The present and future energy requirements of mankind can be fulfilled with sustained research and development efforts by global scientists.The purpose of this review paper is to provide an overview of the fundamental...The present and future energy requirements of mankind can be fulfilled with sustained research and development efforts by global scientists.The purpose of this review paper is to provide an overview of the fundamentals,recent advancements on Lithium and non-Lithium electrochemical rechargeable battery systems,and their future prospects.The initial part of this review paper is dedicated to the advancement and challenges faced by the conventional rechargeable batteries,such as lead-acid,Ni-Cd and Ni-MH batteries.The subsequent section of this review focuses on an in-depth analysis of two major categories of rechargeable batteries,namely lithium-based rechargeable battery systems and alternative non-Lithium rechargeable battery systems.The working principle,construction,and a few important research progress on Li-ion,Li-O_(2),Li-CO_(2) and Li-S batteries have been highlighted.The recent progress and challenges of the alternate batteries such as Na-ion,Na-S,Mg-ion,K-ion,Al-ion,Al-air,Zn-ion and Zn-air are also discussed in this review.The large gap between theoretical and practical electrochemical values for the alternate battery system must be filled by adopting a series of design architectures followed by modern instrumentation for developing next-generation batteries in a sustainable and efficient way.展开更多
Bioenergy,currently the largest renewable energy source in the EU(64%of the total renewable energy consumption),has sparked great interest to meet the32%renewable resources for the 2030 bioeconomy goal.The design of i...Bioenergy,currently the largest renewable energy source in the EU(64%of the total renewable energy consumption),has sparked great interest to meet the32%renewable resources for the 2030 bioeconomy goal.The design of innovative cropping systems informed by bioeconomy imperatives requires the evaluate of the effects of introducing crops for bioenergy into conventional crop rotations.This study aimed to assess the impacts of changes in conventional cropping systems in mixed dairy cattle farms redesigned to introduce bioenergy crops either by increasing the biomass production through an increase of cover crops,while keeping main feed/food crops,or by substituting food crops with an increase of the crop rotation length.The assessment is based on the comparison between conventional and innovative systems oriented to feed and biogas production,with and without tillage,to evaluate their agri-environmental performances(biomass production,nitrogen fertilization autonomy,greenhouse gas emissions and biogas production).The result showed higher values in the biogas cropping system than in the conventional and feed ones for all indicators,biomass productivity(27%and20%higher,respectively),nitrogen fertilization autonomy(26%and 73%higher,respectively),methanogenic potential(77%and 41%higher,respectively)and greenhouse gas emissions(15%and 3%higher,respectively).There were no negative impacts of no-till compared to the tillage practice,for all tested variables.The biogas cropping system showed a better potential in terms of agri-environmental performance,although its greenhouse gas emissions were higher.Consequently,it would be appropriate to undertake a multicriteria assessment integrating agri-environmental,economic and social performances.展开更多
As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Neverthe...As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Nevertheless,how to choose the appropriate location for the IPFC converters has not been discussed thoroughly.To solve this problem,this paper proposes a novel location method for IPFC using entropy theory.To clarify IPFC’s impact on system power flow,its operation mechanism and control strategies of different types of serial converters are discussed.Subsequently,to clarify the system power flow characteristic suitable for device location analysis,the entropy concept is introduced.In this process,the power flow distribution entropy index is used as an optimization index.Using this index as a foundation,the power flow transfer entropy index is also generated and proposed for the IPFC location determination study.Finally,electromechanical electromagnetic hybrid simulations based on ADPSS are implemented for validation.These are tested in a practical power grid with over 800 nodes.A modular multilevel converter(MMC)-based IPFC electromagnetic model is also established for precise verification.The results show that the proposed method can quickly and efficiently complete optimized IPFC location and support IPFC to determine an optimal adjustment in the N-1 fault cases.展开更多
