This dissertation explores the potential of renewable energy and efficiency strategies to solve the energy challenges faced by the people living in the biosphere reserve of El Vizcaíno, which is located in the North Pacific region of the Mexican state of Baja California Sur. This research setting provides a practical analytical milieu to understand better the multiple problems faced by practitioners and agencies trying to implement sustainable energy solutions in Mexico. The thesis starts with a literature review (chapter two) that examines accumulated international experience regarding the development of renewable energy projects as a prelude to identifying the most salient implementation barriers impeding this type of initiatives. Two particularly salient findings from the literature review include the importance of considering gender issues in energy analysis and the value of using participatory research methods. These findings informed fieldwork design and the analytical framework of the dissertation. Chapter three surveys electricity generation as well as residential and commercial electricity use in nine coastal communities located in El Vizcaíno. Chapter three summarizes the fieldwork methodology used, which relies on a mix of qualitative and quantitative research methods that aim at enabling a gender-disaggregated analysis to describe more accurately local energy uses, needs, and barriers. Chapter four describes the current plans of the state government, which are focused in expanding one of the state’s diesel-powered electricity grids to El Vizcaíno. The Chapter also examines the potential for replacing diesel generators with a combination of renewable energy systems and efficiency measures in the coastal communities sampled. Chapter five analyzes strategies to enable the implementation of sustainable energy approaches in El Vizcaíno. Chapter five highlights several international examples that could be useful to inform organizational changes at the federal and state level aimed at fostering renewable energy and efficiency initiatives that enhance energy security, protect the environment, and also increase economic opportunities in El Vizcaíno and elsewhere in Mexico. Chapter six concludes the thesis by providing: a summary of all key findings, a broad analysis of the implications of the research, and an overview of future lines of inquiry.

This dissertation explores the potential of renewable energy and efficiency strategies to solve the energy challenges faced by the people living in the biosphere reserve of El Vizcaíno, which is located in the North Pacific region of the Mexican state of Baja California Sur. This research setting provides a practical analytical milieu to understand better the multiple problems faced by practitioners and agencies trying to implement sustainable energy solutions in Mexico. The thesis starts with a literature review (chapter two) that examines accumulated international experience regarding the development of renewable energy projects as a prelude to identifying the most salient implementation barriers impeding this type of initiatives. Two particularly salient findings from the literature review include the importance of considering gender issues in energy analysis and the value of using participatory research methods. These findings informed fieldwork design and the analytical framework of the dissertation. Chapter three surveys electricity generation as well as residential and commercial electricity use in nine coastal communities located in El Vizcaíno. Chapter three summarizes the fieldwork methodology used, which relies on a mix of qualitative and quantitative research methods that aim at enabling a gender-disaggregated analysis to describe more accurately local energy uses, needs, and barriers. Chapter four describes the current plans of the state government, which are focused in expanding one of the state’s diesel-powered electricity grids to El Vizcaíno. The Chapter also examines the potential for replacing diesel generators with a combination of renewable energy systems and efficiency measures in the coastal communities sampled. Chapter five analyzes strategies to enable the implementation of sustainable energy approaches in El Vizcaíno. Chapter five highlights several international examples that could be useful to inform organizational changes at the federal and state level aimed at fostering renewable energy and efficiency initiatives that enhance energy security, protect the environment, and also increase economic opportunities in El Vizcaíno and elsewhere in Mexico. Chapter six concludes the thesis by providing: a summary of all key findings, a broad analysis of the implications of the research, and an overview of future lines of inquiry.

