microalgae cultivation and harvesting, biofuel extraction, and application of microalgae-biofuel nano-particles blends. Prospects of solid nano-additives and nano-fluid applications in the future on microalgae
production, microalgae biomass conversion to biofuels as well as enhancement of biofuel combustion for revolutionary
advancement in biofuel technology have been demonstrated elaborately by this review. This study also highlighted the potential biofuels from microalgae, numerous technologies, and conversion processes. Along with that, the study recounted suitability of potential microalgae candidates with an integrated design generating value-added
co-products besides biofuel production.
Conclusions: Nano-additive applications at different stages from microalgae culture to end-product utilization presented strong possibility in mercantile approach as well as positive impact on the environment along with valuable co-products generation into the near future.

- by Gustavo Leite
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- Engineering, Biotechnology, Biomass, Microalgae
- by Dr. Abdul-Sattar Nizami and +1
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- Environmental Engineering, Chemical Engineering, Environmental Science, Energy Economics
- by Syarif Hidayatulloh
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- Algae Biotechnology, Biofuels from algae

The global demand for clean products obtained from biobased resources has increased significantly with the rapid growth of the world's population. In this context, microbially-produced compounds are highly attractive for their safety, reliability, being environment friendly and sustainability. Nevertheless, the cost of the carbon sources required for such approaches accounts for greater than 60% of the total expenses, which further limits the scaling up of industries. In recent years, algae have been used in numerous industrial areas because of their rapid growth rate, easy cultivation, ubiquity and survival in harsh conditions. Over the past decade, notable advances have been observed in the extraction of high-value compounds from algae biomass (ABs). However, few studies have investigated ABs as green substrates for microbial conversion into value-added products. This review presents the potential of ABs as the substrates for microbial growth to produce industrially-important products, which sheds light on the importance of the symbiotic relationship between ABs and microbial species. Moreover, the successful algal-bacterial gene transformation paves the way for accommodating green technology advancements. With the escalated need for natural pigments, biosurfactants, natural plastics and biofuels, ABs have been new resources for microbial biosynthesis of these value-added products, resolving the problem of high carbon consumption. In this review, the fermentative routes, process conditions, and accessibility of sugars are discussed, together with the related metabolic pathways and involved genes. To conclude, the full potential of ABs needs to be explored to support microbial green factories, producing novel bioactive compounds to meet global needs.

- by Mohammad Rehan and +1
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- Engineering, Chemical Engineering, Environmental Science, Chemistry

This paper details the analysis of biochemical methane potential (BMP) assessment of 83 substrates,
which may be deemed as: first generation substrates (food crops); second generation (grasses and
wastes); and third generation (seaweed). Significant variation in the BMP of a substrate may be found
depending on for example, season and method of harvest. This could lead to significant discrepancy
between energy production at the design stage and in operation of the facility. For example the BMP of
dairy slurry varied from 175 L CH4 kg1 VS in autumn (cattle fed on concentrate at end of farming year) to
239 L CH4 kg1 VS in the summer when cattle are fed fresh grass. Grass ranged from 156 (for hay) to
433 L CH4 kg1 VS for first cut baled silage. Saccharina latissima (brown seaweed) generated a higher BMP
36.4 m3 CH4 t1 than summer dairy slurry 16 m3 CH4 t1. In terms of a national resource, the cheapest
and most sustainable source of biomethane will be from wastes, but the resource is finite. Biomethane
from wastes could satisfy 18.4% of transport energy in Ireland. Larger resources will require third generation
substrates such as seaweed.

- by Eoin Allen
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- Biotechnology, Biogas, Cliamte Change, Biofuels from algae

Seaweed may be a source of third generation gaseous biofuel, in the form of biomethane. The scientific literature is sparse on the relative suitability of different varieties of seaweed to produce biomethane. This paper assesses the BMP (biochemical methane potential), ultimate analysis and theoretical yields of ten species of seaweed which may be found in commercial quantities around the coastline of Ireland. Saccharina latissima reported the highest BMP yield (ca. 342 L CH4 kg VS−1). S. latissima if farmed, may produce 10,250 m3 CH4 ha−1 yr−1 (365 GJ ha−1 yr−1) which is in excess of all land based liquid biofuel systems.