“Never doubt that a small group of thoughtful committed citizens can change the world;indeed,it is the only thing that ever has.”-Margaret Mead My partner,Denise Donahue,and I,Simone du Boise,AIA,LEED AP,NCARB are,i...“Never doubt that a small group of thoughtful committed citizens can change the world;indeed,it is the only thing that ever has.”-Margaret Mead My partner,Denise Donahue,and I,Simone du Boise,AIA,LEED AP,NCARB are,in essence,environmentalists.As licensed architects,certified general contractors,and LEED Accredited Professionals,we co-founded Cadmus Environmental Design-Build in spite of our belief that the world doesn’t really need another developer,builder,or architect,but rather because it most certainly needs environmental stewards.We also believe we have both a personal and professional responsibility to utilize our abilities and expertise to“Build A Better Environment.”Our Weatherford Place Community is a living expression of that commitment to comprehensive energy and water conservation,coupled with contributory assets that demand less and deliver more as a community.Our signature solution,the EcoCraft Hybrid^(TM)Home,provides a prescriptive method towards Net Zero Energy results.Our formula factors efficiency,conservation,and CARE(Clean,Alternative,Renewable,Energy)toward a result of zero demand.Synergistic systems and innovations that include passive solar,active solar PV,and solar thermal are key to measurable results and LEED Platinum Certifications.The EcoCraft Hybrid^(TM)Home evolves around a holistic approach that includes:low impact design;utilitarian driven and directed by the local vernacular;passive and active solar integration;engineered systems to enhance conservation measures;and in-situ analysis that integrates the past with the present.Energy efficiency,water conservation,and environmental care inform the design and construction of an artistic,comfortable,easy to care for,and healthy home that enables universal access and age-in-place abilities.Following our specific design and construction directives,all of this is achievable at price points comparable to conventional construction.展开更多
Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic objectives.Long-term retention of mature forest structures at the time of harvestin...Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic objectives.Long-term retention of mature forest structures at the time of harvesting(variable retention)is intended to produce future forest stands that more closely resemble conditions that develop after natural disturbances,thereby maintaining greater diversity of habitats for a variety of organisms.Structure includes features such as live and dead trees representing multiple canopy layers,undisturbed understory vegetation and coarse woody debris.Over the past two decades,variable retention has become common on forest lands in the temperate rainforests of coastal British Columbia(BC)and has been applied to a lesser extent in inland forest types.Our review of studies in BC and in similar forest types in our region indicates that both aggregated and dispersed retention can contribute to biodiversity conservation by providing short-term‘life-boating’habitat for some species and by enhancing the structural characteristics of future stands.For example,greater abundance of species present in the pre-harvest forest have been documented for vegetation,birds,carabid beetles,gastropods,ectomycorrhizal fungi and soil fauna in retention cutblocks compared to clearcuts.There are,however,some negative consequences for timber production such as wind damage to retained trees and reduced growth rates of tree regeneration compared to clearcuts.The authors suggest an adaptive management approach for balancing competing objectives when faced with uncertainty.This includes monitoring the implementation and effectiveness of various strategies for achieving goals.Over two decades of experience applying variable retention harvesting to industrial-scale management of forest lands in BC suggests that it is possible to balance production of wood with biodiversity conservation.展开更多
Variable retention harvesting is a silvicultural system that focuses on retaining key elements of stand structure at the time of logging and is increasingly being used worldwide.We describe the design and establishmen...Variable retention harvesting is a silvicultural system that focuses on retaining key elements of stand structure at the time of logging and is increasingly being used worldwide.We describe the design and establishment of a variable retention harvesting experiment established in the Mountain Ash(Eucalyptus regnans)forests of the Central Highlands of Victoria,south-eastern Australia.The experiment was instigated in 2003,and the work to date has shown that it has environmental benefits for certain groups of small mammals,birds,and vascular plants.The experiment has been integrated with an ongoing long-term monitoring program as well as other experiments such as those in post-fire salvage-logged areas.Collectively,the results of various studies suggest that the potential value of variable retention harvesting extends beyond green-tree logging to post-fire salvage logging environments.We outline some of the challenges in,and new perspectives derived from,implementing and maintaining our experiment.This included difficulties protecting islands from high-intensity post-harvest regeneration burns and threat of declining funding