Nearly all the 1.3 billion people in the world with no electricity access live in developing countries. On the one hand, electricity is a basic need. On the other hand, the environment should not be further damaged. Thus, sustainable electricity in developing countries is clearly needed. The aim of this dissertation is to analyse the mechanism of the diffusion and adoption of renewable electricity with particular focus on rural electrification among low-income inhabitants in developing countries. The dissertation is comprised of a cover essay and six appended papers with a mix of qualitative and quantitative methods based on several means of data collection. The first paper describes diffusion theory through a novel bibliometric tool. This novel method provides an overview, structure, and explanation of a large research area; complements a traditional literature review; and can be applied to any knowledge field. Here, the structure of the recent development of diffusion research, together with its application, are presented. With a specific focus on rural electrification among low-income inhabitants in developing countries, the diffusion framework is empirically applied with complementary concepts in the second, third, and fourth papers, based on three different cases. One case study investigates the adoption of electricity among rural inhabitants in Uganda and shows that a foreign company can be an important player in the rural electrification effort. Another case study addresses a large dissemination of photovoltaic systems provided by a local firm in Bangladesh and reveals that the diffusion of renewable energy can be effectively undertaken by a private local firm, rather than waiting for full government support or large multi-national corporations. The other case study discusses a small-scale diffusion of photovoltaic systems in a remote region in Thailand and presents an extreme case where full government support is necessary. In addition, through a systematic literature review, the barriers to adoption of photovoltaic systems are identified in the fifth paper, highlighting several remaining challenges. In the last paper, issues related to the transition to using photovoltaic systems in off-grid communities are discussed. The diffusion mechanism of renewable electricity has been shown to be a highly complicated process, having several unforeseeable and context-specific factors. A technology with superior qualities does not diffuse by itself but requires tremendous effort and close collaboration on the part of stakeholders. There are complex relations, on the one hand, between technology and society and, on the other hand, between technology providers and adopters. No single, fast, or straightforward remedy can address the complex nature of diffusion of renewable electricity in rural communities. Therefore, understanding the local context is highly important, indicating the need for empirical investigation. This dissertation offers several contributions concerning methodological, theoretical, empirical, managerial and policy. It also provides implications that may be relevant for actors who attempt to introduce, disseminate, and manage new energy technologies in rural communities. / Nästan alla av de 1,3 miljarder människor som inte har tillgång till el bor i utvecklingsländer. Å ena sidan är el ett grundläggande behov. Å andra sidan bör miljön inte skadas ytterligare. Det finns således ett behov av förnybar el i utvecklingsländer. Avhandlingens syfte är att analysera mekanismerna bakom diffusion och införande av förnybar el med särskilt fokus på elektrifiering av landsbygden bland låginkomsttagare i utvecklingsländer. Avhandlingen består av en kappa och sex bifogade artiklar som är baserade på en blandning av kvalitativa och kvantitativa metoder och innehåller flera olika typer av datainsamling. Den första artikeln beskriver diffusionsteori genom ett nytt bibliometriskt verktyg. Denna nya metod ger översikt, struktur, och förklaring till ett stort forskningsområde; den kompletterar en mer traditionell litteraturöversikt och kan tillämpas oavsett kunskapsområde. Här presenteras strukturen av den senaste utvecklingen inom diffusionsteori tillsammans med dess applikationsområden. Med ett särskilt fokus på landsbygdselektrifiering bland låginkomsttagare i utvecklingsländer tillämpas diffusionsramverket empiriskt med kompletterande koncept i den andra, tredje, och fjärde artikeln. Dessa artiklar är baserade på tre olika fallstudier. En fallstudie berör elektrifiering på landsbygden i Uganda och visar att utländska företag kan vara en viktig aktör i denna process. En annan fallstudie tar upp spridning av solcellssystem i stor skala som utförs av ett lokalt företag i Bangladesh och visar att spridning av förnybar energi effektivt kan genomföras av privata lokala företag, snarare än att vänta på statligt stöd eller stora multinationella företag. Den sista fallstudien diskuterar småskalig spridning av solcellssystem i en avlägsen region i Thailand