Renewable Energy Global Innovations features: Increased short-circuit current density and external quantum efficiency of silicon and dye sensitised solar cells through plasmonic luminescent down-shifting layers

Significance Statement

Luminescent down-shifting is an optical approach to increase photovoltaic device efficiency and it consists of luminescent species such as quantum dots, organic dies and rare-earth complexes doped in a transport polymer sheet and deposited on top of photovoltaic cells.

Spraying of luminescent species on top of photovoltaic cells either by spray coating or incorporation into a multifunctional coating system based on photo-curable fluoropolymer have shown significant improvement in power conversion efficiency of uncoated dye sensitized solar cells devices thereby improving cell stability and prevention of photochemical and physical degradation.

In a recent article by Ahmed et al. (2016) and published in Solar Energy, investigations were made on plasmonic luminescent down-shifting (pLDS) layers applied to silicon cells (c-Si) and dye sensitized solar cells (DSSC) solar cells.

Quantum dots exhibits broad absorption spectra, high absorption coefficients and emission wavelength which can be tuned according to their size as a result of quantum confinement having advantages over organic dies due to their higher brightness and stability. However, the luminescent down-shifting suffer from self-absorption; a case where downshifted photons are reabsorbed by quantum dots or dye within the downshifting layer. Optical properties of luminescent species according to research were shown to exhibit dramatic emission enhancement in presence of metal nanoparticles on quantum dots ion dye emitters.

For the experiments, core-shell type Cadmium Selenide/Zinc Sulfide (CdSe/ZnS) quantum dots were used as fluorescent material which has a quantum yield of 0.7±0.07 measured in solution. Silver nanoparticles were used in plasmonic luminescent down-shifting composite layer and preparation of fluorescent species with silver nanoparticles composite layers followed.

The performance of c-Si and DSSC solar cells encapsulated with quantum dots luminescent down-shifting layer and plasmonic-quantum dots luminescent down-shifting composite layer was compared.

Absorption and emission measurement of quantum dots with/without silver nanoparticles revealed significant increase in emission for the plasmonic luminescent down-shifting layer when compared to layer with no silver nanoparticles. This result shows enhancement attributed to silver nanoparticles exhibiting strong scattering of incident light which greatly enhances local electric fields at surface plasmon resonance frequency.

Current-voltage curves for c-Si and DSSC solar cells showed electrical characterization increase of 1.92% in current density due to presence of quantum dots when compared to bare c-Si cells. Enhancement of 7.84% was calculated for plasmonic-quantum dots luminescent down shifting composite layer. There was also 5.81% increase in current density for plasmonic-quantum dots luminescent down shifting composite layer when compared with quantum dots luminescent down shifting layer.

Electrical characterization of DSSC solar cells showed a decrease of 8.03% in current density of quantum dots luminescent down shifting when compared to bare DSSC solar cells while enhancement of 3.31% was calculated for plasmonic-quantum dots luminescent down-shifting composite layer. There was also 11.29% increase in current density for plasmonic-quantum dots luminescent down shifting composite layer when compared with quantum dots luminescent down shifting layer.

External quantum efficiency of bare c-Si solar cells was poor reaching only 11% at wavelength below 400nm. Improvement of external quantum efficiency at the same wavelength for quantum dots luminescent down-shifting layer and plasmonic-quantum dots luminescent down-shifting layer were 23% and 52%, respectively. The high improvement in plasmonic-quantum dots luminescent down-shifting layer can be attributed to presence of silver nanoparticles in its composite layer.

The external quantum efficiency of DSSC solar cells had overall decrease between 300-800 nm for quantum dots luminescent downshifting layer. However, plasmonic-quantum dots composite layer show 3.03% increase when compared to DSSC bare solar cell and 11.71% when compared to quantum dots luminescent down-shifting device. Significant increase was calculated between 300 and 500nm where current density J_sc reached 21.64% and 5.16% for plasmonic-quantum dots composite layers compared to bare DSSC solar cell and quantum dots luminescent down-shifting device, respectively.

 CdSe/ZnS quantum dots investigations in Ahmed et al. (2016) studies has the ability to absorb light below 465nm and emits at 500nm flows shifting the optical wavelength of the cell from poor optical response (short wavelengths) to external quantum efficiency (at longer wavelengths).

The research team for the first time demonstrated plasmonic luminescent down-shifting current density J_sc reaching up to 22% increase in region of 300-500nm for c-Si and DSSC solar cells.

About The Author

Dr. Hind Ahmed is a graduate of the prestigious Graduate Studies Program at the Singularity University, NASA AMES, California, USA. She has a strong background in Mathematics, Physics and Engineering with the focus in the area of solar energy research. She holds an Honour’s degree in Physics, a Postgraduate Diploma in Mathematical Sciences, a Master degree in Material Physics, a Professional Master in Micro/Nano Electromechanical System and a PhD in Physics.

She is currently working as post-doctoral researcher in the Solar Energy Applications group in Trinity College Dublin under ERC Starter grant (PEDAL) which involves the design, development, characterization and fabrication of large scale plasmonic luminescent down shifting devices for enhancing the efficiency of solar cells. 

About The Author

Dr. John Doran

Affiliation: School of Physics, Dublin Institute of Technology (DIT), Ireland

Professional Appointments:

Head of School, School of Physics, DIT: 2009-present

Assistant Head of School, School of Physics, DIT: 2003 – 2009

Lecturer, School of Physics, DIT: 1996 – 2003

Postdoctoral Research Fellow, School of Physics, TCD, 1994 – 1996.

Education: BA(Mod) Experimental Physics, 1989, Trinity College Dublin

PhD, 1994, Trinity College Dublin – Thesis Title: Exciton Dynamics in CdZnTe/ZnTe Multiple Quantum Wells.

Research and Professional Experience:

Solar Energy Group within the Dublin Energy Lab. Research involves two aspects: 1. Design, fabrication, optical and electrical characterisation, and modelling of Luminescent Solar Concentrators (LSCs) and Luminescent Downshifting (LDS) devices incorporating plasmonic effects.

Applications of switchable mirror technology to solar energy. Recent research has focused on the novel incorporation of metal nanoparticles into LSC and LDS devices in order to enhance optical emission and overcome losses inherent in these devices. This novel plasmonic approach has been demonstrated experimentally and device performance has been modelled successfully using a ray-tracing approach. 

About The Author

Dr Sarah McCormack is an Associate Professor and lead PI in the Solar Energy Applications group in Trinity College Dublin. She has been working in the area of solar energy research for over 15 years. She has published over 90 publications in the areas of solar energy and energy storage and has over 1000 citations. She has supervised 11 PhD students to completion and is currently supervising a further 6 along with 4 Post doctoral researchers. She has been awarded funding of over 3M in national and EU funded projects. She is the Irish representative on European PV Technology Platform Mirror Group nominated by the Sustainable Energy Authority of Ireland, a member of the Renewable Heating and Cooling Platform, Secretary of the Solar Energy Society of Ireland. Recently she has been awarded a prestigious ERC Starter grant (PEDAL) to continue her work in LS devices for enhancing the efficiency of solar cells. 

Journal Reference

Ahmed H¹, Doran J², McCormack S¹. Increased Short-Circuit Current Density and External Quantum Efficiency of Silicon and Dye-Sensitized Solar Cells through Plasmonic Luminescent Down-Shifting Layers.  Solar Energy, Volume 126, 2016, Pages 146–155.