undermining ongoing project viability.A critically important perspective concerns the ecological and economic context in which variable retention harvesting is implemented.In the particular case of Mountain Ash forests,assessments using formal IUCN criteria classify the ecosystem as being Critically Endangered under the Red Listed Ecosystem approach.As a result,Mountain Ash forests are at a high risk of ecosystem collapse.Further logging will increase that risk,making the basis for continued harvesting questionable.In addition,economic analyses suggest that the value of natural assets,like water production,far outweigh the value of the wood products harvested from the Mountain Ash ecosystem,again leading to questions about the viability of ongoing harvesting.We therefore conclude that whilst variable retention harvesting has the potential to contribute to biodiversity conservation in Mountain Ash forests,broader ecological and economic contextual issues(such as the values of competing resources like water yields and the heavily degraded state of the forest)may erode the case for its broader application.展开更多
The main objective of this paper is three-fold.First, to provide an overview of the current status of the power electronics technology, one of the key actors in the upcoming smart grid paradigm enabling maximum power ...The main objective of this paper is three-fold.First, to provide an overview of the current status of the power electronics technology, one of the key actors in the upcoming smart grid paradigm enabling maximum power throughputs and near-instantaneous control of voltages and currents in all links of the power system chain. Second, to provide a bridge between the power systems and the power electronic communities, in terms of their differing appreciation of how these devices perform when connected to the power grid. Third, to discuss on the role that the power electronics technology will play in supporting the aims and objectives of future decarbonized power systems. This paper merges the equipment, control techniques and methods used in flexible alternating current transmission systems(FACTS) and high voltage direct transmission(HVDC) equipment to enable a single, coherent approach to address a specific power system problem, using ‘best of breed’ solutions bearing in mind technical, economic and environmental issues.展开更多
This paper addresses the attuned use of multi- converter flexible alternative current transmission systems (M-FACTS) devices and demand response (DR) to perform congestion management (CM) in the deregulated envi...This paper addresses the attuned use of multi- converter flexible alternative current transmission systems (M-FACTS) devices and demand response (DR) to perform congestion management (CM) in the deregulated environment. The strong control capability of the M- FACTS offers a great potential in solving many of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare (SW) and congestion as network constraint is paid by using concurrently the DR and M-FACTS. A multi-objective problem (MOP) based on the sum of the payments received by the generators for changing their output, the total payment received by DR participants to reduce their load and M-FACTS cost is systematized. For the solution of this problem a nonlinear time-varying evolution (NTVE) based multi-objective particle swarm optimization (MOPSO) style is formed. Fuzzy decision-making (FDM) and technique for order preference by similarity to ideal solution (TOPSIS) approaches are employed for finding the best compromise solution from the set of Pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-varying evolution (MOPSO-NTVE). In a real power system, Azarbaijan regional power system of Iran, comparative analysis of the results obtained from the application of the DR & unified power flow controller (UPFC) and the DR & M-FACTS are presented.展开更多
We investigate the identification problems of a class of linear stochastic time-delay systems with unknown delayed states in this study. A time-delay system is expressed as a delay differential equation with a single ...We investigate the identification problems of a class of linear stochastic time-delay systems with unknown delayed states in this study. A time-delay system is expressed as a delay differential equation with a single delay in the state vector. We first derive an equivalent linear time-invariant(LTI) system for the time-delay system using a state augmentation technique. Then a conventional subspace identification method is used to estimate augmented system matrices and Kalman state sequences up to a similarity transformation. To obtain a state-space model for the time-delay system, an alternate convex search(ACS) algorithm is presented to find a similarity transformation that takes the identified augmented system back to a form so that the time-delay system can be recovered. Finally, we reconstruct the Kalman state sequences based on the similarity transformation. The time-delay system matrices under the same state-space basis can be recovered from the Kalman state sequences and input-output data by solving two least squares problems. Numerical examples are to show the effectiveness of the proposed method.展开更多