och representerar ett extremfall som behöver full finansiering från staten. I den femte artikeln har hindren för införandet av solcellssystem identifierats genom en systematisk litteraturöversikt, artikeln belyser också många kvarstående utmaningar. Den sista artikeln diskuterar frågor som rör övergången till, samt användandet av solcellssystem i områden som inte är anslutna till elnätet. Diffusionsprocessen för förnybar el har visat sig vara mycket komplicerad med flera oförutsedda och kontextspecifika faktorer. Teknik med överlägsna egenskaper kan inte spridas av sig självt utan kräver stora ansträngningar och nära samarbete mellan de inblandade aktörerna. Det är komplexa relationer, å ena sidan mellan teknik och samhälle och å andra sidan mellan teknikleverantörer och användare. Det finns inte en perfekt, snabb eller enkel åtgärd för att ta itu med den komplexa karaktären av diffusion av förnybar el på landsbygden. Därför är förståelsen för den lokala kontexten av stor betydelse och detta understryker behovet av empiriska studier. Denna avhandling bidrar med kunskap som täcker områden som metodologi, teori, empiri, ledarskap och politik. Studien visar även på relevanta implikationer för de aktörer som försöker införa, sprida och hantera ny energiteknik till landsbygden. / <p>QC 20150518</p>

This study focuses on fabrication of dry adhesives mimicking gecko adhesion. We also look into the origin of the supreme adhesion of geckos, which have inspired the fabrication of fibrillar dry adhesives during the last decade or so. In principle, the superior material properties of ??-keratin (the main material comprising the fibrillar feature on gecko toe pads) along with the hierarchical high aspect-ratio fibrillar structure of geckos??? foot pad have enabled geckos to stick readily and rapidly to almost any surface in both dry and wet conditions. In this research, non-sticky fluoropolymer (Teflon AF) resembling ??-keratin rigidity and having an extremely low surface energy and dielectric constant was applied to fabricate a novel dry adhesive consisting of extremely high aspect-ratio nanopillars (200 nm in diameter) terminated with a fluffy top nanolayer. Both the nanopillars and the terminating layer were fabricated concurrently by replica-molding using a nanoporous anodic aluminum oxide membrane as the mold. In particular, upon infiltration of Teflon AF melt into the anodic aluminum oxide nanopores, the polymer melt fingered over the pore walls. The fingerlike structure formed during infiltration, subsequently collapsed after removal of the mold, developing a unique sheet-like nanostructure on top of the base nanopillars. Concurrent fabrication of the terminating nanostructure helps the fabrication of extremely high aspect-ratio (27.5???225) nanopillars which, up to an aspect-ratio of 185, neither collapse at the tip nor bundle. In order to fabricate nanopillars of different topographical properties, in our first approach, the height of the nanopillars as well as the size and density of the terminating nanostructure are carefully controlled by adjusting the processing temperature. Following that, a novel replica-molding technique for fabrication of bi-level Teflon AF nanopillars is reported. The developed technique relies on the concurrent heating and cooling of the Teflon AF melt which filled vertically-aligned alumina nanochannels. Unlike conventional polymer infiltration methods which consist of filling the mold by only heating the polymer above its glass transition temperature, in our novel method, the polymer melt is also simultaneously cooled down during the infiltration process. Concurrent cooling of the Teflon AF melt allows control over the interfacial instabilities of the polymer thin film, which forms ahead of the polymer melt upon its infiltration into the alumina nanochannels. Doing so, the geometrical properties of the subsequently developed peculiar fluffy nanostructure ??? after removal of the mold ??? on top of the extremely high aspect-ratio Teflon AF nanopillars (~25 ??m tall) are modified. In this project, we have also shown that the adhesion of the fabricated dry adhesives for the most part arises from electrostatic interactions of the applied polymer. In other words, Teflon AF, having an exceptional potential for developing electric charges at its surface upon contact with other materials via the so-called contact electrification phenomenon, can develop significant electrostatic interactions at its surface upon contact. In the current thesis, tribological results were discussed in detail to clarify the contribution of the structural properties of the fabricated dry adhesives toward their remarkable adhesion and friction forces generated via contact electrification. Nanopillars of specific geometrical properties have achieved remarkable adhesion and friction strengths, up to ~2.1 N/cm2 and 17 N/cm2, respectively (up to ~2.1 and 1.7 times larger than those of a gecko toe pad). It is commonly accepted that the adhesive