Добірка наукової літератури з теми "Large-scale economic systems"

The paper deals with electric models applied in the investigation of complex systems, such as transport, economic, and neuron systems. The increasing interest in such systems can be explained by the fact that they are characterized by parallel (collective) means of complex calculation processes, under the influence of inner information processes. Electric models can also be looked upon as original structures for neuron-like systems. The paper puts emphasis on comparison between the electric models suggested by the authors, on the one hand, and the mechanical and thermal models, on the other hand. It has been shown that entropy phenomena, typical for the latter, can be closely compared to those of electric models, which are distinguished by pure electric values. Also, it has been shown that irreversible processes of energy dissipation, e.g., entropy processes in mechanical models, are corresponded to processes of energy concentration, energy transfer, and/or energy exchange in electric models. This enables us to shed a new light on processes in electric circuit, especially those concerning with structural improvements of electric circuitry and their self-organization, meaning a neg-entropic information character of these processes. Models of two economic tasks have been considered, wherein the calculation process is characterized under the influence of these processes. Assumption on the importance of reactive elements such as carriers of neg-entropy in electric circuits was made as well.

Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 185-191).
Electricity from solar energy has many favorable attributes. Despite its current high cost relative to other technology options, a combination of cost reductions and policy support measures could lead to increasing deployment of solar power technologies. Should this pathway occur, the unique technical and economic characteristics of photovoltaics (PV) and concentrating solar power (CSP) technology will have implications for the wider electric power system. Similarly, the characteristics of the many elements that constitute electric power systems will have implications for the efficient deployment of these technologies. This thesis attempts to assess these technical and economic implications, and derive regulatory implications that result. A static cost-minimization expansion model with an 8760 hour temporal resolution, adapted from the literature, was developed in order to undertake this investigation. Following analytical development of the model formulation, the model was numerically applied to a simplified representation of the ERCOT power system. This application involved assessing changes in investment, dispatch, prices and emissions across various solar power deployment scenarios. The final portion of the thesis then addressed the complexities associated with developing the necessary transmission that may accompany large-scale solar power deployment. Findings from this work include: a) an explicit representation of the components that constitute the marginal system value of PV capacity under transmission constraints b) reasoning for why the optimal system with large scale solar power capacity includes less baseload capacity in the long term - and insights into how this may not be feasible in real systems, and c) a presentation of how solar power deployment paths diverge across capacity and energy support schemes, and across type of solar technology. In addition, it is found that: d) under perfect conditions, locational market prices will provide the adequate locational signals for `system-ecient' deployment, provided that the solar generators 'see' the signals in their objective functions, and e) the appropriateness of transmission charges for solar generators will vary by circumstance - any charge warranted should be considered in tandem with the system pricing mechanism and any renewable support scheme in place.
by James Hubert Merrick.
S.M.
S.M.in Technology and Policy