- by Eoin Allen and +1
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- Biogas, Marine Macro Algae, Biofuels from algae

Designers are expanding the definition of Ecological Design by incorporating biological processes and systems directly in their design. Systems like green roofs and living machines have proved themselves invaluable for reducing a design’s overall environmental footprint. Algae-based energy is almost 30 times less expensive per unit than energy generated by photovoltaic technology, and algae biodiesel can already be produced at market-competitive prices. With its efficient energy production and potential for improving the health of the surrounding air and water, algae cultivation is the next photosynthetically driven system primed for architectural integration.
This paper examines the various methods of algae farming, its opportunities to support cyclical systems, its design implications, and its integration into urban space. Cultivation methods range from low-tech open ponds to computer-automated bioreactors. Algae can effectively sequester carbon dioxide and treat wastewater while increasing its growth efficiency. These properties give it great potential for integration with other infrastructural systems like wastewater systems. These synergies can be developed into closed-loop systems within the built environment, resulting in lower CO2 emissions, nutrient reuse, and efficient energy generation. These multi-layered benefits of algae cultivation initiate a rethinking of the relationships between sunlight, alternative energy and material recycling. This paper argues these relationships have strong potential for the future development of algae-integrated systems. Possibilities include integration into urban landscapes, existing building stock and power generation on the neighborhood scale. Challenges include economically down-scaling algal systems, onsite harvesting and the logistics of combining new infrastructures. Algae’s high ecological performance generates a multi-fold contribution towards improving the health of the environment. With its combination of carbon neutral/negative energy production and ecological recycling of environmental pollutants, the integration of algae cultivation in the built environment opens a new dimension to ecological design.

- by Gundula Proksch
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- Architecture, Built Environment, Algae, Algae Culture

The idea to develop biofuels from algae is not a new one, but prior to 21st century
algal proponents did not gain enough fame. However, since 2007 there has been a significant
increase of interest in algal biofuels and the prospects of their application in the future has been
greatly overhyped. This review deals with different kinds of biofuels – biodiesel, bioethanol,
hydrocarbons, biogas and whether algae can be applied in their production. Our conclusion is
that while there is some advancement in growing algae and processing of biomass, harnessing
biofuels from them is still a daunting task and far from the promised green future.

This article presents a summary of the main findings from a collaborative research project between Aalto University in Finland and partner universities. A comparative process synthesis, modelling and thermal assessment was conducted for the production of Bio-synthetic natural gas (SNG) and hydrogen from supercritical water refining of a lipid extracted algae feedstock integrated with onsite heat and power generation. The developed reactor models for product gas composition, yield and thermal demand were validated and showed conformity with reported experimental results, and the balance of plant units were designed based on established technologies or state-of-the-art pilot operations. The poly-generative cases illustrated the thermo-chemical constraints and design trade-offs presented by key process parameters such as plant organic throughput, supercritical water refining temperature, nature of desirable coproducts, downstream indirect production and heat recovery scenarios. The evaluated cases favoring hydrogen production at 5 wt. % solid content and 600 • C conversion temperature allowed higher gross syngas and CHP production. However, mainly due to the higher utility demands the net syngas production remained lower compared to the cases favoring BioSNG production. The latter case, at 450 • C reactor temperature, 18 wt. % solid content and presence of downstream indirect production recorded 66.5%, 66.2% and 57.2% energetic, fuel-equivalent and exergetic efficiencies respectively.

- by Mohamed Magdeldin and +2
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- Hydrogen, Biofuels from algae, Polygeneration, Supercritical water gasification (SCWG)
- by Arnaud Helias and +1
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- Biofuels from algae
- by Wiebke Boeing and +1
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- Biological invasions, Microalgae, Lipids, Biofuel and Bio Ethanol Production from Biomass