performance of other synthetic bio-inspired dry adhesives is due to the formation of van der Waals interactions at the tip or side of the dry adhesives fibrils with the substrate they are brought into contact with. However, what has been usually neglected in this connection is that electrostatic interactions may also be developed at the contact between any two materials via the familiar contact electrification phenomenon. Although contact electrification is common and can have a large influence on interfacial interaction forces, its impact on adhesive properties of synthetic dry adhesives has been overlooked. Our results on adhesion of bi-level Teflon AF nanopillars, which can generate strong adhesion forces relying on electrostatic interactions arising from contact electrification, have brought to light again the idea that charging the surface of dry adhesives, specifically polymeric ones, can play a very crucial role in their adhesive behavior. From this perspective, the main reasons that have caused this lack of attention to this concept and the possible contributions of contact electrification to interfacial interactions of polymeric dry adhesives, other than bi-level Teflon AF nanopillars, are also thoroughly discussed in this thesis. Besides synthetic fibrillar dry adhesives, the possibility of the occurrence of contact electrification and its contribution to the supreme dry adhesion of geckos have also been overlooked for several decades. In this research, by the simultaneous measurement of electric charges and adhesion forces that gecko toe pads develop on two distinct substrates (a sticky and a non-sticky one), we have shown that the toe pads generate significantly large amounts of electric charge on both substrates. More importantly, we have found that there is a direct correlation between the contact electrification-driven electrostatic forces and the measured adhesion forces. Otherwise stated, we have shown that what makes the difference that geckos stick strongly to one surface and not to the other are the electrostatic interactions arising from contact electrification, and not van der Waals interactions, which have been considered as the prime source of adhesion of geckos for many years.

This dissertation consists of four self-contained studies concentrating on the productivity development following major technological breakthroughs. All four studies are concerned with measurement issues of productivity. Three of the papers use a comparative historical perspective and primarily focus on some of the differences and similarities in productivity growth following each technological breakthrough. A fourth paper solely focuses on the ICT revolution and the problems associated with measuring productivity in the Swedish Radio, television and communication equipment (RTC) industry. Paper 1, Technological Breakthroughs and Productivity Growth (with Magnus Henrekson), examines productivity growth following three major technological breakthroughs: the steam power revolution, electrification and the ICT revolution. The distinction between sectors producing and sectors using the new technology is emphasized. A major finding for all breakthroughs is that there is a long lag from the time of the original invention until a substantial increase in the rate of productivity growth can be observed. There is also strong evidence of rapid price decreases for steam engines, electricity, electric motors and ICT products. However, there is no persuasive direct evidence that the steam engine producing industry and electric machinery had particularly high productivity growth rates. For the ICT revolution, the highest productivity growth rates are found in ICT-producing industries. It is argued that one explanation might be that hedonic price indexes are not used for the steam engine and the electric motor. Still, it is likely that the rate of technological development has been much more rapid during the ICT revolution as compared to any of the previous breakthroughs. In paper 2, Do Hedonic Price Indexes Change History? The Case of Electrification, I investigate whether hedonic price indexing would also have large effects on measured price and productivity during electrification. The hedonic methodology is used on historical data for electric motors in Sweden in 1900–35. The results show that PPI-deflated prices for electric motors decreased by 4.8 percent per year based on hedonic price indexes. This indicates that prices decreased considerably more for electric motors compared to total manufacturing. Annual labor productivity growth in Swedish electric machinery in 1919–29 becomes 12.1 percent if the hedonic deflators are used. Thus, there is strong evidence that productivity growth in the electric motor producing industry was very high during the 1920s. In contrast to Sweden, US annual labor productivity growth was only, according to current best estimates, 4.1 percent in electric machinery compared to 5.3 percent in manufacturing in 1919–29. However, hedonic