Show Affiliations

1. School of Engineering, Trinity College Dublin, Dublin, Ireland
2. Dublin Energy Lab, Dublin Institute of Technology, Dublin, Ireland

 

 

Go To Solar Energy

 

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Floating offshore wind turbines: designing against the forces of nature

Significance Statement

Studies done before on a small scale floating horizontal axis wind turbine in surge motion showed thatthere is an increasing amplitude of the cyclic thrust and power generation against tip speed ratio. A numerical study using an Actuator Disk (AD) Navier Strokes model, a Blade Element Momentum (BEM) model and a Generalized Dynamic Wake (GDW) model was performed in order to determine the previous observations on the full-scale NREL 5MW reference rotor in surge motion. The research question was to understand the reason why such high variations in thrust and torque occur at non-optimal tip speed ratios. The research was done to improve the understanding of the fundamental science governing floating offshore machines so as to make them commercially viable in the future.

The test was performed by maintaining the surge amplitude and surge frequency fixed and changing the tip speed ratio. Full details of the AD model can be found in the full paper. Results are then compared with BEM combined with dynamic inflow engineering models as well as the GDW model.

When the operating tip speed is increased the released vorticity in the wake becomes stronger causing an increase in the amplitude variations of the flow inductions in the axial, radial and swirl directions. The extent of the radial expansion and contraction of the wake was found to increase with increasing tip speed ratio. The study makes us conclude that the dynamic wake model can be adopted for BEM modeling of a surging rotor but only if mean quantities are of interest. The GDW model on the other hand gives quite an acceptable agreement with what the AD model.

Their work give credit to the previous experiments conducted on a small model rotor. They produce similar results that thrust and power amplitudes vary with wave amplitude and frequency. The unsteady variations in thrust and power are clearly observedto increase at higher tip speed ratios related to turbulent wake condition. This affects the structural and electrical design of the commercial turbines to manage fatigue when the turbine is operated in its rated conditions. The power will have to be tapped by suitable electronics that can handle the strength and instability from the turbine. The study recommends that it is ideal to operate at low speed tip ratios to reduce the fatigue loads on the blades, especially where the power demands are not very high. Concludingly, the results from this quantitative study were compared to the FAST code results using both BEM and unsteady GDW models.. Some difference was found at high tip speed ratio towards the onset of the turbulent wake state. The results for low tip speed ratios agreed quite well. The study was however limited due to the fact that the rotor was tested under fixed surge conditions and varying tip speed ratios. 

 

About The Author

Dr. Daniel Micallef is an academic at the University of Malta where he joined the Environmental Design department of the Faculty for the Built Environment in September 2014.

Dr. Micallef graduated in Mechanical Engineering from the University of Malta in 2008 with first class honours. He started his professional career in the public sector with the Malta Resources Authority as an energy analyst. During this time he started pursuing a career in academia. He read for a joint PhD with the Delft University of Technology in the Netherlands (where he formed part of the DUWIND wind energy research group) and the University of Malta.

His research focused on furthering the understanding of wind turbine flow phenomena close to the tip. He was awarded his PhD in 2012. During the final year of his PhD, Dr. Micallef also worked as a project officer at the Mechanical Engineering Department of the University of Malta where he developed analysis tools and contributed in the design of an urban wind turbine being developed by industry. His research career took a twist in 2012 were he continued his research experience as a post-doctoral researcher on the HILDA FP7 project. While continuing to publish his work in wind energy, his post-doc research focused on a different topic – modelling of friction stir welding of steels.

He developed finite element and computational fluid dynamics models for the numerical analysis of the process. During his final months on the project, he was engaged as a lecturer at the Malta College of Arts Science and Technology (MCAST). His experience as a post-doc researcher and MCAST lecturer ended in September 2014.

Dr. Micallef published in high quality peer reviewed journals and conferences worldwide. His current major interests are in the fields of wind energy, wind engineering and building physics. Apart from his research activities, he lectures in undergraduate and Masters courses. Dr. Micallef is currently the secretary general of the Chamber of Engineers (an NGO). He is also the COST (Cooperation in Science and Technology) representative of Malta in two COST actions.  

Journal Reference

Daniel Micallef¹, Tonio Sant². Loading effects on floating offshore horizontal axis wind turbines in surge motion.  Renewable Energy, Volume 83, November 2015, Pages 737–748.

Show Affiliations

1. Department of Environmental Design, Faculty for the Built Environment, University of Malta, Malta
2. Department of Mechanical Engineering, Faculty of Engineering, University of Malta, Malta

 

 

Go To Renewable Energy

 

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: An assessment model for energy efficiency program planning in electric utilities: Case of Northwest U.S.

Significance Statement

Energy efficiency stands out with its potential to address a number of challenges that today’s electric utilities face, including increasing and changing electricity demand, shrinking operating capacity, and decreasing system reliability and flexibility. Being the least cost and least risky alternative, the share of energy efficiency programs in utilities’ energy portfolios has been on the rise since the 1980s, and their increasing importance is expected to continue in the future. Despite holding great promise, the ability to determine and invest in only the most promising program alternatives plays a key role in the successful use of energy efficiency as a utility-wide resource. This issue becomes even more significant considering the availability of a vast number of potential energy efficiency programs, the rapidly changing business environment, and the existence of multiple stakeholders.

This paper introduces a hierarchical decision modeling framework for energy efficiency program planning in electric utilities. The framework focuses on the assessment of emerging energy efficiency programs and proposes to bridge the gap between technology screening and cost/benefit evaluation practices. This approach is expected to identify emerging technology alternatives which have the highest potential to pass cost/benefit ratio testing procedures and contribute to the effectiveness of decision practices in energy efficiency program planning. The framework also incorporates rank order analysis and sensitivity analysis for testing the robustness of results from different stakeholder perspectives and future uncertainties in an attempt to enable more informed decision-making practices. An assessment framework was applied to the case of 13 high priority emerging energy efficiency program alternatives identified in the Pacific Northwest, U.S.A.

The results of this study reveal that energy savings potential (35.6%) is the most important program management consideration in selecting emerging energy efficiency programs. Market dissemination potential (25.7%) and program development and implementation potential (24.6%) are the second and third most important, whereas ancillary benefits potential (14.1%) is the least important program management consideration. The results imply that program value considerations (49.7%), comprised of energy savings potential and ancillary benefits potential; and program feasibility considerations (51.3%), comprised of program development and implementation potential and market dissemination potential, have almost equal impacts on assessment of emerging energy efficiency programs. Considering the overwhelming number of value-focused studies and the few feasibility-focused studies in the literature, this finding clearly shows that feasibility-focused studies are greatly understudied.

The hierarchical decision model developed in this paper is generalizable. Thus, other utilities or power systems can adopt the research steps employed in this study as guidelines and conduct similar assessment studies on emerging energy efficiency programs of their interest. 

About The Author

Dr. Ibrahim Iskin is a senior software engineer at Zuliliy corporation in Seattle Washington USA. His research focus is on data science specifically machine learning and big data. Prior to that he worked at XPO Logistics and Bonneville Power Administration. He has a BS in Industrial Engineering from Istanbul Technical University, MS in Engineering Management and PhD in Technology Management from Portland State University. 

About The Author

Tugrul Daim is a Professor and PhD Program Director in the Department of Engineering and Technology Management at Portland State University. Prior to joining PSU, he had worked at Intel Corporation for over a decade in varying management roles. At Intel he managed product and technology development. He also has several professional certifications including New Product Development Professional and Project Management Professional.

Professor Daim has been consulting to several organizations in sectors ranging from energy to medical device manufacturing. He has been helping organizations including US Dept of Energy, Energy Trust of Oregon, Biotronik, Biopro, Elsevier and many others to develop technology roadmaps for their future investments. He is also a visiting professor with the Northern Institute of Technology at Technical University of Hamburg, Harburg where he teaches similar short courses.