Non-centralized control schemes for large-scale systems, including energy networks, are more flexible, scalable, and reliable than the centralized counterpart. These benefrts are obtained by having a set of local control!ers, each of which is responsible for a partition of the system, instead of one central entity that controls the whole system. Furthermore,in sorne cases, employing a non­ centralized control structure might be necessary due to the intractability problem of the centralized method.Thus, this thesis is devoted to the study of non-centralized optimization-based control approaches for large-scale energy systems. Mainly,this thesis focuses on the communication and cooperation processes of local controllers, which are integral parts of such schemes. Throughout this thesis,the model predictíve control framework is applied to solve the economic dispatch problem of large-scale energy systems. In a non-centralized architecture, local controllers must cooperatively solve the economic dispatch problem, which is formulated as a convex optimization problem with edge-based coupling constraints, at each time step.Therefore, first, the augmented Lagrangian approach is deployed to decompose the problem and to design two distributed optimization methods, which are iterative and require the local controllers to exchange information with each other at each iteration. lt is then shown that the sequence produced by these methods converges to an optima!solution when sorne cond tions, which include how the controllers must communicate and cooperate, are satisfied. However, in practice, the communication process might not always be perfect,i.e.,the required communication assumption does not hold. In the case of communication link failures, the distributed methods might not be able to compute a solution.Therefore,an information exchange protocol that is based on consensus is designed to overcome this problem. Furthermore, the proposed distributed methods are also further·extended such that they work over random communication networks and asynchronous updates, i.e.,when not all controllers always perform the updates . Under this setup, the convergence and the convergence rate of the algorithms are shown. Additionally, the implementation of these distributed methods to an MPC-based economic dispatch is also presented. The discussion includes the techniques that can be used to reduce the number of iterat ions and the performance of the methods in a numerical study. Considering that the aforementioned methods are comrnunication-intensive, an alternative non-centralized scheme, which provides a trade-off between comrnunication intensity and suboptirnality,is proposed.The scheme consists of repartitioning the network online with the aim of obtaining self-sufficient subsystems, forming coalitions for subsystems that are not self-sufficient,and decomposing the economic dispatch problem of the system into coalition-based subproblems. In this scheme, each subsystem only communicates to the others that belong to the sarne coalition;thus, reducing communication. Especially when all subsystems are self-sufficient, exchanging information is not needed. Finally,a cooperation problem during the implementation of the decisions is discussed. Specifically, sorne subsystems do not cornply with the computed decisions to gain better performance at the cost of deteriorating the performance of the other subsystems.A resilient scheme that can cope with this problem is formulated.lt consists of a stochastic method to robustify the decisions against such adversaria! behavior and an identification and mitigation method that is based on hypothesis testing using Bayesian inference.The proposed scheme, in general,can mitigate the effect of non-
Los esquemas de control no centralizados aplicados a sistemas a gran escala, entre los que se incluyen las redes energéticas, son más flexibles, escalables y fiables que sus equivalentes centralizados. Dichos beneficios pueden obtenerse empleando un conjunto de controladores locales, donde cada uno de ellos es responsable de una parte del sistema, en lugar de una entidad central que controle la totalidad del sistema.Asimismo,el uso de una estructura de control no centralizada podría ser, en algunos casos, necesario, dado el problema de intratabilidad del método centralizado. Por consiguiente, la presente tesis trata sobre el estudio de enfoques de control no centralizados basados en optimización para redes energéticas a gran escala. Principalmente, esta tesis se centra en los procesos de comunicación y cooperación llevados a cabo por los controladores locales , que constituyen partes esenciales de dichos esquemas . A lo largo de esta tesis, el control predictivo basado en modelos se usa para resolver el problema de expedir energia en redes energéticas a gran escala desde un punto de vista económico. En arquitecturas no centralizadas, los controladores locales deben resolver dicho problema de forma cooperativa, el cual se formula como un problema de optimización convexo con restricciones de acoplamiento en los enlaces entre nodos, que debe ser resuelto en cada instante de tiempo. Para ello, el método de Lagrangiano aumentado se utiliza inicialmente para descomponer el problema y diseñar dos métodos de optimización distribuidos , que son iterativos y requieren que los controladores locales intercambien información entre ellos en cada iteración . A continuación, se muestra que la secuencia generada por estos métodos converge a la solución óptima a condición de que se cumplan ciertas condiciones,incluyendo cómo los controladores deben comunicarse y cooperar. Sin embargo, en la práctica,la comunicación no siempre es perfecta, es decir,el supuesto de comunicación requerido no se cumple. En el caso de fallos en los enlaces de comunicación, los métodos distribuidos podrían no ser capaces de proporcionar una solución. Para paliar este problema, se diseña un protocolo de información basado en consenso.l'v1ás aún, los métodos de optimización distribuidos se extienden a fin de que sean capaces de trabajar en redes con comunicaciones aleatorias y actualizaciones asíncronas, es decir,redes en que no todos los controladores realicen las actualizaciones . En esta configuración se muestran la convergencia y el orden de convergencia de dichos algoritmos. Se muestra, además, la implementación de estos métodos en el control predictivo económico basado en modelos para redes energéticas. La discusión incluye las técnicas que pueden usarse para reducir el número de iteraciones, así como el desempeño de los métodos, a través de un estudio numérico. Teniendo en cuenta que los métodos anteriormente mencionados requieren una comunicación intensa,se propone otro esquema no centralizado que proporciona un compromiso entre intensidad de comunicación y suboptimalidad . Dicha estrategia consiste en volver a particionar en línea el sistema con el objetivo de obtener subsistemas autosuficientes,formando coaliciones de subsistemas que no lo sean por separado,y descomponiendo el problema económico de expedición de energía en subproblemas de tipo coalicional. En este esquema ,cada subsistema se comunica únicamente con aquellos otros subsistemas que pertenezcan a la misma coalición, reduciendo asi el tráfico de comunicación. En particular, cuando todos los subsistemas son autosuficientes, el intercambio de información ya no es necesario. Finalmente,se considera el problema de la cooperación durante la implementación de las decisiones Específicamente, algunos subsistemas no acatan las decisiones tomadas con el fin de lograr un desempeño propio superior a expensas de empeorar el desempeño de otros subsistemas. Es por esto que, con el fin de lidiar con este problema, se propone un esquema resiliente, el cual consiste en un método estocástico para hacer las decisiones más robustas frente a tal comportamiento adverso, y un método de identificación y mitigación basado en evaluación de hipótesis usando inferencia bayesiana. En general, el esquema propuesto logra mitigar el efecto de los subsistemas incumplidores sobre el resto, y en un caso concreto, también permite identificar los subsistemas adversos.