s The cyanobacterium Spirulina platensis is quite spread all over the world due to its high nutritional value. It has been used as a protein source and vitamin supplement in healthy diet, in aquaculture and fisheries. Cyanobacterium Spirulina is capable to grow in various kinds of culture media. Furthermore, decomposed organic and inorganic nutrients media have been proven to be a good source of culture medium for Spirulina by many researchers. In this work, S. platensis was cultivated using dry vermicompost from fish sludge (VCFS) or cow manure (VCCM). 100 g of dry vermicompost from each source (VCFS / VCCM) collected and compared with Aiba and Ogawa liquid medium which was used as a culture medium. The results obtained showed that the highest protein and "chlorophyll a" ratio of S. platensis were observed in the biomass harvested from T2 (VCCM) and T3 (Aiba and Ogawa liquid medium). The highest dried S. platensis biomass was harvested from T2 (VCCM) while the lowest came from T1 (VCFS). The chemical composition (as % of dry weight) revealed that (VCCM) was higher in total phosphorus, total nitrogen and organic matter than (VCFS). Keywords: Spirulina platensis, vermicompost. INTRODUCTION The quality of aquaculture waste materials are highly variable source of metabolic products and food wastes (Beveridge et al. 1992). Solid wastes represent a significant proportion of the applied feed. Schuenhoff et al., (2003) showed that more than 80 % of the feed nitrogen content and more than 75 % of the phosphorus content are excreted in the water in both dissolved and particulate forms. Compost made from fish manure (sludge) Egyptian Journal for Aquaculture

- by reham abdelhay
- •
- Algae Culture, Harmful Algal Blooms (Biology), Green Algae, Biofuels from algae

Biogas potential was explored for animal manure, wheat straw, food waste and rice straw. Batch experiments were performed at a laboratory scale using potential biomethane assays (BMP) for a period of 50 days. The biogas yield was observed higher when using rice straw (0.40 m3/kg VSadded) as a substrate, as compared to wheat straw (0.33 m3/kg VSadded) and animal manure (0.30 m3/kg VSadded) substrates. Around 10% of biogas was produced in the initial phase of 4 days for manure, wheat straw, and rice straw feedstocks. During the middle phase of 30 days for these feedstocks, 65 – 80% of biogas was produced. Less than 20% of biogas was produced during the final phase of last 16 days of the experiment. The biogas production from food waste was found lowest (0.02 m3/kg VSadded) among all substrates. Therefore, the anaerobic digestion (AD) of both food waste and animal manure is more suited in co-digestion fashion than mono-digestion.

- by Dr. Abdul-Sattar Nizami and +1
- •
- Environmental Engineering, Bioengineering, Chemical Engineering, Environmental Science
- by Dr. Rameshprabu Ramaraj
- •
- Algae Culture, Algae Biotechnology, Biofuels from algae, Algae biomass

In this paper we investigate approaches that could potentially reduce dependence on fossil fuels and mitigate greenhouse gas emissions (GHGs), using existing or growing technologies, for the time-line leading up to 2050. We use a baseline prediction of anticipated emissions up to 2050. To calculate potential emissions reductions, three high energy demand sectors in Canada – transport, heating and electricity – are analyzed. We propose the following mitigation scenarios in each sector: using a 50% algae biofuel blend ratio (AB50) in road and railway transport fuels, applying solar thermal systems for heating in buildings, deploying solar photovoltaic for large-scale electricity generation, and operating hybrid wind-PV’s for mini-grid systems in remote communities. We project that these approaches are feasible within the framework of 40 years.

- by Ovo Adagha
- •
- Renewable Energy, Solar thermal, Algae, Solar PV Systems Installation

BACKGROUND: A major bottleneck in microalgal biodiesel production is lipid content, which is often low in microalgal
species. The present study examines Chlorella vulgaris as a potential feedstock for biodiesel by identifying and evaluating the
relationships between the critical variables that enhance the lipid yield, and characterizes the biodiesel produced for various
properties.
RESULTS: Factors affecting lipid accumulation in a green microalga, Chlorella vulgaris were examined. Multifactor optimization
raised the lipid pool to55%dry cell weight against9%control.WhenC. vulgaris cells pre-grown in glucose (0.7%)-supplemented
medium were transferred to the optimized condition at the second stage, the lipid yield was boosted to 1974 mg L−1, a value
almost 20-fold higher than for the control. The transesterified C. vulgaris oil showed the presence of∼82% saturated fatty acids,
with palmitate and stearate as major components, thus highlighting the oxidative stability of C. vulgaris biodiesel. The fuel
properties (density, viscosity, acid value, iodine value, calorific value, cetane index, ash and water contents) are comparable
with the international (ASTM and EN) and Indian (IS) biodiesel standards.
CONCLUSION: C. vulgaris biomass with 55% lipid content and adequate fuel properties is potentially a renewable feedstock for
biodiesel.