He has been recently appointed as Extraordinary Professor at the Graduate School of Technology Management at University of Pretoria in South Africa. He is frequently invited to give lectures to many multinational companies including IBM, Xerox and HP as well as universities  around the world including his recent visits to Finland, Japan and Germany. He has published over 200 refereed papers in journals and conference proceedings. His papers appeared in Technological Forecasting and Social Change, Technovation, Technology Analysis and Strategic Management, Computers and Industrial Engineering, Journal of Medical Systems, Energy, Energy Policy and many others. He has coauthored four books of readings and several proceedings.

He is the Editor-in-Chief of International Journal of Innovation and Technology Management and North American Editor of Technological Forecasting and Social Change. He received his BS in Mechanical Engineering from Bogazici University in Turkey, MS in Mechanical Engineering from Lehigh University in Pennsylvania, MS in Engineering Management from Portland State University, and PhD in Systems Science: Engineering Management from Portland State University in Portland Oregon. 

 

Journal Reference

Ibrahim Iskin, Tugrul U. Daim. An assessment model for energy efficiency program planning in electric utilities: Case of Northwest U.S. Sustainable Energy Technologies and Assessments, Volume 15, 2016, Pages 42–59.

Portland State University, Department of Engineering and Technology Management, Portland, OR 97207, United States.

 

Go To Sustainable Energy Technologies and Assessments

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Human health risks of post- and oxy-fuel combustion carbon dioxide capture technologies: Hypothetically modeled scenarios

Significance Statement

The two traditional power plant technologies for capturing carbon dioxide are the Post-combustion and Oxy-fuel combustion systems. In this study, the post-combustion capture system absorbs carbon dioxide using a solvent called monoethanolamine, which is representative of a family of amine-based solvents, from flue gases of a coal-fired electricity generating plant. The resultant carbon dioxide rich solvent is fed to the regenerator for removal of the carbon dioxide, and the lean monoethanolamine solvent is recycled for further carbon dioxide capture. In oxy-fuel combustion, fuel is combusted in pure oxygen and a recycled flue gas stream is used to dilute the oxygen and provide heat transfer, which results in a high carbon dioxide concentration in the flue gas.

Despite Boundary Dam Power Station’s capacity for preventing 90% of its produced greenhouse gases from emission into the atmosphere, both the post-combustion and oxy-fuel capture processes emit some gases that can be hazardous to human health.

Researchers from University of Regina in Canada evaluated the predicted risk to human health associated with the Boundary Dam Power Station in Estevan, Saskatchewan, Canada. The study, which was published in International Journal of Greenhouse Gas Control, predicted the potential instead of actual risks to human health because real data from the stack of the power plant are unavailable.  The study relied on results from a life cycle assessment study published in (Koiwanit et al., International Journal of Greenhouse Gas Control, 2014).

Amine is an effective solvent.  However, there are solvent losses during the process of post-combustion capture as well as the emission of toxic gases such as sulfur oxides (SO_X), nitrogen oxides (NO_X) and particulate matter (PM_2,5). The process also emits volatile products, largely degradation products of the amine, such as ammonia (NH₃), aldehydes, ketones, formaldehyde, nitrosamines and nitramines, all of which pose health concerns such as an increased risk of cancer.

The study of Koiwanit et al. (2016) adopted the Air Quality Benefits Assessment Tool (AQBAT) software package for conducting health risk evaluation and the pollutants PM_2.5, NO₂, SO_2, O₃ and CO were considered.

For modelling air dispersion and risk, the study adopted the regulatory model of the American Meteorological Society and the Environmental Protection Agency (AERMOD) and CALPUFF.  AERMOD is a steady-state Gaussian plume model, which assumes the dispersion concentration is described by a normal distribution. The model is designed to calculate pollutants in both simple and complex terrains in the same computational framework.  On the other hand, the CALPUFF system is a non-steady meteorological and air quality modelling system for complex terrains; it measures air quality in both near field ranges and as far as hundreds of kilometers away.

Data sources for the study included: (i) Canadian stack data provided by SaskPower, (ii) data from the study (Koiwanit, 2015), (iii) meteorological data specific to Estevan provided by the Saskatchewan Government, and (iv) data on emission rates from life cycle analysis studies of the Canadian lignite coal-fired power plant with and without carbon dioxide capture technology processes.  The data were all represented in MS® excel spreadsheets.

Health Canada’s air quality benefits assessment tool was used to estimate human risks or damage related to changes in ambient air quality. The data was analyzed in terms of a function, which is endorsed by Health Canada, for measuring the ambient air concentration response related to both chronic and acute human health outcomes.

The two technologies were compared based on three scenarios: conventional lignite-fired electricity generation station without carbon dioxide capture, lignite-fired electricity generation unit with an amine post-combustion capture system and an oxy-fuel combustion carbon dioxide capture system.

The studied system was located at Unit 3 of the Boundary Dam Power Station in Estevan, Saskatchewan, where emissions of NO_2, PM_2.5 and SO₂ were predicted for an area of 19.625 Km², which consists of a radial pattern of 10⁰ increments with 25 points of 100m laterally on each increment (up to 2500 m).

Results from modeling with AERMOD showed that even though most of particulate matter from the power plant was a result of the oxidation of SO_X and NO_X to solid-phased sulfate and nitrate, the oxidation process is slow and formation of particulates can occur outside the 2.5 Km radius from the power plant.

Results from modeling with AQBAT showed the NO₂ concentration affected only the change in health endpoint of acute exposure. The AQBAT modeling results on health outcomes of PM_2.5 showed that PM_2.5 was responsible for 14 health impacts, the five most important being acute respiratory symptom days, restricted activity days, asthma symptoms, child acute bronchitis, and adult chronic bronchitis. The AQBAT results on health outcomes of SO₂ showed that the pollutant had health impact only in terms of the acute exposure mortality rate.

The research study concluded that the oxy-fuel system had better performance in terms of environmental impacts when compared to the post-combustion CO₂ capture system. The oxy-fuel system showed better results in terms of reduction of acute respiratory problems, asthma, and restricted activity health outcomes. The two capture scenarios also demonstrated fewer adverse impacts on human health when compared to the no capture scenario. From the modeling results, among the pollutants, the PM_2.5 was responsible for more health risks than gaseous NO₂ and SO_2, each of which was associated with only one health outcome.

According to Koiwanit et al. (2016), future work needs to be conducted using the modeling tool of AQBAT to assess health impacts of mercury and heavy metals, which were not taken into account in the study.

REFERENCE

Koiwanit, J. (2015). Evaluation of environmental performance of hypothetical Canadian oxy-

fuel combustion carbon capture with risk and cost analyses. (Ph.D Thesis, University of

Regina, Regina, SK).

Koiwanit, J., Manuilova, A., Chan, C., Wilson, M., & Tontiwachwuthikul, P. (2014). A life cycle assessment   study of a hypothetical Canadian oxy-fuel combustion carbon dioxide capture process. International Journal of Greenhouse Gas Control, 28, 257-274.

Koiwanit, J., Manuilova, A., Chan, C., Wilson, M., Tontiwachwuthikul, P. Human Health Risks of Post- and Oxy-Fuel Combustion Carbon Dioxide Capture Technologies: Hypothetically Modeled Scenarios. (2016). International Journal of Greenhouse Control, 47, 279-290.