Els esquemes de control no centralitzats aplicats a sistemes a gran escala, entre els quals s’inclouen les xarxes energètiques, són més flexibles, escalables i fiables que els seus equivalents centralitzats. Aquests beneficis es poden obtenir fent servir un conjunt de controladors locals, en què cadascun d’ells és responsable d’una part del sistema, en lloc d’una entitat central que controli la totalitat del sistema. Així mateix, l’ús d’una estructura de control no centralitzada podria ser, en alguns casos, necessari, donat el problema d’intractabilitat del mètode centralitzat. Per tant, la present tesi tracta sobre l’estudi d’enfocaments de control no centralitzats basats en optimització per a xarxes energètiques a gran escala. Principalment, aquesta tesi se centra en els processos de comunicació i cooperació duts a terme pels controladors locals, que constitueixen parts essencials d’aquests esquemes. Al llarg d’aquesta tesi, el control predictiu basat en models s’utilitza per a resoldre el problema d’expedició d’energia en xarxes energètiques a gran escala des d’un punt de vista econòmic. En arquitectures no centralitzades, els controladors locals han de resoldre aquest problema de forma cooperativa, formulat com un problema d’optimització convex amb restriccions d’acoblament en els enllaços entre nodes i que ha de ser resolt a cada instant de temps. A tal efecte, el mètode de Lagrangià augmentat s’utilitza inicialment per a descomposar el problema i dissenyar dos mètodes d’optimització distribuïts, que són iteratius i requereixen que els controladors locals intercanviïn informació entre ells a cada iteració. A continuació, es mostra que la seqüència generada per aquests mètodes convergeix a la solució òptima si es compleixen certes condicions, incloent la manera en què els controladors s’han de comunicar i cooperar. No obstant això, a la pràctica, la comunicació no és sempre perfecta, és a dir, el supòsit de comunicació perfecta no es compleix. En el cas de fallades en els enllaços de comunicació, els mètodes distribuïts podrien no ser capaços de proporcionar una solució. Per a resoldre aquest problema, es dissenya un protocol d’informació basat en consens. A més, els mètodes d’optimització distribuïts s’amplien per tal que siguin capaços de treballar en xarxes amb comunicacions aleatòries i actualitzacions asíncrones, és a dir, xarxes en què no tots els controladors realitzin les actualitzacions. En aquestes configuracions es mostren la convergència i l’ordre de convergència d’aquests algoritmes. A més, es mostra també la implementació d’aquests mètodes en el control predictiu econòmic basat en models per a xarxes energètiques. La discussió inclou les tècniques que es poden emprar per a reduir el nombre d’iteracions, així com el rendiment dels mètodes, fent servir un estudi numèric. Tenint en compte que els mètodes anteriorment esmentats requereixen una comunicació intensa, es proposa un altre esquema no centralitzat que proporciona un compromís entre intensitat de comunicació i suboptimalitat. Aquesta estratègia consisteix en tornar a particionar el sistema en línia amb l’objectiu d’obtenir subsistemes autosuficients, formant coalicions de subsistemes que no ho siguin per separat, i descomposant el problema econòmic d’expedició d’energia en subproblemes de tipus coalicional. En aquest esquema, cada subsistema es comunica únicament amb aquells altre subsistemes que pertanyin a la mateixa coalició, reduint així el trànsit de comunicació. En particular, quan tots els sistemes són autosuficients, l’intercanvi d’informació deixa de ser necessari. Finalment, es considera el problema de la cooperació durant la implementació de les decisions. Específicament, alguns subsistemes no acaten les decisions preses amb la finalitat de millorar el propi rendiment a costa de disminuir el d’altres subsistemes. És per això que, a fi de solucionar aquest problema, es proposa un esquema resilient, el qual consisteix en un mètode estocàstic per fer les decisions més robustes davant d’aquest comportament advers, i un mètode d’identificació i mitigació basat en evaluar hipòtesis utilitzant inferència bayesiana. En general, l’esquema proposat aconsegueix mitigar l’efecte que els subsistemes no obedients exerceixen sobre la resta, i en un cas concert, també permet identificar els subsistemes adversos.
ABSTRAKSI (Indfonesian) Skema kendali yang tidak tersentralisasi untuk sistem berskala besar, seperti sistem aringan energi, lebih fleksibel, skalabel, dan reliabel dibandingkan dengan skema tersentralisasi. Keuntungan ini diperoleh dari terdapatnya satu set pengendali lokal, yang hanya bertanggung jawab terhadap satu partisi dari sistem tersebut, daripada jika hanya terdapat satu entitas yang mengendalikan seluruh sistem. Bahkan dalam beberapa sistem, penerapan struktur kendali yang tidak tersentralisasi menjadi keharusan karena adanya permasalahan intraktabilitas dari metode tersentralisasi. Oleh karena itu, disertasi ini bertujuan untuk melakukan studi pada metode kendali berdasarkan optimisasi dengan struktur yang tidak tersentralisasi untuk sistem energi berskala besar. Khususnya, disertasi ini memfokuskan pada proses komunikasi dan kooperasi pengendali‐pengendali lokal, yang merupakan bagian integral dalam skema yang dimaksud. Pada disertasi ini, sistem kontrol prediktif (model predictive control (MPC)) diterapkan untuk menyelesaikan optimisasi economic dispatch pada sistem energi berskala besar. Dalam arsitektur yang tidak tersentralisasi, pengendali‐pengendali lokal harus menyelesaikan permasalahan economic dispatch secara kooperatif. Permasalahan economic dispatch ini diformulasikan sebagai optimisasi yang konveks dan memiliki konstrain terkopling. Oleh karena itu, pendekatan Lagrange yang teraugmentasi diterapkan untuk mendekomposisi permasalahan optimisasi terkait. Pendekatan ini juga digunakan untuk merancang dua metode optimisasi terdistribusi, yang iteratif dan mengharuskan pengendali‐pengendali lokal bertukar informasi satu sama lain pada setiap iterasi. Sekuensi yang dihasilkan dari kedua metode tersebut akan terkonvergensi pada suatu solusi yang optimal apabila beberapa kondisi, yang meliputi bagaimana pengendali harus berkomunikasi dan berkooperasi, terpenuhi. Namun, pada praktiknya, proses komunikasi yang terjadi mungkin tidak selalu sempurna, dalam hal ini asumsi pada proses komunikasi yang dibutuhkan tidak terpenuhi. Pada kasus kegagalan jaringan komunikasi, metode terdistribusi yang dirancang mungkin tidak dapat menemukan solusinya. Oleh karena itu, suatu protokol untuk pertukaran informasi yang berdasarkan pada konsensus dirancang untuk mengatasi permasalahan ini. Selanjutnya, dua metode terdistribusi yang telah dirancang juga dikembangkan lebih jauh sehingga metode‐metode tersebut dapat bekerja pada jaringan komunikasi stokastik dengan proses yang asinkron, yaitu proses dimana tidak semua pengendali selalu melakukan pembaruan. Dalam hal ini, konvergensi dan laju konvergensi dari metode yang dirancang dipertunjukkan. Selain itu, implementasi dari metode terdistribusi pada sistem economic dispatch berbasis MPC juga dibahas. Diskusi pada bagian ini mencakup beberapa teknik yang dapat digunakan untuk mengurangi jumlah iterasi dan performa dari metode‐metode yang dirancang pada suatu studi numerik. Dengan pertimbangan bahwa metode‐metode yang disebut sebelumnya membutuhkan komunikasi yang intensif, maka sebuah skema alternatif, yang memberikan trade‐off antara intensitas komunikasi dan suboptimalitas, juga dirancang. Skema ini terdiri dari repartisi sistem online yang bertujuan untuk mendapatkan subsistemsubsistem yang swasembada, pembentukan koalisi untuk subsistem‐subsistem yang tidak swasembada, dan dekomposisi permasalahan economic dispatch menjadi subproblem berbasis koalisi. Dalam skema ini, tiap subsistem hanya perlu berkomunikasi dengan subsistem‐subsistem lain yang berada pada koalisi yang sama; sehingga mengurangi aliran komunikasi. Jika semua subsistem yang terbentuk swasembada, maka pertukaran informasi tidak dibutuhkan sama sekali. Pada akhirnya, disertasi ini juga membahas mengenai suatu permasalahan koperasi dalam masa implementasi keputusan (solusi). Pada permasalahan kooperasi ini, terdapat beberapa subsistem yang tidak menuruti keputusan (solusi), misalnya dengan tujuan untuk mendapatkan kinerja yang lebih baik dan di saat yang bersamaan memperburuk kinerja subsistem lainnya. Maka, sebuah skema resilien yang dapat mengatasi permasalahan ini dirumuskan. Skema tersebut terdiri dari sebuah metode stokastik untuk merobustifikasi keputusan terhadap perilaku adversari dan sebuah metode identifikasi dan mitigasi yang berdasarkan pada pengujian hipotesis dengan menggunakan inferensi Bayes. Skema yang diusulkan, secara umum, dapat memitigasi pengaruh subsistem yang tidak patuh pada subsistem reguler, dan pada kasus tertentu, juga dapat mengidentifikasi subsistem yang menjadi adversari.