- by MOUMITA BISHAI
- •
- Algal Biofuels, Biofuels from algae, Algal Biodiesel Production, Algal Biodiesel
- by Faizal Bux
- •
- Environmental Engineering, Mechanical Engineering, Chemical Engineering, Microwave

District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand – outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations. Abstract The concept of energy from waste is getting popular nowadays across the globe, as being capable of producing multi fuels and value-added products from different fractions of municipal solid waste (MSW). The energy recovery technologies under this concept are anaerobic digestion (AD), pyrolysis, transesterification, refuse derived fuel (RDF) and incineration. This concept is very relevant to implementation in countries like Saudi Arabia, who wants to cut their dependence on oil. Moreover, the waste to energy becomes the imperative need of the time because of new governmental policy 'Vision 2030' that firmly said to produce renewable energy from indigenous sources of waste, wind and solar and due to given situations of Hajj and Umrah with massive amounts of waste generation in a short period. This study focused on two waste to energy technologies, AD and pyrolysis for food (40% of MSW) and plastic (20% of MSW) waste streams respectively. The energy potential of 1409.63 and 5619.80 TJ can be produced if all of the food and plastic waste of the Madinah city are processed through AD and pyrolysis respectively. This is equivalent to 15.64 and 58.81 MW from biogas and pyrolytic oil respectively or total 74.45 MW of continuous electricity supply in Madinah city throughout the whole year. It has been estimated that the development of AD and pyrolysis technologies will also benefit the economy with net savings of around US 63.51andUS63.51 and US 63.51andUS53.45 million respectively, totaling to an annual benefit of US 116.96million.Therefore,inSaudiArabiaandparticularlyinHoliestcitiesofMakkahandMadinahthebenefitsofwastetoenergyareseveral,includingthedevelopmentofrenewable−energy,solvingMSWproblems,newbusinesses,andjobcreationandimprovingenvironmentalandpublichealth.AbstractTheconceptofenergyfromwasteisgettingpopularnowadaysacrosstheglobe,asbeingcapableofproducingmultifuelsandvalue−addedproductsfromdifferentfractionsofmunicipalsolidwaste(MSW).Theenergyrecoverytechnologiesunderthisconceptareanaerobicdigestion(AD),pyrolysis,transesterification,refusederivedfuel(RDF)andincineration.ThisconceptisveryrelevanttoimplementationincountrieslikeSaudiArabia,whowantstocuttheirdependenceonoil.Moreover,thewastetoenergybecomestheimperativeneedofthetimebecauseofnewgovernmentalpolicy′Vision2030′thatfirmlysaidtoproducerenewableenergyfromindigenoussourcesofwaste,windandsolarandduetogivensituationsofHajjandUmrahwithmassiveamountsofwastegenerationinashortperiod.Thisstudyfocusedontwowastetoenergytechnologies,ADandpyrolysisforfood(40116.96 million. Therefore, in Saudi Arabia and particularly in Holiest cities of Makkah and Madinah the benefits of waste to energy are several, including the development of renewable-energy, solving MSW problems, new businesses, and job creation and improving environmental and public health. Abstract The concept of energy from waste is getting popular nowadays across the globe, as being capable of producing multi fuels and value-added products from different fractions of municipal solid waste (MSW). The energy recovery technologies under this concept are anaerobic digestion (AD), pyrolysis, transesterification, refuse derived fuel (RDF) and incineration. This concept is very relevant to implementation in countries like Saudi Arabia, who wants to cut their dependence on oil. Moreover, the waste to energy becomes the imperative need of the time because of new governmental policy 'Vision 2030' that firmly said to produce renewable energy from indigenous sources of waste, wind and solar and due to given situations of Hajj and Umrah with massive amounts of waste generation in a short period. This study focused on two waste to energy technologies, AD and pyrolysis for food (40% of MSW) and plastic (20% of MSW) waste streams respectively. The energy potential of 1409.63 and 5619.80 TJ can be produced if all of the food and plastic waste of the Madinah city are processed through AD and pyrolysis respectively. This is equivalent to 15.64 and 58.81 MW from biogas and pyrolytic oil respectively or total 74.45 MW of continuous electricity supply in Madinah city throughout the whole year. It has been estimated that the development of AD and pyrolysis technologies will also benefit the economy with net savings of around US 116.96million.Therefore,inSaudiArabiaandparticularlyinHoliestcitiesofMakkahandMadinahthebenefitsofwastetoenergyareseveral,includingthedevelopmentofrenewable−energy,solvingMSWproblems,newbusinesses,andjobcreationandimprovingenvironmentalandpublichealth.AbstractTheconceptofenergyfromwasteisgettingpopularnowadaysacrosstheglobe,asbeingcapableofproducingmultifuelsandvalue−addedproductsfromdifferentfractionsofmunicipalsolidwaste(MSW).Theenergyrecoverytechnologiesunderthisconceptareanaerobicdigestion(AD),pyrolysis,transesterification,refusederivedfuel(RDF)andincineration.ThisconceptisveryrelevanttoimplementationincountrieslikeSaudiArabia,whowantstocuttheirdependenceonoil.Moreover,thewastetoenergybecomestheimperativeneedofthetimebecauseofnewgovernmentalpolicy′Vision2030′thatfirmlysaidtoproducerenewableenergyfromindigenoussourcesofwaste,windandsolarandduetogivensituationsofHajjandUmrahwithmassiveamountsofwastegenerationinashortperiod.Thisstudyfocusedontwowastetoenergytechnologies,ADandpyrolysisforfood(4063.51 and US 53.45millionrespectively,totalingtoanannualbenefitofUS53.45 million respectively, totaling to an annual benefit of US 53.45millionrespectively,totalingtoanannualbenefitofUS116.96 million. Therefore, in Saudi Arabia and particularly in Holiest cities of Makkah and Madinah the benefits of waste to energy are several, including the development of renewable-energy, solving MSW problems, new businesses, and job creation and improving environmental and public health.