 

 

About The Author

Dr. Jarotwan Koiwanit  is currently a Lecturer of Engineering in Industrial Engineering at the Faculty of Engineering of King Mongkut’s Institute of Technology Ladkrabang in Thailand. She received her Bachelor’s degree in Industrial Engineering from Thailand and was ranked first amongst the students in the program. She also got a Master degree in Industrial Engineering from Thailand as well as a Ph.D. degree in Industrial Systems Engineering from the University of Regina, located in Saskatchewan, Canada. Whilst in Canada, she received scholarships both from the University of Regina and the Government of Saskatchewan. Based on work she completed during her Ph.D. funded project, she published five journal papers and two conference papers. Two papers that were published in the International Journal of Greenhouse Gas Capture (Elsevier) were selected as Key Scientific Articles contributing to excellence in Energy Research by Renewable Energy Global Innovations in 2015 and 2016. She has also contributed to several presentations at national and international conferences.  She has a superior academic record and generates sound, publishable research results.

In 2016, Jarotwan was the Director of CU Innovation Academy, and the CU Innovation Hub for Chulalongkorn University in Thailand. She was also a guest lecturer at Thailand’s International School of Engineering (ISE), in Chulalongkorn University’s Faculty of Engineering. She has more than six years of experience in the areas of carbon capture and storage (CCS), life cycle assessment (LCA), and greenhouse gas (GHG) accounting. She has also been involved in many research projects and her specialties are in quality management and statistical quality control, air dispersion modeling, and health risk assessment. 

About The Author

Dr. Anastassia Manuilova is Vice President, Energy and Environment at ArticCan Energy Services, a multi-disciplinary engineering consulting company. She oversees operations of the Engineering Branch and leads the Energy and Environment division. Anastassia’s distinct and stimulating career path of 17 years has seen her working across many industries including pharmaceuticals, chemicals and consumer products manufacturing, oil & gas, power, and research and technology commercialization, where she has led and executed a variety of environmental projects and sustainability initiatives.

Anastassia holds a B.Sc. degree in Chemical and Environmental Engineering from Estonia and an M.Sc. degree in Environmentally Sustainable Process Technology from Chalmers University of Technology in Sweden. She also has a Ph.D. in Environmental Systems Engineering from the University of Regina. 

 

About The Author

Dr. Christine W. Chan has been Canada Research Chair Tier 1 in Energy and Environmental Informatics since 2006, and she is Professor of Engineering in Software Systems Engineering at Faculty of Engineering and Applied Science of University of Regina in Saskatchewan, Canada. Dr. Chan received M. Sc. degrees in Computer Science and Management Information Systems from the University of British Columbia, and the Ph.D. degree in Applied Sciences from Simon Fraser University.

She served as a member of the Expert Panel on the Potential for New and Innovative Uses of Information and Communications Technologies (ICT) for Greening Canada, organized by the Council of Canadian Academies.

She is Editor of Engineering Applications of Artificial Intelligence and Area Editor of International Journal of Information Technology and Social Change.  She also serves as Editorial Board Member of another four international journals.

One of her papers won the Top Ten Most Cited Article 2005-2010 Award of the journal of Engineering Applications of Artificial Intelligence (Elsevier), and two papers published in International Journal of Greenhouse Gas Capture (Elsevier) were selected as Key Scientific Articles contributing to excellence in Energy Research by Renewable Energy Global Innovations in 2015 and 2016.

She is founder and principal investigator of the Energy Informatics Laboratory at the University of Regina. She has published over 270 technical publications, of which over 100 are in international journals.  

About The Author

Dr. Malcolm A. Wilson received his BSc from the University of Nottingham (1972), and his MSc (1977) and PhD (1981) from the University of Saskatchewan.

Malcom is currently the COO of a Regina-based bioenergy company, Prairie Biogas Ltd. He is also the VP for a second bio-energy company New World Orange Biofuels and CEO of ArticCan Energy, an engineering company. In 1998, Malcolm played a significant role in the establishment of the Petroleum Technology Research Centre (PTRC) in Regina, Saskatchewan, Canada. After having served on the board of PTRC, he became the CEO in January, 2011 and stayed until June 2013.

He is currently active on an ISO committee (ISO TC265), which is developing voluntary standards for CO₂ Capture, Transport and Storage. He remains Adjunct Professor in the Faculty of Engineering and Applied Science at the University of Regina, and was appointed Adjunct Professor at the University of Hunan, China, in 2012.

Malcolm was the Director of the Office of Energy and Environment at the University of Regina from 2000 – 2010, prior to which he worked for Saskatchewan Energy and Mines for twenty years. He was instrumental in the creation of the IEAGHG Weyburn-Midale CO₂ Monitoring and Storage Project, a world recognised CO₂ storage research project, including editing the final report of phase one.

Malcolm was a member of Working Group III of the Intergovernmental Panel on Climate Change (IPCC), the scientific team awarded the 2007 Nobel Peace Prize jointly with Al Gore. He also founded the Prairie Adaptation Research Collaborative (PARC), serving as its first Head. He is a member of the Board of Directors for Canada-Ukraine Centre, Inc. (CUC) and has been a contributor to the technology transfer project with Ukraine.

In 2009, Malcolm was awarded the University of Saskatchewan Alumni Award of Achievement for outstanding contributions to profession, community and the University of Saskatchewan.  In the same year, Saskatchewan Business Magazine named him one of Saskatchewan’s ten most influential men.

In 2013 he was recognised as one of five influential people in the Province’s oil industry. He was the joint winner of the 2006 Natural Sciences and Engineering Research Council of Canada (NSERC) Synergy Award for his work with the International Test Centre for CO₂ Capture, which he helped found and fund. 

About The Author

Dr. Paitoon (P.T.) Tontiwachwuthikul received B.Eng. degree in Chemical Engineering from King Monkut’s Institute of Technology, Thonburi, Thailand. He received his M.Eng and Ph.D. degrees in Chemical Engineering from the University of British Columbia.

He is a key international researcher in the technologies of advanced CO₂ capture and separation from industrial gas streams; he has provided technical advice to governments and industries nationally and internationally. He is the co-founder of Clean Energy Technologies Research Institute or CETRI (formally known as the International Test Centre for CO₂ Capture or ITC) in Canada.

He has served as Associate Editor of International Journal of Greenhouse Gas Control (IJGGC, Elsevier), and as the guest editor of the IEA-GHG special issue on “IEA Weyburn-Midale CO₂ Monitoring and Storage Project (the world’s largest CO₂ for EOR and CCS program)” of IJGGC, published in May 2013.

He and his team developed 8 patents (US and International) in the areas of advanced carbon capture processes and clean energy technologies; they completed an eBook on “Recent Progress and New Development of Post Combustion Carbon Capture (PCC) Technology Using Reactive Solvents”, published by Future Science (UK) in October 2013.

He has extensive experience in collaborative work with the industry. He was involved in the Research Consortium of ITC, which received in-kind and financial support from granting organizations such as NSERC (Strategic Projects, Discovery, RTI and IOR), Canada Research Chair Program, Canada Foundation of Innovation, NCE, PTRC, Telecommunications Research Laboratory (TRLabs), SaskPower, SaskEnergy/Transgas, City of Regina, EnCana, Saudi Aramco, Research Institute of Innovative Technology for the Earth (RITE) of Japan, Alberta Energy Research Institute (AERI), Natural Resources Canada, and Saskatchewan Energy and Resources.

He was awarded a NCE-Carbon Management Canada research grant in 2010, which supported the preliminary study on lifecycle assessment of the carbon capture technologies, and generated more than 10 publications on life cycle impact assessment (LCIA) and low-carbon energy development. In the past six years, his joint publications included 16 journal publications, 2 book chapters, and 10 conference papers. 