У статі визначено необхідність вдосконалення системи управління організаційно-економічним механізмом забезпечення ефективної організації та стійкого організаційного розвитку підприємства; наведено переваги великомасштабних економічних систем перед іншими організаційними формами; розглянуто поняття "розвиток" та модель життєвого циклу великомасштабних економічних систем.
The article defines the necessity of improving the management system of the organizational and economic mechanism for ensuring an effective organization and sustainable organizational development of the enterprise; also there were presented advantages of large-scale economic systems over other organizational forms; the concept of "development" and the life cycle model of large-scale economic systems are considered.

This dissertation deals with some computational and analytic challenges for dynamic process operations using first-principles models. For processes with significant spatial variations, spatially distributed first-principles models can provide accurate physical descriptions, which are crucial for offline dynamic simulation and optimization. However, the large amount of time required to solve these detailed models limits their use for online applications such as nonlinear model predictive control (NMPC). To cope with the computational challenge, we develop computationally efficient and accurate dynamic reduced order models which are tractable for NMPC using temporal and spatial model reduction techniques. Then we introduce an input and state blocking strategy for NMPC to further enhance computational efficiency. To improve the overall economic performance of process systems, one promising solution is to use economic NMPC which directly optimizes the economic performance based on first-principles dynamic models. However, complex process models bring challenges for the analysis and design of stable economic NMPC controllers. To solve this issue, we develop a simple and less conservative regularization strategy with focuses on a reduced set of states to design stable economic NMPC controllers. In this thesis, we study the operation problems of a solid sorbent-based CO2 capture system with bubbling fluidized bed (BFB) reactors as key components, which are described by a large-scale nonlinear system of partial-differential algebraic equations. By integrating dynamic reduced models and blocking strategy, the computational cost of NMPC can be reduced by an order of magnitude, with almost no compromise in control performance. In addition, a sensitivity based fast NMPC algorithm is utilized to enable the online control of the BFB reactor. For economic NMPC study, compared with full space regularization, the reduced regularization strategy is simpler to implement and lead to less conservative regularization weights. We analyze the stability properties of the reduced regularization strategy and demonstrate its performance in the economic NMPC case study for the CO2 capture system.