A sustainable transition is premised upon moving from a carbon energy regime to a renewable energy regime; a highly contested political-economic transformation, to say the least. In places like the United States and European Union the main form of renewable energy is bioenergy, especially biofuels. Recent policy and industry efforts are focusing on the development and implementation of what are known as ‘drop-in’ biofuels, so named because they can be incorporated into existing distribution infrastructure (e.g. pipelines) and conversion devices with relatively few, if any, technical modifications. As with carbon energy, bioenergy has particular materialities that are implicated in the political-economic possibilities and constraints facing societies around the world. These political materialities of bioenergy shape and are shaped by new energy regimes and therefore problematize the notion of a drop-in biofuel. Thus further examination of the political materialities of bioenergy, and of renewable energy more generally, is of critical importance for successful sustainable transitions.

- by Kean Birch and +1
- •
- Geography, Human Geography, Social Geography, Environmental Geography

The non-edible oil from Schleichera oleosa possesses the potential as a feedstock for biodiesel production.
In this study, the biodiesel production was performed using two-step transesteriﬁcation process on a lab-
oratory scale. The parameters studied were reaction temperature, molar ratio of methanol to oil, catalyst
concentration, reaction time and catalysts type. An analysis of variance (ANOVA) was used to determine
the methyl ester yield. The optimum conditions were obtained as follows: reaction temperature at 55 C,
methanol to oil molar ratio of 8:1, 1 wt.% of hydroxide catalyst (KOH and NaOH) and 1 wt.% methoxide
catalyst (CH3OK and CH3ONa) for reaction time 90 min. Based from these optimum conditions, the
observed ester yields from different catalysts were average 96%, 93%, 91% and 88% for KOH, NaOH,
CH3OK and CH3ONa respectively as the catalyst. S. oleosa methyl ester (SOME) exhibited a satisfying
oxidative stability of 7.23 h and high cetane number (50.6) compared to petrol diesel (49.7). Besides,
SOME has good pour and cloud point of 3.0 C and 1.0 C respectively due to high unsaturated fatty
chain. As a conclusion, this study reveals that biodiesel production from SOME, as one of non-edible feed-
stock, is able to be an alternative for petrol diesel. Moreover, the produced biodiesel from SOME could be
used in diesel engine without major modiﬁcation due to its properties and can be used in cold regions.