Journal Reference

Jarotwan Koiwanit¹, Anastassia Manuilova², Christine Chan¹ , Malcolm Wilson², Paitoon Tontiwachwuthikul¹ . Human Health Risks of Post- and Oxy-Fuel Combustion Carbon Dioxide Capture Technologies: Hypothetically Modeled Scenarios. International Journal of Greenhouse Gas Control, Volume 47, April 2016, Pages 279–290.

Show Affiliations

1. Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, Canada S4S 0A2
2. ArticCan Energy Services, Regina, Saskatchewan, Canada S4S 0A2.

 

 

Go To International Journal of Greenhouse Gas Control

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Effect of salt and sodium concentration on the anaerobic methanisation of the halophyte Tripolium pannonicum

Significance Statement

The objective of this research work is to analyse the potential use of halophytes as biofilter to decrease contaminants in water and their further use for biogas production through an anaerobic digestion process. This is an environmentally friendly method where plants are used for biofiltration and besides the plant material used as substrate produces biogas which is a renewable energy source (Fig. 1).

Halophytes are plants that tolerate high concentrations of soluble salt in their environments. Since most wastewaters contain dissolved salts and halophytes are able to uptake and store salt in their tissues, it is important to study the salt inhibition during the fermentation process.  

About The Author

Ariel E. Turcios is a researcher in the field of water resources, biomass & bioenergy at Leibniz University Hanover, Germany. At present he is a PhD student in Biology at the same university. He has published relevant scientific papers related to potential use of salt tolerant plants for biofiltering to decrease organic and inorganic contaminants in the water and their further use for biogas production through the anaerobic digestion process. His educational background includes a M.Sc. in water resources management and a Bachelor in Agricultural Engineering.

Ariel has been awarded several times during his academic career. During his Bachelor, Ariel received a Prize for academic excellence because he achieved the highest mark during the whole career in the Agronomy Faculty of the Universidad de San Carlos de Guatemala.

He also was awarded in his Master studies with the Prize “The best Master Thesis”. During his PhD studies, Ariel also received the award of the Christian-Kuhlemann Foundation for his outstanding scientific achievements and social and cultural commitment at Leibniz University Hanover, Germany.  

Journal Reference

Ariel E. Turcios^1,2 , Dirk Weichgrebe³ , Jutta Papenbrock¹. Effect of salt and sodium concentration on the anaerobic methanisation of the halophyte Tripolium pannonicum. Biomass and Bioenergy, Volume 87, 2016, Pages 69–77.

Show Affiliations

1. Institute of Botany, Leibniz University Hannover, Herrenhäuserstr. 2, D-30419, Hannover, Germany.
2. Facultad de Agronomía, Universidad de San Carlos de Guatemala, Guatemala.
3. Institute for Sanitary Engineering and Waste Management, Leibniz University Hannover, Appelstr. 9a, D-30167, Hannover, Germany

 

 

Go To Biomass and Bioenergy

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Response of soil carbon dioxide fluxes, soil organic carbon and microbial biomass carbon to biochar amendment: a meta-analysis

Significance Statement

Researchers from Nanjing Agricultural University reviewed 395 individual experiment observations derived from 50 peer-reviewed publications which were synthesized to examine the response of soil carbon dioxide fluxes, soil organic carbon and microbial biomass carbon (MBC) to biochar amendment using meta-analysis procedures. Their work published in journal, Global Change Biology Bioenergy examined the effect of size of biochar amendment on soil carbon dioxide fluxes, SOC and MBC contents and identified the key factors that influence the response of soil carbon dioxide fluxes, soil organic carbon and microbial biomass carbon to biochar amendment.

Biochar as carbon-rich co-product of pyrolysis biomass subject to high-temperature and oxygen-derived conditions for biofuel production has been advocated as potential management strategy to improve soil quality, crop yield increase and soil carbon sequestration enhancement.

In order to have an understanding on the effects of soil carbon dioxide and microbial biomass carbon, there is need to have deeper understanding on how biochar amendment effects whether negative or positive. However, inconsistent results from various researchers was observed which may be due to variation in soil type or study methods.

Experiments examined by researchers have shown no systematic synthesis as potential biochar amendment to improve soil carbon sink capacity and its effect on soil carbon dioxide are still under debate in which direction and magnitude of effects seem to depend on variety of factors such as soil properties, land-use type, experimental methods, vegetation presence and biochar characteristics.

For implementation of the experiment the authors conducted a detailed review of literature published in peer-reviewed journals through the year 2014 and data was extracted from 50 published research papers with 395 individual observations including both control and biochar-amended treatments.

For measurement, original documentation included mean soil carbon dioxide fluxes, standard deviation and number of replicates from both biochar-amended and control treatments as well as direction and magnitude of effects stated earlier.

Means of soil carbon dioxide fluxes, soil organic carbon and microbial biomass carbon contents from biochar treatment and control groups were used to compute effect sizes in the form of natural log-transformed response ratio (RR). Meta-analysis was conducted using response ratios where mean effect size for each category was calculated using a categorical random effects model. In addition to meta-analysis procedure, fitting of data to linear and Gaussian distribution functions were carried out using SigmaPlot version 12.0 software. Sensitivity analysis also followed suit in order to test the robustness of meta-analysis.

Results showed a significantly positive linear relationship as observed between soil carbon dioxide fluxes in biochar amended and control likewise soil organic carbon and microbial biomass carbon contents but carbon dioxide flux wasn’t significant. Key factors mediating carbon dioxide fluxes were seen to be soil texture, pH, vegetation presence, feedstock presence and carbon-nitrogen ratio to biochar amendment. Land-use type and biochar carbon to nitrogen ratio were two critical parameters affecting response of soil organic content while microbial biomass carbon response to biochar amendment was sensitive to almost all parameters.

For land-use change, biochar amendment significantly increased soil organic carbon content 40% across all ecosystem but increased significantly with biochar treatments found in rice paddies. In soil carbon, biochar amendment significantly decreased carbon dioxide fluxes on pot experiments but positive effects was seen in laboratory incubations. There was decrease in microbial biomass carbon by biochar amendment in incubation and pot studies but greatly increased soil organic carbon content when using the three pots.

For soil texture and pH, biochar amendment in coarse soils exerted a significant positive effects on soil carbon dioxide fluxes while significant negative effects were observed in fine-textured soils which had similar result with microbial biomass carbon significantly. Biochar was effective at decreasing soil carbon dioxide fluxes but did not benefit soil organic carbon enhancement in neutral or alkaline soils and significant positive responses of soil carbon dioxide fluxes were observed in moderately acid soils. Soil microbial biomass carbon content was significantly increased by biochar amendment in acid soils relative to in neutral or alkaline soil conditions.

Biochar amendment significantly increased soil carbon dioxide fluxes when synthetic nitrogen fertilizer was applied. Soil organic carbon content by biochar amendment did not significantly differ in soils with or without nitrogen fertilizer application but organic nitrogen fertilizer had the largest increment potential for soil organic carbon. Biochar addition had significantly positive effect on microbial biomass carbon when combined with nitrogen fertilizer or synthetic nitrogen fertilizer.

In meta-analysis, removal of outliers did not change the general results. After removing outliers, the mean effect sizes of biochar treatments was 5% (Cl: -2% to 12%) for carbon dioxide, 40% (Cl: 30% to 58%) for soil organic carbon and 19% (Cl: 12% to 24%) for microbial biomass carbon comparable to 5% (Cl: -3% to 12%), 40% (Cl: 32% to 56%) and 18% (Cl: 12% to 23%) for carbon dioxide, soil organic carbon and microbial biomass carbon when all datasets included respectively.