The objective of this thesis was to investigate the potential for introducing a concentrating solar thermal (CST) central receiver plant system based on flexible heliostats - HelioPods - to provide high-temperature process heat in industrial applications. A CST plant system was designed in MATLAB, optically simulated for three design days in the ray-tracing software Tonatiuh and further analyzed in MATLAB by interpolating the results for each hour of the year. A case study was made on introducing a CST plant system based on HelioPods in a South African manganese sinter plant. The study included an investigation of the profitability of up- and downsizing the heliostat field annually with fluctuating heat demand. A circular heliostat field was modelled for the chosen location. The final field had a radius of 53 meters with the receiver located 60% from the field centre. The storage size was 16 demand hours and 17 plants were required. The results showed that 88% of the annual heat demand could be covered by solar heat in the design year. The marketing approach used for the following years was that the heat demand covered by solar heat should never be below the share at the first year, despite the predicted fluctuations in demand. Thus, a minimum solar share of 88% was used as a strategy for annual up- and downsizing of the fields throughout the investigated period of 25 years. That resulted in a field radius differing between 52 and 55 meters. The payback period of the final system was 4.35 years, the NPV was 54.33 MUSD over a period of 25 years and the LCOH was 35.39 USD/MWht. However, it was found that the profitability of the system was sensitive to the different scenarios for predicted future diesel prices, this since the pricing of the solar heat was set to 90% of the diesel price. The results in this thesis show that a CST plant system based on HelioPods is a suitable solution to supply high-temperature process heat to industrial applications. It also shows that the HelioPods can unlock potential for flexibility with changing production patterns in the industry of implementation. The results from the study can be used also for other industries with similar temperature range and heat demand. Thus, it could be argued that the implementation of a HelioPod based CST plant system also can be suitable for other industries located in high-DNI areas with dependency on conventional fuels and steady production throughout the whole day.
Syftet med denna uppsats var att undersöka potentialen för implementering av koncentrerad termisk solvärme (CST) från ett soltorn med ett heliostatfält baserat på flexibla heliostater - HelioPods – för att generera högtempererad processvärme för industriell tillämpning. Ett CST-system designades i MATLAB, simulerades för tre designdagar i det optiska ray-tracingprogrammet Tonatiuh och analyserades sedan åter i MATLAB genom att interpolera de genererade resultaten för årets alla timmar. En fallstudie av ett CST-system baserat på HelioPods i ett sydafrikanskt sinterverk för mangan genomfördes därefter. Studien innehöll en undersökning av lönsamheten av årlig ökning och minskning av heliostatfältet vid fluktuerande värmebehov. Ett cirkulärt heliostatfält modellerades för den valda platsen. Det slutgiltiga fältet hade en radie om 53 meter med mottagaren placerad 60% från fältets mittpunkt. Storleken på lagringsfaciliteten var 16 timmar av full tillförsel och antalet verk uppgick till 17. Resultaten visade att 88% av det årliga värmebehovet kunde förses med solvärme under designåret. Marknadsstrategin för de resterande åren var att den procentuella andelen solvärme aldrig skulle vara lägre än under designåret, oberoende av fluktuationer i värmebehovet på grund av ändrad produktion. Således sattes 88% solvärme som ett minimikrav och utgjorde strategin för den årliga ökningen och minskningen av fältet för den undersökta perioden av 25 år. Det resulterade i en fältradie mellan 52 och 55 meter. Återbetalningstiden för det slutgiltiga fältet var 4.35 år, nuvärdesberäkningen av det framtida kassaflödet var 54.22 miljoner USD över en 25-årsperiod och produktionskostnaden för värme (LCOH) var 35.39 USD/MWht. Dock var systemets lönsamhet känslig för de olika prognoser av framtida dieselpriser som undersöktes, detta eftersom priset för solvärme sattes till 90% av dieselpriset. Resultaten i denna uppsats visar att ett CST-system baserat på HelioPods är en lämplig lösning för att generera högtempererad processvärme för industriell tillämpning. De visar även att HelioPods kan öka potentialen för flexibilitet vid förändringar i produktionsmönstret i vederbörande industri. Resultaten kan även användas i andra industrier med likartade temperaturer och värmebehov. Hävdas kan således att implementation av ett CST-system kan vara lämpligt även för andra industrier belägna i områden med högt DNI som är beroende på konventionella energikällor och har jämn produktion dygnet runt.