price indexes were not used to calculate US productivity. Finally, it is shown that the price decreases for electric motors in the 1920s were not on par with the price decreases for ICT-equipment in the 1990s, even if hedonic indexing is used in both cases. Paper 3, Parallel Development? Productivity Growth Following Electrification and the ICT revolution, compares labor productivity growth and the contribution to labor productivity growth in Swedish manufacturing during electrification and the ICT revolution. The paper distinguishes between technology-producing, intensive and less intensive technology-using industries during these two technological breakthroughs. The results show that labor productivity growth and the overall contribution to labor productivity growth were considerably higher in technology-producing industries during the ICT revolution compared to electrification. For example, the relative contribution to labor productivity growth in manufacturing from the technology-producing industry was 3.4 percent in 1920–30 compared to 34.4 percent in 1993–2003. On the other hand, the relative contribution to aggregate labor productivity growth was considerably higher in intensive technology-using manufacturing industries during electrification. These findings have an important policy implication, namely that it is much more important how productivity is measured for ICT products in the 1990s than for electric motors in the 1920s. Paper 4, The Swedish ICT Miracle: Myth or Reality?, investigates productivity development in Sweden in the 1990s. The results show that much of the recorded Swedish surge in labor productivity was due to the spectacular growth of the Radio, television and communication equipment (RTC) industry. However, the productivity growth of the RTC industry is very sensitive to value added price deflators. Unlike Sweden, the US uses hedonic price indexes for semiconductors and microprocessors which are important intermediate inputs in the RTC industry. Estimates based on the US intermediate input price deflators for semiconductors and microprocessors suggest that the productivity growth of the Swedish RTC industry during the 1990s can be questioned. This implies that the productivity growth of total manufacturing has also been overestimated. The results for Sweden are also interesting for other countries such as Finland, Ireland and South Korea, where ICT-producing industries have contributed substantially to labor productivity growth / Diss. Stockholm : Handelshögskolan, 2006 S. 1-21: introduction and summary, s. 23-194: 4 papers

This research investigates what rural villagers perceive as important and develops recommendations for improved electrification project implementation centring on user-perceived values (UPVs). UPVs capture more than the basic definition of value in the sense that they include benefits, concerns, feelings and underlying drivers that vary in importance and act as the main motivators in the lives of project beneficiaries as perceived at a given time. Low access to energy continues in rural sub-Saharan Africa despite significant investment by the development community. One fundamental reason is that energy infrastructure adoption remains low, as evidenced by the lack of project sustainability. To counter this, the challenge for energy project developers is to achieve sustainable long-term interventions through the creation of value for beneficiaries, rather than the traditional approach of focusing on short-term project outputs. The question of what is valuable to people in rural communities has historically not played into the design and diffusion of energy infrastructure development projects. This research drew on design and marketing approaches from the commercial sector to investigate the UPVs of rural Ugandans. To better understand the UPVs of rural villagers a new method, consisting of a UPV game and UPV framework, was developed. This method is suitable for capturing, understanding and mapping what rural populations perceive as important. Case study analyses were carried out in seven villages across rural Uganda. The case studies included the UPV game supplemented by non-energy-specific and energy-specific interviews with villagers. Additionally, interviews with experts were conducted to verify the UPV framework and to identify the gap between experts’ opinion and villagers’ perception of what is important. The research demonstrates the effectiveness of the UPV game in deducing the values of rural villagers. The findings demonstrate a disconnect in the ability to accurately capture and design projects which resonate with and respond to the UPVs of recipients of rural electrification projects. A comparison between the villagers’ statements and experts’ opinion regarding what is most valuable to rural communities reveals striking differences that point to a fundamental misunderstanding of rural community UPVs which are likely to be contributing to widespread electrification project failure.