Limited range of study durations did not allow examination of effect of biochar aging on soil carbon dioxide fluxes, soil organic carbon and microbial biomass carbon in meta-analysis, hence field experiment with longer durations across a wider range of spatial and temporal scales are required.

About The Author

Jianwen Zou, Ph.D., Professor

College of Resources & Environmental Sciences- Jiangsu Key Laboratory of Low Carbon Agriculture & GHGs Mitigation, Nanjing Agricultural University, China

Jianwen Zou, National Outstanding Young Scientist Award, Premium Professor of Jiangsu Province, and he is also the Director of Jiangsu Key Laboratory of Low Carbon Agriculture & GHGs Mitigation, Vice Dean of College of Resources & Environmental Sciences in Nanjing Agricultural University.

He is also the member of Sector of Agriculture and Forest, Science & Technology Commission of Ministry of Education, China. His research focuses on soil carbon and nitrogen cycling and global change, agricultural greenhouse gases accounting and mitigation.

 

Journal Reference

Shuwei Liu^1,2,Yaojun Zhang^1,2,Yajie Zong^1,2,Zhiqiang Hu^1,2,Shuang Wu^1,2,Jie Zhou^1,2,Yaguo Jin^1,2,Jianwen Zou^1,2. Response of Soil Carbon Dioxide Fluxes, Soil Organic Carbon and Microbial Biomass Carbon to Biochar Amendment: A Meta-Analysis. Global Change Biology Bioenergy, 2016, Volume 8, pp 392-406.

Show Affiliations

1. Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing Agricultural University, Nanjing, China
2. Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China

 

 

 

Go To GCB Bioenergy

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Comparison of two pelleting methods for cellulosic ethanol manufacturing: ultrasonic vibration-assisted pelleting vs. ring-die pelleting

Significance Statement

Cellulosic ethanol made from cellulosic biomass serves as a renewable alternative to petroleum-based liquid transportation fuels. Cellulosic ethanol production from cellulosic biomass offers various advantages in terms of little competition with limited agricultural lands, rural economic development, reduction in greenhouse gas, improvement of soil fertility and agricultural ecology.

 A new study by Zhang et al. (2016) and published in Journal, Biomass Conv. Bioref. compared pellet quality, temperature, energy consumption and sugar yield of corn stover processed by ultrasonic vibration-assisted pelleting versus ring-die pelleting with two levels of sieve sizes.

Cost effectiveness due to transportation and storage of low-density cellulosic biomass has been a major challenge to cellulosic ethanol. Pelleting significantly increases density of raw cellulosic biomass ranging from 40 to 250kg/m³ to over 600kg/m³. This definitely reduces the cost of transport and storage of raw cellulosic biomass which also makes them have uniform physical features for easier handling.

Two pelleting methods for cellulosic biomass include traditional pelleting methods (press briquetting, screw extruding and ring-die) and ultrasonic vibration-assisted. The former makes use of high temperature steam, high pressure and often binder materials while the latter does not involve high temperature steam, high pressure and binder materials. Ultrasonic vibration-assisted have been known to produce pellets with same density and durability as that of traditional pelleting methods with high sugar yield.

Corn stover was baled and transported to Bioprocessing and Industrial value-added program. The chopped corn stover was milled into two particle levels using a 7.4KW hammer mill. After hammer milling, moisture content of corn stover particles was measured and adjusted to a desired level by following NREL laboratory procedure.

Ultrasonic vibration-assisted pelleting was conducted on a modified ultrasonic machine which composed mainly of three systems such as an ultrasonic generation system, a pneumatic loading system and biomass holding system, as shown in Fig.1. Five steps in making of pellet in ultrasonic vibration-assisted machine include; assembly and feeding of pelleting tool done to compress corn stover particles, turn on ultrasonic power supply and apply ultrasonic vibration, turn off ultrasonic power supply and lift up pelleting tool after pelleting duration and disassembly of mold to take out pellet.

Figure Legend 1. Ultrasonic vibration-assisted pelleting.

Experimental setup for ring-die pelleting had steam conditioning chamber by a screw feeder rotating at 7rpm. Major reasons for variables such as rotation speed of ring die, diameter and length of ring die channel include; commonly used values in literature and values that can produce pellets with high density and durability.

Pellet density was calculated as ratio of its weight over its volume. Pellets volume were obtained by measuring pellet height with diameter and each was measured three times. 100g instead of 500g of pellets were used to measure pellet durability based on ASABE standard S269.4.

Sugar yield was measured as amount of glucose obtained after pretreated enzymatic hydrolysis. Concentration of glucose solution in Autosampler vials was determined by a high-performance liquid chromatography. Measurement of temperature was achieved by using thermocouples, thermometer and a computer with data acquisition software package. Scanning Electron Microscopy was used to observe pellet microstructure of biomass.

Results from experiment showed both ultrasonic vibration-assisted and ring-die method had density higher than 900kg/m³ which is higher than that of raw cellulosic biomass, as shown in Fig 2. When smaller sieve size (3.2mm) was used, mean value of Ultrasonic Vibration-Assisted pellet density was 1100kg/m³ about 11% higher than that of ring-die pellet. When large sieve size (9.5mm) was used, mean value of Ultrasonic Vibration-Assisted pellet density was 1034kg/m³, about 6% higher than ring-die pellets.

Figure Legend 2: Comparison of pellet density between UV-A pelleting and ring-die pelleting.

 

Figure 3 shows that both pellets from ring-die method and ultrasonic vibration-assisted had pellet durability higher than 90%. When smaller sieve size (3.2mm) was used, pellet durability of ultrasonic vibration-assisted and ring-die pellets were 98.5% and 94.4% respectively. When larger sieve size (9.5mm) was used, pellet durability of Ultrasonic Vibration-Assisted pellets and ring-die pellets were 93.4% and 91.2% respectively.

Figure Legend 3: Comparison of pellet durability between UV-A pelleting and ring-die pelleting.

Results on sugar yield showed smaller particles (3.2mm sieve) 67.1% and 60.9% for ultrasonic vibration-assisted pellets and ring-die pellets respectively while larger particles (9.5mm sieve) sugar yield of ultrasonic vibration-assisted pellets and ring-die pellet was 59.9% and 54.9% respectively, as shown in Fig.4.

Figure Legend 4: Comparison of sugar yield between UV-A pelleting and ring-die pelleting.

The increasing rate of temperature in ultrasonic vibration-assisted pelleting was faster than that of ring-die pelleting. Energy consumption of ultrasonic vibration-assisted pelleting (296-310KWh/ton) was almost three times higher than that of ring-die pelleting (122-125KWh/ton), as shown in Fig. 5. The lab-scale setup of ultrasonic vibration-assisted was known to limit its efficiency.

Figure Legend 5: Comparison of energy consumption between UV-A pelleting and ring-die pelleting.

Scanning Electron Microscopy results inferred high pelleting temperature and shear forces during pelleting softened biomass surface and exposed more microfibrils which aids in enzymatic hydrolysis resulting in high sugar yield, as shown in Fig.6.

Figure Legend 6: Biomass microstructure after UV-A pelleting.

Zhang et al. (2016) study on comparison of corn stover pellets in ultrasonic vibration-assisted pelleting and ring-die pelleting showed that the former has a potential to be further developed and more research needs to be done to improve its pelleting efficiency and reduce energy consumption.