This thesis centres on issues of economic efficiency originating from the large-scale development of intermittent renewable energy sources (RES) in Europe. The flexible resources that are necessary to cope with their specificities (variability, low-predictability, site specificity) are already known, but adequate signals are required to foster efficient operation and investment in these resources. A first question is to what extent intermittent RES can remain out of the market at times when they are the main driver of investment and operation in power systems. A second question is whether the current market design is adapted to their specificities. These two questions are tackled in four distinct contributions.The first chapter is a critical literature review. This analysis introduces and confronts two (often implicit) paradigms for RES integration. It then identifies and discusses a set of evolutions required to develop a market design adapted to the large-scale development of RES, such as new definitions of the products exchanged and reorganisation of the sequence of electricity markets.In the second chapter, an analytical model is used to assess the potential of intraday markets as a flexibility provider to intermittent RES with low production predictability. This study highlights and demonstrates how the potential of intraday markets is heavily dependent on the evolution of the forecast errors.The third chapter focuses on the benefits of curtailing the production by intermittent RES, as a tool to smooth out their variability and reduce overall generation costs. Another analytical model is employed to anatomize the relationship between these benefits and a set of pivotal parameters. Special attention is also paid to the allocation of these benefits between the different stakeholders.In the fourth chapter, a numerical simulation is used to evaluate the ability of the European transmission system operators to tackle the investment wave required in order to manage the production of intermittent RES. Alternative financing strategies are then assessed. The findings reveal that under the current trend of tariffs, the volumes of investment forecasted will be highly challenging for transmission system operators.

Les exigences croissantes sur l'efficacité énergétique des bâtiments, l'évolution du {marché} énergétique, le développement technique récent ainsi que les particularités du poste de chauffage ont fait du MPC le meilleur candidat pour la régulation thermique des bâtiments à occupation intermittente. Cette thèse présente une méthodologie basée sur la commande prédictive distribuée visant un compromis entre l'optimalité, la simplicité et la flexibilité de l'implantation de la solution proposée. Le développement de l'approche est progressif : à partir du cas d'une seule zone, la démarche est ensuite étendue au cas multizone et / ou multisource, avec la prise en compte des couplages thermiques entre les zones adjacentes. Après une formulation quadratique du critère MPC pour mieux satisfaire les objectifs économiques du contrôle, la formulation linéaire est retenue. Pour répartir la charge de calcul, des méthodes de décomposition linéaire (comme Dantzig-Wolfe et Benders) sont employées. L'efficacité des algorithmes distribués proposés est illustrée par diverses simulations
The increasing requirements on energy efficiency of buildings, the evolution of the energy market, the technical developments and the characteristics of the heating systems made of MPC the best candidate for thermal control of intermittently occupied buildings. This thesis presents a methodology based on distributed model predictive control, aiming a compromise between optimality, on the one hand, and simplicity and flexibility of the implementation of the proposed solution, on the other hand. The development of the approach is gradually. The mono-zone case is initially considered, then the basic ideas of the solution are extended to the multi-zone and / or multi-source case, including the thermal coupling between adjacent zones. Firstly we consider the quadratic formulation of the MPC cost function, then we pass towards a linear criterion, in order to better satisfy the economic control objectives. Thus, linear decomposition methods (such as Dantzig-Wolfe and Benders) represent the mathematical tools used to distribute the computational charge among the local controllers. The efficiency of the distributed algorithms is illustrated by simulations