Electrification (or now rare and obsolete electrization), carried out in Czechoslovakia primarily in the interwar years (1918-1939) has gone down in history as a symbol of the construction of a modern independent Czechoslovak state and its democratic society, encapsulating its overall, predominantly building, ethos. Electrification was based on the expertise, invention and high educational standards of the country's electrical engineering elite that approached this particular task as a fully formed group (especially in the period starting from the last third of the 19th century) and as a particularly excellently organized one in terms of its professional unions, specialist scientific knowledge and potential use of its expertise in industrial plants and production centres for electrification. Its key platform was the Czechoslovak Electrical Engineering Union (Elektrotechnický svaz československý, Czech acronym ESČ, 1919), an association closely cooperating with the state authorities, primarily the Ministry of Public Industry and its State Power Council, with an agency that represented the country's vital standardization base and which soon grew to be the powerful Czechoslovak Standardization Society (Československá normalizační společnost, known under the Czech acronym ČSN, 1920); the ESČ also...

The aim of this study is to investigate, analyse and evaluate the installed off-grid PV system in Mavuno girls’ secondary school that is located in a rural area in northwest Tanzania. The original motivation behind this study was the rapid degradation of the installed battery bank within less than 3 years. The PV system was installed before the actual operation of the school, so the study aimed to answer a very pressing question which is "What is the actual load profiles in the school?". There was a high need to identify the actual school load profiles to enable several concerned social actors to evaluate the system and to decide for future extensions. Therefore, the study aimed to analyse the implementation of electricity in the school by creating actual load profiles, analysing the system performance versus the users’ needs and evaluating the sustainability and utilization of implementation. The study followed a multi-disciplinary approach combining the social and technical aspects of PV systems implementation to seek further understanding of the users’ consumption behaviours. It thus included a 1-month of field work in June 2018 during which participant observations and semi-structured interviews together with load measurements were carried out so as to create load profiles that are considering the patterns and deviations in users’ behaviours. During the field work, 2/3 of the students were in holidays so the taken measurements corresponded to the school at 30 % capacity. That is why the study also included 4 days of inverter data logging after the 1-month field work by the technical head of the school to overcome the limitations in held measurements. The observations showed that the actual installed system was slightly different from the documentation. In addition, the local installation practices are not fully appropriate from the technical point of view, and are affected by local social norms, as will be discussed. Besides, the participant observations and held interviews with relevant social actors showed that the daily behaviours of energy users do not exactly follow the school daily routine. Consequently, the social study was important to create actual effective load profiles. The observations and responses from interviews together with measurements were used to categorize the school loads into 29 different units. Those units can be used for current load prioritizations and for future load extrapolations. The created load profiles also represent a useful addition to load databases used by energy researchers who work on similar rural electrification projects. After the field work, several characteristics were calculated by Microsoft Excel such as apparent power consumptions, active power consumptions, battery bank state of charge, load power factor and PV generated energy. The characteristics were used in calculations evaluating the energy balance in the system. The results of held calculations showed that lighting during dark hours accounted for on around 78 % of the logged daily apparent energy use, as it has a low a low average power factor of 0.28. It also showed that some loads if time-bounded, they will significantly decrease the daily energy consumption. The calculations were also used to run PVSyst simulations to evaluate the system sizing which resulted in the recommendation that either the array size should be doubled, or the apparent energy consumption should be decreased to half. The study included suggestions for possible improvements such as decreasing the reactive consumed energy by either replacing the currently used light bulbs with ones that have higher power factor ( ≥0.8 for example) or by installing a capacitive compensation for power factor correction. In addition, it was recommended to quantify the school loads according to their priority or importance and to regulate observed time-unbounded loads such as "pumping water" and "ironing". Lastly, the study discussed how generated electricity is utilized in the school and what opportunities for women empowerment have become potentially possible with the provision of electricity.