About The Author

Dr. Qi Zhang is an Associate Professor and deputy director of Mechanical Engineering at Yangzhou University, China. In 2013, she obtained her Ph.D. degree in Industrial and Manufacturing Systems Engineering at Kansas State University, USA.

She has accomplished several projects from National Science Foundation (NSF) and Department of Energy (DOE) as a searcher in USA since 2009. Her research interest is conversion of cellulosic biomass into renewable energy (biofuel). She obtained funds from government of Jiangsu Province (China) to develop a pretreat method and pelleting method using ultrasonic technology to improve cellulose-to-sugar conversion rate in biofuel manufacturing.

Her research areas include reliability-based design optimization, biomass conversion, and ultrasonic machining. She has published more than 30 papers and served as a reviewer for many prestigious journals such as Applied Energy.

 

About The Author

Dr. Pengfei Zhang is a research scientist and technical director in Jiangsu Muyang Holdings Co. Ltd (Muyang), one of the largest feed & grain processing equipment company in the world. He obtained his Ph.D. degree in Industrial and Manufacturing Systems Engineering at Kansas State University, USA in 2011. He worked at KSU as a research assistant professor from 2012 to 2013. He accomplished many projects from NSF and DOE as a key searcher in the USA. Now he is in charge of feed and biomass drying technology and manage dryer design department. He conducts research in air flow and heat exchange using computational fluid dynamics.

He has published more than 30 papers and one of his major research goals is to save energy consumption in feed and food industry.

 

About The Author

Dr. Z.J. Pei is a professor in the Department of Industrial & Systems Engineering at Texas A&M University. His research areas include machining processes (such as Rotary Ultrasonic Machining) for difficult-to-machine materials and renewable energy. His current research interests are in cyber-manufacturing systems and additive manufacturing.He has published more than 100 journal papers.

He has served as a program Director for the NSF Manufacturing Machines and Equipment (MME) program in 2012-2016. He has obtained more than 4 million dollar NSF Grants during his faculty career by now. He is a Fellow member of American Society of Mechanical Engineers (ASME) and Society of Manufacturing Engineers (SME).

 

About The Author

Dr. Donghai Wang is a professor in Department of Biological and Agricultural Engineering at Kansas State University. He conducted research in quality measurement of biological materials using Near-Infrared Spectroscopy, grain processing including drying, dry and wet-milling of grains, bioconversion and biomaterials.

His research focuses on bioconversion of agricultural materials and by-products into biofuels, chemicals and other value-added products, and development of biodegradable materials from renewable recourse.

About The Author

Lin Hen a master student at school of Mechanical Engineering in Yangzhou University.

About The Author

Dr. JiPing Zhou is a professor in school of Mechanical Engineering at Yangzhou University. His research focuses on electrical control and automation equipment of robots and 3D printing equipment. He received many national-level government supported grants. He is a fellow member of China Society of Mechanical Engineers (CSME).

Journal Reference

Qi Zhang^1,2, Lin Heng¹, Pengfei Zhang^2,3, Z. J. Pei², Donghai Wang⁴, Jonathan Wilson⁵, JiPing Zhou¹ . Comparison of two pelleting methods for cellulosic ethanol manufacturing: ultrasonic vibration-assisted pelleting vs. ring-die pelleting.  Biomass Conversion and Biorefinery, March 2016, Volume 6, Issue 1, pp 13–23.

Show Affiliations

1. College of Mechanical Engineering, Yangzhou University Yangzhou China.
2. Department of Industrial and Manufacturing Systems Engineering, Kansas State University Manhattan USA.
3. Jiangsu Muyang Holdings Yangzhou China.
4. School of Biological and Agricultural Engineering, Kansas State University Manhattan USA.
5. Department of Grain Science and Industry Kansas State University Manhattan USA.

 

 

Go To Biomass Conversion and Biorefinery

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Strategical location map for photovoltaic power systems from environmental view point

Significance Statement

It’s well known that there are abundant sunlight and huge land in deserts. For example, comparing annual irradiation in Tokyo and in Sahara desert, the Sahara has 2685 kWh/m² which is twice as 1268 kWh/m² in the Tokyo. The deserts must be good for photovoltaic power systems. This is the first idea to start this research. Japanese research team started a feasibility study of installation of the photovoltaic power systems in deserts in large-scale use, which should be considered distance to the desert for transport and power transmission, and the harshness of desert. It was two decades ago. At that period, photovoltaic power systems were very expensive, and was used for remote area where it is not easy to install transmission lines.

The team built up international expert members under the umbrella of the Photovoltaic Power System Programme (PVPS) in the International Energy Agency (IEA). Members are not only electrical engineers but also financial, agricultural, soil and environmental expert were gotten together. The study was so interesting and good experiences of communication. However it was successfully finalized. Their four reports titled ‘Energy from the Desert’ were published, and the last version is available for free on the website of the IEA/PVPS.

This paper is continuation of the study. By the end of the Task 8, two research topics had been done. One is life-cycle assessment (LCA) of the very-large scale photovoltaic power systems (VLS-PV) installed in deserts, and remote sensing using satellite images to find stable land condition to identify suitable location for the VLS-PV in deserts. An irradiation map shows center of desert is the best place. However, it takes a lot of energy to transport huge amount of equipment, and need long transmission lines to cities. From the environmental and economical view point, it should be not good. Therefore, my paper focuses on the distance to include for an economical and environmental study. For this purpose, a geographical information system (GIS) was introduced to calculate differences of locations.

This figure is a map of CO₂ emissions of Photovoltaic systems. This is calculated from four type of data. They are results from LCA, irradiation data, City location for power transmission and Ports to import equipment. All they got together, and the map was published. It is easy to know locations where the Photovoltaic system can generate electricity with lower CO₂ emissions. Very high potential locations could be obtained in North Chili, east and west Sahara, and Mexico.

About The Author

Masakazu Ito, He is an associate professor at the Advanced Collaborative Research Organization for Smart Society (ACROSS) in the Waseda University in Japan. He is researching Life-Cycle Assessment of PV systems, Geographical Information Systems, and the smart grid technologies, especially those with PV systems, wind power and energy storages. He earned his Ph.D. from the Tokyo University of Agriculture and Technology. He was a Research Fellow of Japan Society for the Promotion of Science (JSPS) while he was Ph.D. student. He started as an assistant professor in the Tokyo Institute of Technology, and then became a JSPS overseas research fellow at the CEA at INES in France, researching the Life Cycle Analysis (LCA) and remote sensing for Very Large Scale Photovoltaic Systems.

He was a member of International Energy Agency (IEA), Photovoltaic Power System Programme (PVPS), Task8: Very large scale photovoltaic power generation systems in remote areas and Task12: PV environmental health and safety. He awarded several prize; Academic Researcher Award by the Tokyo University of Agriculture and Technology in 2004, Naoaki Ito Award (Special Encouragement Award) by Japan Solar Energy Society in 2012, Young Researcher Award by 17th International Photovoltaic Science and Engineering Conference (PVSEC-17) in 2007, Young Researcher Award by 3rd World Conference on Photovoltaic Energy Conversion (WCPEC-3) in 2003, and so on. 

Journal Reference

Masakazu Ito¹, Sylvain Lespinats¹, Jens Merten¹,Philippe Malbranche¹, Kosuke Kurokawa². Life cycle assessment and cost analysis of very large-scale PV systems and suitable locations in the world. Progress in Photovoltaics: Research and Applications, Vol 24 Issue 2, 2016.