- by Hwai Chyuan Ong and +5
- •
- Biodiesel Production, Biofuels from algae, Bioethanol Production

Among the most pressing energy and environmental strategic challenges today is to identify and deploy viable alternatives to fossil-fuel-based energy systems The barriers to deployment are systematic, leading to a state of affairs described as ‘carbon lock-in’ (Unruh
2000; Neuhoff 2007). Simply stated, even if alternative energy systems are cost-competitive in theory, the prime movers that control their diffusion throughout society –
for example, conversion and distribution infrastructure; financing mechanisms; skilled labour force; attitudes toward particular kinds of energy production activities and energy services – exhibit a preference for incumbent carbon-intensive fossil energy resources. Carbon lock-in represents path dependencies within energy systems including sunk-cost in prevailing infrastructure and entrenched political interests along with positively reinforcing relationships with broader system dynamics, from global financial logics that continue to monetise unburned carbon through energy
futures contracts to our everyday practices and expectations about mobility, comfort, and overall
well-being that underpin regular visits to the gasoline station. All of this is to say that energy systems are sociotechnical in nature, characterised by deep and often subtle interdependencies between technological, social, political-economic, and cultural processes which operate across the energy supply chain and at all scales of energy system operation (Miller, Richter, and O’Leary 2015).

- by Kean Birch
- •
- Bioengineering, Geography, Human Geography, Political Geography and Geopolitics

The Energy Policy Act is a bill passed by Congress, and signed into law by President George W.Bush in 2005 which established a bioethanol target in order to offset U.S. dependence on foreign oil. Since then, many different perspectives have contributed to the wealth of data available in regards to bioethanol production from agriculture; responses which have substantiated and criticized almost every step of each process. Two challenges have come to the forefront of the confusing mess of information: 1) challenge for the best energy return on investment [investmentis used here to encompass time, resource, energy, and monetary costs] and 2) challenge for the maximum net greenhouse gas reduction.In 2005, Perlack et al. of the Oak Ridge National Laboratories (ORNL) in cooperation with the Department of Energy (DoE) released the first Billion Ton Study included findings about the feasibility of the government’s proposed bioethanol targets. The report failed to include costs notrelated to the economic scheme of money and resource-related statistics. Since then, seriousquestions have arisen as a result of the ‘push’ to use food for fuel; ethical questions regarding starving and under-represented populations, criticisms regarding the true reductions of emissions, and questions about scalability. My investigation hopes to have covered some of the environmental considerations in the process of finding a better feedstock for the production of bioethanol in the U.S.

- by Vivian W Cheng
- •
- Algae, Cellulosic Ethanol, Biofuels, Algal Biofuels

This study was conducted to find out the Relationships between Nutrients and Chlorophyll a concentration
in the International Alma Gol Wetland. Water samples were collected fortnightly from five stations in the wetland.
They were collected during summer and autumn. Results illustrated that there was a significant correlation between
chlorophyll a and logarithm chlorophyll a with nitrate, nitrite (P<0.01) and ammonia (P<0.05) but there was no significant
correlation between chlorophyll a and logarithm chlorophyll a with silica, total alkalinity, sulfate and resolve
phosphorus (P>0.05).

- by Hamide Kordi
- •
- Algae Culture, Algae Biotechnology, ORNAMENTAL FISH AQUACULTURE, Biofuels from algae

Biofuels industry is dealing with generation of renewable fuels from organisms or by organisms. The major products of this industry are ethanol, biodiesel and biogas. At present time, biofuels are made mainly from plant material such as corn, sugarcane, or rapeseed. Thus, biofuels industry depends heavily on agriculture. Biofuels are excellent transportation fuels that are used as gasoline and diesel substitute. Biofuels can also be burned in electrical generators to produce electricity. Biofuels are considered by many as a future substitute for fossil fuels such as coal, oil/petroleum, or natural gas.

- by Sergei A Markov
- •
- Biofuels, Algal Biofuels, Biofuels from algae, Biofuel Industry

- by Dr. Abdul-Sattar Nizami and +1
- •
- Environmental Engineering, Chemical Engineering, Environmental Science, Energy Economics