AbstractThis chapter takes a deep dive into the practice of transformative change. It suggests that transformation literacy needs to incorporate the understanding that achieving the vision of vital and regenerative systems requires actors to drive change that models the future systems aliveness. Only then can they become successful transformation systems. Practical experience gives evidence that the shift to transformative impact happens best in enlivening networks across systems, in what is called transformation networks. This chapter shows that a necessary systemic perspective on transformation network means they can and need to be strategically built. It introduces six transformation networkenablers that support such strategic guidance in building networks, that were used in two practical examples of setting up transformation networks. The first example is on the local level and looks at a network of youth civil society for good governance in central Tunisia. The second example is on the other end of the spectrum: it examines a global network of professionals towards a new economic future.

AbstractIn education, the ‘Nordic model’ refers to the similarities and shared aims of the education systems developed in the five Nordic countries—Denmark, Finland, Iceland, Sweden and Norway—after World War II. Traditionally, there have always been many similarities and links between the Nordic countries through their historical connections and geographical proximity. The common experience of solidarity and political oppression during World War II also created the basis for a common political orientation in the postwar period, which was also reflected in the education systems during the development of the countries’ economies and their establishment of welfare states. At the same time, this very process has been strongly supported by social-democratic governance in these countries in the 1960s and 1970s (Blossing, Imsen, & Moos, 2014). The model is based on a concept ofEducation for All, where equity, equal opportunities and inclusion are consistently cited as the goal of schooling and orientation (Blossing et al., 2014; Telhaug, Mediås, & Aasen, 2006). This corresponds to the egalitarian idea of a classless society, which is characterised by individual democratic participation, solidarity and mutual respect and appreciation for all. This idea was manifested in, for example, major reallocations of economic resources through the tax systems and free schooling for all, which arose out of the principle that parents’ lack of economic resources should not prevent children from obtaining a good quality education. The equalisation of structural inequalities and creation of equity was—and still is—the task of the education system in the Nordic countries. Worldwide, especially within the Nordic countries, the view is being shared that the education system should be fair and provide access and opportunities for further education, regardless of where someone lives, the status of the parental home, where someone comes from, what ethnic background someone has, what age or gender someone is, what skills one has or whether someone has physical disabilities (Blossing et al., 2014; Quaiser-Pohl, 2013). Some special features of the Nordic system are therefore deeply embedded in the school culture in the countries, for example, through the fact that access to free and public local schools and adapted education is statutory, which is in contrast to many other countries, even other European ones (further developed and discussed in Chap.10.1007/978-3-030-61648-9_2). The Nordic model is widely considered a good example of educational systems that provide equal learning opportunities for all students. Achieving equity, here meaning the creation of fairness, is expressed concretely in political measures to distribute resources equally and strengthen the equality of marginalised groups by removing the barriers to seize educational opportunities, for example, when mixed-ability comprehensive schools are created or the educational system is made inclusive regarding students with special needs (UNESCO, 1994; Wiborg, 2009). Equality is roughly connoted with ‘sameness in treatment’ (Espinoza, 2007), while equity takes further in consideration also the question of how well the requirements of individual needs are met. Thus, the goal of equity is always linked to the concept of justice, provided that an equality of opportunities is created. If, however, one looks at individual educational policy decisions on the creation of educational justice in isolation, one must weigh which concept of equity or equality is present in each case. For example, it is not enough to formally grant equal rights in the education system to disadvantaged groups, but something must also be done actively to ensure that marginalised groups can use and realise this equality. The complexity of the terms becomes even greater when one considers that to achieve equality, measures can be taken that presuppose an unequal distribution of resources or unequal treatment and, therefore, are not fair e.g., when resources are bundled especially for disadvantaged groups and these are given preferential treatment (will be further developed and discussed in Chap.10.1007/978-3-030-61648-9_2). Thus, equality and equity rely on each other and are in a field of tension comprising multiple ideas (Espinoza, 2007).