Show Affiliations

1. Laboratory for Solar Systems, Institut National d’Energie Solaire (INES), CEA, Le Bourget du lac Cedex, France
2. AES Center, Tokyo Institute of Technology, Tokyo, Japan

 

 

Go To Progress in Photovoltaics: Research and Applications

 

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Adjustment of wind farm power output through flexible turbine operation using wind farm control

Significance Statement

With high penetration of wind power, the power generated by wind farms can no longer simply be that dictated by the wind speed. It will be necessary for wind farms to provide services to the grid including spinning reserve, frequency support and assistance with supply-demand matching. In these circumstances, to regulate the power generated by the wind farm to match the grid requirements, a wind farm controller, causing the power generated by each turbine to be adjusted, is required.

This study proposes a flexible, hierarchic, decentralized and scalable approach to wind farm control that can be used to maximize the aggregated wind farm power output and/or to follow a reference for the aggregated wind farm power output, taking into account fatigue loading on each wind turbine. It is capable of providing fast and accurate control of the power generated by the wind farm in the below and above rated wind speed without compromising the turbines’ own full envelope controllers through enclosing them in an additional feedback.

The wind farm controller has two elements, the Network Wind Farm Controller (NWFC) and the Turbine Wind Farm Controller (TWFC). The NWFC acts on information regarding the state of the power network to determine the required power output from the wind farm and hence the adjustment relative to the wind speed dictated wind farm power output, which would arise with no adjustment. The TWFC acts on information regarding the state of the wind farm and the turbines therein to allocate adjustments to each turbine relative to the wind speed dictated turbine power output.

The simulation results in Matlab/SIMULINK^® and DNV GL BLADED demonstrate that the wind farm power output could be curtailed for an unlimited period of time and increased for a limited period of time to match the wind farm power demand while keeping each turbine in a safe operating region. It is also demonstrated in the frequency domain that the wind-farm controller does not cause a significant feedback effect that could compromise the effectiveness of the turbines full envelope controllers; that is, redesigning or re-tuning of the existing full envelope controller is not necessary.

 

 

 

 

 

 

About The Author

Dr. Sung-ho Hur received the B.Eng. degree in Electronics and Electrical Engineering (EEE) from the University of Glasgow in 2004 and the M.Sc. degree (with Distinction) in EEE from the University of Strathclyde in 2005. He then worked as a Research Assistant in the Industrial Control Centre (ICC) within the Department of EEE at the University of Strathclyde before undertaking a Ph.D. in the ICC in 2006.

During the Ph.D., which was fully supported by an EPSRC Industrial CASE scholarship with DuPont Teijin Films UK Ltd, he conducted research on modelling, cross-directional control and fault monitoring of a plastic film manufacturing process.

Since completing his Ph.D. in 2010, he has been working as a Research Associate in the wind energy group at the University of Strathclyde, researching in control, modelling and anomaly detection of wind turbines and farms. 

 

About The Author

Prof. Bill Leithead joined the Department of Electronic and Electrical Engineering at the University of Strathclyde in 1986 and has been Professor of Systems and Control Engineering since 1999 and Director of the Industrial Control Centre since 2006.

The wind energy group, which he established in 1988, is now one of the largest in the world with more than 70 researchers. He is Director of EPSRC Centre for Doctoral Training in Wind Energy and Marine Systems, which was established in October 2009, and Chair of Supergen Wind Hub. He has published more than 200 publications and been the recipient of more than 40 research grants. 

 

Journal Reference

Sung-ho Hur,William E. Leithead. Adjustment of Wind Farm Output Through Flexible Turbine Operation Using Wind Farm Control. Wind Energy, 2016, Volume 19, pp 1667-1686.  

Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow, UK.

 

Go To Wind Energy

 

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)

Renewable Energy Global Innovations features: Impacts of co-firing biomass on emissions of particulate matter to the atmosphere

Significance Statement

Since 2003, University of Iowa Facilities Management has worked to reduce the use of fossil fuels by replacing it with biomass, a process termed co-firing. Burning any fuel releases a cornucopia of substances into the atmosphere. Burning coal releases carbon dioxide, the most significant driver of greenhouse warming; sulfur dioxide and nitrogen oxides that contribute to acid rain and smog; particulate matter that can contribute to cardiovascular and respiratory disease; carcinogens such as polycyclic aromatic hydrocarbons (PAH), and many potentially toxic and/or carcinogenic metals.

Emissions tests were undertaken in April-May 2014 to determine how co-firing affects emissions of air pollutants. Co-firing 50% oat hulls (by weight) was found to significantly reduce a wide range of airborne pollutants. Criteria pollutants showed substantial reductions: carbon dioxide from fossil sources decreased by 39%, sulfur dioxide emissions dropped by 40%, and filterable particulate matter fell by 90%.  PAH, defined as hazardous air pollutants, decreased by 41%. Meanwhile, total metals dropped by 51%, with substantial reductions in manganese, copper, nickel, and zinc.

Decreases in pollutant emissions are attributed to the lower levels of sulfur and metals in biomass compared to coal requiring less limestone be input to the fluidized bed boiler to control sulfur dioxide, and the fact that oat hulls burn rather completely, leaving less unburned carbon behind.

About The Author

Armando D. Estillore obtained his B.S. in chemistry from MSU-IIT, Iligan City, Philippines and his Ph.D. in physical chemistry from Wayne State University under Prof. Arthur G. Suits in 2012. His doctoral work on the reaction dynamics of radicals with polyatomic hydrocarbons using crossed-beam ion imaging techniques earned the Dan Trivich Memorial Award for research in physical chemistry.

He was a Camille and Henry Dreyfus Postdoctoral Fellow in Environmental Chemistry at UC Berkeley prior to joining the group of Prof. Vicki H. Grassian at the University of Iowa and the University of California, San Diego where he is currently a postdoctoral researcher. 

About The Author

Ibrahim Al-Naiema is doctoral student in Chemistry at the University of Iowa. His research focuses on analyzing organic compounds in the atmospheric aerosols and understanding their sources. He received his M. Sc. in chemistry at the University of Basrah, Iraq, and worked as a lecturer at the same university for six years before joining Stone research group in 2012.  

About The Author

Elizabeth A. Stone is an Associate Professor in the Department of Chemistry at the University of Iowa. She earned her bachelor of art’s degree from Grinnell College in 2005 with majors in Chemistry (with honors) and French (with honors).  She completed her doctoral degree in 2009 from the University of Wisconsin-Madison in Environmental Chemistry & Technology for her thesis entitled Source Apportionment of Carbonaceous Aerosol in Different Regions of the World.

Since joining the University of Iowa in 2010, her research has focused on advancing our understanding of the chemical composition and sources of particulate matter in the atmosphere, through a combination of analytical, environmental, and organic chemistry.  She uses chromatography and mass spectrometry to improve measurements of atmospheric pollutants and source apportionment techniques to link pollution to its sources. 

Journal Reference

Ibrahim Al-Naiema^1,2, Armando D. Estillore¹, Imali A. Mudunkotuwa¹, Vicki H. Grassian¹, Elizabeth A. Stone¹. Impacts of co-firing biomass on emissions of particulate matter to the atmosphere. Fuel, Volume 162, 15 December 2015, Pages 111–120.

Show Affiliations

1. Chemistry Department, College of Liberal Arts and Sciences, The University of Iowa, Iowa City, IA 52242, USA
2. Chemistry Department, College of Sciences, University of Basrah, Basrah, Iraq

 

 

Go To Fuel

 

 

Read more research excellence studies on: Renewable Energy Global Innovations (http://ift.tt/21cCPA4)