基金the Education Department of the Government of Gujarat for providing fellowships under SHODH (Sc Heme of Developing High-Quality Researchresearch,Ref No:2021013725)for researchthe financial support received from Science and Engineering Research Board,Department of Science and Technology,Government of India (CRG/2022/008719)。
文摘The present and future energy requirements of mankind can be fulfilled with sustained research and development efforts by global scientists.The purpose of this review paper is to provide an overview of the fundamentals,recent advancements on Lithium and non-Lithium electrochemical rechargeable battery systems,and their future prospects.The initial part of this review paper is dedicated to the advancement and challenges faced by the conventional rechargeable batteries,such as lead-acid,Ni-Cd and Ni-MH batteries.The subsequent section of this review focuses on an in-depth analysis of two major categories of rechargeable batteries,namely lithium-based rechargeable battery systems and alternative non-Lithium rechargeable battery systems.The working principle,construction,and a few important research progress on Li-ion,Li-O_(2),Li-CO_(2) and Li-S batteries have been highlighted.The recent progress and challenges of the alternate batteries such as Na-ion,Na-S,Mg-ion,K-ion,Al-ion,Al-air,Zn-ion and Zn-air are also discussed in this review.The large gap between theoretical and practical electrochemical values for the alternate battery system must be filled by adopting a series of design architectures followed by modern instrumentation for developing next-generation batteries in a sustainable and efficient way.
基金project“Bioeconomy Demonstrator Network”(“Réseau de sites démonstrateurs IAR”in French)funded from 2015 to 2020 by the European Union(ERDF)the French State(Commissariat Généralàl’Egalitédes Territoires,CGET)the“Hauts-de-France”Regional Council。
文摘Bioenergy,currently the largest renewable energy source in the EU(64%of the total renewable energy consumption),has sparked great interest to meet the32%renewable resources for the 2030 bioeconomy goal.The design of innovative cropping systems informed by bioeconomy imperatives requires the evaluate of the effects of introducing crops for bioenergy into conventional crop rotations.This study aimed to assess the impacts of changes in conventional cropping systems in mixed dairy cattle farms redesigned to introduce bioenergy crops either by increasing the biomass production through an increase of cover crops,while keeping main feed/food crops,or by substituting food crops with an increase of the crop rotation length.The assessment is based on the comparison between conventional and innovative systems oriented to feed and biogas production,with and without tillage,to evaluate their agri-environmental performances(biomass production,nitrogen fertilization autonomy,greenhouse gas emissions and biogas production).The result showed higher values in the biogas cropping system than in the conventional and feed ones for all indicators,biomass productivity(27%and20%higher,respectively),nitrogen fertilization autonomy(26%and 73%higher,respectively),methanogenic potential(77%and 41%higher,respectively)and greenhouse gas emissions(15%and 3%higher,respectively).There were no negative impacts of no-till compared to the tillage practice,for all tested variables.The biogas cropping system showed a better potential in terms of agri-environmental performance,although its greenhouse gas emissions were higher.Consequently,it would be appropriate to undertake a multicriteria assessment integrating agri-environmental,economic and social performances.
基金supported by the Natural Science Foundation of Sichuan Province of China(No.2022NSFSC0262)the Fundamental Research Funds for the Central Universities(No.2022SCU12005).
文摘As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Nevertheless,how to choose the appropriate location for the IPFC converters has not been discussed thoroughly.To solve this problem,this paper proposes a novel location method for IPFC using entropy theory.To clarify IPFC’s impact on system power flow,its operation mechanism and control strategies of different types of serial converters are discussed.Subsequently,to clarify the system power flow characteristic suitable for device location analysis,the entropy concept is introduced.In this process,the power flow distribution entropy index is used as an optimization index.Using this index as a foundation,the power flow transfer entropy index is also generated and proposed for the IPFC location determination study.Finally,electromechanical electromagnetic hybrid simulations based on ADPSS are implemented for validation.These are tested in a practical power grid with over 800 nodes.A modular multilevel converter(MMC)-based IPFC electromagnetic model is also established for precise verification.The results show that the proposed method can quickly and efficiently complete optimized IPFC location and support IPFC to determine an optimal adjustment in the N-1 fault cases.