Harmful algal blooms (HABs) continue to affect lakes and waterways across the nation, often resulting in environmental and economic damage at regional scales. The US Army Engineer Research and Development Center (ERDC) and collaborators have continued research on the Harmful Algal Bloom Interception, Treatment, and Transformation System (HABITATS) project to develop a rapidly deployable and scalable system for mitigating large HABs. The second year of the project focused on optimization research, including (1) development of a new organic flocculant formulation for neutralization and flotation of algal cells; (2) testing and initial optimization of a new, high-throughput biomass dewatering system with low power requirements; (3) development, design, assembly, and initial testing of the first shipboard HABITATS prototype; (4) execution of two field pilot studies of interception and treatment systems in coordination with the Florida Department of Environmental Protection and New York State Department of Environmental Conservation; (5) conversion of algal biomass into biocrude fuel at pilot scale with a 33% increase in yield compared to the previous bench scale continuous-flow reactor studies; and (6) refinement of a scalability analysis and optimization model to guide the future development of full-scale prototypes.

This paper examines renewable energy developments on Aboriginal lands in North-West Western Australia at three scales. It first examines the literature developing in relation to large scale renewable energy projects and the Native Title Act (1993)Cwlth. It then looks to the history of small community scale standalone systems. Finally, it examines locally adapted approaches to benefit sharing in remote utility owned networks. In doing so this paper foregrounds the importance of Aboriginal agency. It identifies Aboriginal decision making and economic inclusion as being key to policy and project development in the 'scaling up' of a transition to renewable energy resources in the North-West.

The Smart Energy Design Assistance Center assessed the administrative, technical, and economic aspects of feasibility related to the procurement and installation of photovoltaic solar systems on IDOT-owned buildings and lands. To address administrative feasibility, we explored three main ways in which IDOT could procure solar projects: power purchase agreement (PPA), direct purchase, and land lease development. Of the three methods, PPA and direct purchase are most applicable for IDOT. While solar development is not free of obstacles for IDOT, it is administratively feasible, and regulatory hurdles can be adequately met given suitable planning and implementation. To evaluate IDOT assets for solar feasibility, more than 1,000 IDOT sites were screened and narrowed using spatial analytic tools. A stakeholder feedback process was used to select five case study sites that allowed for a range of solar development types, from large utility-scale projects to small rooftop systems. To evaluate financial feasibility, discussions with developers and datapoints from the literature were used to create financial models. A large solar project request by IDOT can be expected to generate considerable attention from developers and potentially attractive PPA pricing that would generate immediate cash flow savings for IDOT. Procurement partnerships with other state agencies will create opportunities for even larger projects with better pricing. However, in the near term, it may be difficult for IDOT to identify small rooftop or other small on-site solar projects that are financially feasible. This project identified two especially promising solar sites so that IDOT can evaluate other solar site development opportunities in the future. This project also developed a web-based decision-support tool so IDOT can identify potential sites and develop preliminary indications of feasibility. We recommend that IDOT begin the process of developing at least one of their large sites to support solar electric power generation.

Qualified teachers are a fundamental input for any education system. Yet, many countries struggle to attract highly skilled applicants to the teaching profession. This paper presents the results of a large-scale intervention to attract high performing high-school students into the teaching profession in Chile. The intervention was a three-arm email campaign which made salient three types of motivations typically associated with the teaching profession: intrinsic/altruistic, extrinsic, and prestige-related. The objective was to identify which type of message better appealed to high performing students to nudge them to choose a teaching major. The “intrinsic” and “prestige” arms reduced applications to teaching majors among high performers, while the “extrinsic” arm increased applications among low performers. A plausible interpretation could be that the “intrinsic” and “prestige” messages made more salient an issue that could otherwise be overlooked by high performing students (typically from more advantaged households), negatively impacting their program choice: that while the social value of the teaching profession has improved, it still lags behind other professions that are valued more by their families and social circles. In turn, the “extrinsic” arm made salient the recent improvements in the economic conditions of the teaching profession in Chile, thus appealing to low performing students who in general come from disadvantaged families and for whom monetary incentives are potentially more relevant. These results emphasize the importance of having a clear picture of the inherent motivations that could influence individuals career choice. Making salient certain types of motivations to the wrong target group could lead to undesired results.

Oxfam has been part of the global Fair Trade movement since its inception. Today, it still inspires many of our volunteers to champion just and sustainable trade. Together, we reach out to small-scale producers, workers, and grassroots social entrepreneurs. We partner with activists, communities, democratically governed producer organizations, mission-driven enterprises, and social movements to establish ethical trade approaches and advocate for a more just trade system. We believe the current trade system is far from just or sustainable. It was captured by imperialistic and colonialist forces in the past and remains, even today, under the control of the powerful and the rich to a large extent. Trade justice offers an alternative approach: one that requires shared responsibility according to everyone’s capabilities and considers (historical) privileges, as well as systemic change in the economic, gender, climate and political realms. As long as it excludes people and future generations from its welfare-creating properties, trade cannot be considered just or sustainable.