文摘“Never doubt that a small group of thoughtful committed citizens can change the world;indeed,it is the only thing that ever has.”-Margaret Mead My partner,Denise Donahue,and I,Simone du Boise,AIA,LEED AP,NCARB are,in essence,environmentalists.As licensed architects,certified general contractors,and LEED Accredited Professionals,we co-founded Cadmus Environmental Design-Build in spite of our belief that the world doesn’t really need another developer,builder,or architect,but rather because it most certainly needs environmental stewards.We also believe we have both a personal and professional responsibility to utilize our abilities and expertise to“Build A Better Environment.”Our Weatherford Place Community is a living expression of that commitment to comprehensive energy and water conservation,coupled with contributory assets that demand less and deliver more as a community.Our signature solution,the EcoCraft Hybrid^(TM)Home,provides a prescriptive method towards Net Zero Energy results.Our formula factors efficiency,conservation,and CARE(Clean,Alternative,Renewable,Energy)toward a result of zero demand.Synergistic systems and innovations that include passive solar,active solar PV,and solar thermal are key to measurable results and LEED Platinum Certifications.The EcoCraft Hybrid^(TM)Home evolves around a holistic approach that includes:low impact design;utilitarian driven and directed by the local vernacular;passive and active solar integration;engineered systems to enhance conservation measures;and in-situ analysis that integrates the past with the present.Energy efficiency,water conservation,and environmental care inform the design and construction of an artistic,comfortable,easy to care for,and healthy home that enables universal access and age-in-place abilities.Following our specific design and construction directives,all of this is achievable at price points comparable to conventional construction.
基金by the Province of British Columbia(BC Ministry of Forests,Lands,Natural Resource Operations and Rural DevelopmentBC Forest Investment Account,Land Based Investment ProgramBC Forest Science Program),the University of British Columbia and forest companies(Cascadia Forest Products,MacMillan Bloedel Limited,Western Forest Products Inc.,Weyerhaeuser Company).Other than the scientists and field personnel directly involved in the research,the funding bodies did not have a role in the design of the studies,in the collection,analysis,and interpretation of data,and in writing the manuscript.
文摘Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic objectives.Long-term retention of mature forest structures at the time of harvesting(variable retention)is intended to produce future forest stands that more closely resemble conditions that develop after natural disturbances,thereby maintaining greater diversity of habitats for a variety of organisms.Structure includes features such as live and dead trees representing multiple canopy layers,undisturbed understory vegetation and coarse woody debris.Over the past two decades,variable retention has become common on forest lands in the temperate rainforests of coastal British Columbia(BC)and has been applied to a lesser extent in inland forest types.Our review of studies in BC and in similar forest types in our region indicates that both aggregated and dispersed retention can contribute to biodiversity conservation by providing short-term‘life-boating’habitat for some species and by enhancing the structural characteristics of future stands.For example,greater abundance of species present in the pre-harvest forest have been documented for vegetation,birds,carabid beetles,gastropods,ectomycorrhizal fungi and soil fauna in retention cutblocks compared to clearcuts.There are,however,some negative consequences for timber production such as wind damage to retained trees and reduced growth rates of tree regeneration compared to clearcuts.The authors suggest an adaptive management approach for balancing competing objectives when faced with uncertainty.This includes monitoring the implementation and effectiveness of various strategies for achieving goals.Over two decades of experience applying variable retention harvesting to industrial-scale management of forest lands in BC suggests that it is possible to balance production of wood with biodiversity conservation.
文摘Variable retention harvesting is a silvicultural system that focuses on retaining key elements of stand structure at the time of logging and is increasingly being used worldwide.We describe the design and establishment of a variable retention harvesting experiment established in the Mountain Ash(Eucalyptus regnans)forests of the Central Highlands of Victoria,south-eastern Australia.The experiment was instigated in 2003,and the work to date has shown that it has environmental benefits for certain groups of small mammals,birds,and vascular plants.The experiment has been integrated with an ongoing long-term monitoring program as well as other experiments such as those in post-fire salvage-logged areas.Collectively,the results of various studies suggest that the potential value of variable retention harvesting extends beyond green-tree logging to post-fire salvage logging environments.We outline some of the challenges in,and new perspectives derived from,implementing and maintaining our experiment.This included difficulties protecting islands from high-intensity post-harvest regeneration burns and threat of declining funding undermining ongoing project viability.A critically important perspective concerns the ecological and economic context in which variable retention harvesting is implemented.In the particular case of Mountain Ash forests,assessments using formal IUCN criteria classify the ecosystem as being Critically Endangered under the Red Listed Ecosystem approach.As a result,Mountain Ash forests are at a high risk of ecosystem collapse.Further logging will increase that risk,making the basis for continued harvesting questionable.In addition,economic analyses suggest that the value of natural assets,like water production,far outweigh the value of the wood products harvested from the Mountain Ash ecosystem,again leading to questions about the viability of ongoing harvesting.We therefore conclude that whilst variable retention harvesting has the potential to contribute to biodiversity conservation in Mountain Ash forests,broader ecological and economic contextual issues(such as the values of competing resources like water yields and the heavily degraded state of the forest)may erode the case for its broader application.
基金supported by Spanish Ministry of Economy and Competitiveness and Junta de Andalucía through the projects ENE2014-54115-R and TEP-7411
文摘The main objective of this paper is three-fold.First, to provide an overview of the current status of the power electronics technology, one of the key actors in the upcoming smart grid paradigm enabling maximum power throughputs and near-instantaneous control of voltages and currents in all links of the power system chain. Second, to provide a bridge between the power systems and the power electronic communities, in terms of their differing appreciation of how these devices perform when connected to the power grid. Third, to discuss on the role that the power electronics technology will play in supporting the aims and objectives of future decarbonized power systems. This paper merges the equipment, control techniques and methods used in flexible alternating current transmission systems(FACTS) and high voltage direct transmission(HVDC) equipment to enable a single, coherent approach to address a specific power system problem, using ‘best of breed’ solutions bearing in mind technical, economic and environmental issues.
文摘This paper addresses the attuned use of multi- converter flexible alternative current transmission systems (M-FACTS) devices and demand response (DR) to perform congestion management (CM) in the deregulated environment. The strong control capability of the M- FACTS offers a great potential in solving many of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare (SW) and congestion as network constraint is paid by using concurrently the DR and M-FACTS. A multi-objective problem (MOP) based on the sum of the payments received by the generators for changing their output, the total payment received by DR participants to reduce their load and M-FACTS cost is systematized. For the solution of this problem a nonlinear time-varying evolution (NTVE) based multi-objective particle swarm optimization (MOPSO) style is formed. Fuzzy decision-making (FDM) and technique for order preference by similarity to ideal solution (TOPSIS) approaches are employed for finding the best compromise solution from the set of Pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-varying evolution (MOPSO-NTVE). In a real power system, Azarbaijan regional power system of Iran, comparative analysis of the results obtained from the application of the DR & unified power flow controller (UPFC) and the DR & M-FACTS are presented.
文摘We investigate the identification problems of a class of linear stochastic time-delay systems with unknown delayed states in this study. A time-delay system is expressed as a delay differential equation with a single delay in the state vector. We first derive an equivalent linear time-invariant(LTI) system for the time-delay system using a state augmentation technique. Then a conventional subspace identification method is used to estimate augmented system matrices and Kalman state sequences up to a similarity transformation. To obtain a state-space model for the time-delay system, an alternate convex search(ACS) algorithm is presented to find a similarity transformation that takes the identified augmented system back to a form so that the time-delay system can be recovered. Finally, we reconstruct the Kalman state sequences based on the similarity transformation. The time-delay system matrices under the same state-space basis can be recovered from the Kalman state sequences and input-output data by solving two least squares problems. Numerical examples are to show the effectiveness of the proposed method.