Le Cambodge est un pays situé en Asie du Sud-Est, avec grand potentiel de ressources en énergies renouvelables. Même fort de ce potentiel, la puissance électrique actuellement installée n'est pas suffisante pour tout le pays. Environ 80% de la population vit dans les zones rurales et 75% des ménages sont sans réseau électrique. Ils utilisent une batterie, le moteur diesel, des bougies ou du kérosène pour l'éclairage, la télévision, les multimédia et autres appareils ménagers. Une minorité des citoyens, dans la partie nord utilise des modules pico hydro électriques acheté dans les pays voisins pour éclairage. Mais la tension de sortie et la fréquence ne sont pas vraiment stables en cas de modification de la charge ou de la vitesse de rotation de la turbine. La durée de vie des appareils électroménagers peut ainsi être réduite et des réparations locales sont nécessaires. Des millions de Cambodgiens ne peuvent pas accéder à l'énergie électrique en raison de deux facteurs principaux : les barrières technologiques et les coûts d'investissement élevés. Nos activités de recherche visent à éliminer ces barrières technologiques en concevant des systèmes de production d'énergie pico-hydroélectrique avec une installation rapide et peu coûteuse, simple et adaptée à une application locale tout en gardant une qualité de l'alimentation électrique satisfaisante. La première partie de cet ouvrage décrit la situation de l'énergie dans les zones rurales du Cambodge où les gens sont confrontés à un manque d'alimentation électrique. En conséquence, ils ne peuvent ni améliorer leur niveau de vie, ni développer leur communauté. Les villageois riches utilisent une batterie de voiture, des systèmes photovoltaïques ou pico-hydroélectriques alors que les villageois pauvres utilisent des bougies ou du kérosène pour l'éclairage. Des entreprises locales fournissent des solutions électriques basées sur des énergies renouvelables, mais les prix sont inabordables et loin de leurs attentes. Par conséquent, une solution originale est proposée dans cette thèse avec la récupération de composants électriques d'occasion en vue de la mise en œuvre d'un nouveau système de génération d'électricité pour les zones rurales isolées. Il s'agit ici d'innovation frugale pour le bas de la pyramide sociale. Les composants utilisés sont : machine asynchrone, alimentation sans interruption (UPS), alimentation de PC et d'autres équipements électroniques, etc. Ces composants recyclés peuvent être rassemblés pour former ainsi une solution technologique intéressante permettant de délivrer la puissance de sortie nécessaire. La deuxième partie de ce mémoire présente la modélisation de l'étage de puissance de la machine asynchrone triphasée utilisée comme un générateur asynchrone monophasé avec une phase d'excitation et les deux autres phases connectées en série pour alimenter la charge. Cette configuration est nommée 'Excited Induction Generator (EIG)'. / Cambodia is a country located in Southeast Asia, with its high potential of renewable energy resource. Even if this country has a high potential for renewable, the installed power is still not high enough to cover the whole country. About 80% of population living in rural areas and 75% of the households live without electricity. They survive by using battery, diesel engine, candle, kerosene for lighting, TV, multimedia and some other household appliances. A few of residents in northern part of the country use pico-hydro power units bought from neighbor countries in order to electrify their houses. In these systems, the output voltage and frequency are not really stable while the load under load or speed variations. Consequently, the lifetime of household appliances could be reduced or the items damaged and local repairs are needed. Moreover, millions of Cambodian people cannot access neither take an advantage from the available energy resources due to two main factors: technology barriers and high investment cost. This research aims to remove technology barriers by designing simple systems for pico-hydro power generation with fast and simple installation, suitable for local applications with high quality of electrical supply. The first part of this work briefly describes the energy situation in rural areas of Cambodia where people are facing the lack of electrical supply which. They cannot neither improve their living standard nor develop their community. Rich villagers use car battery, solar PV applications, pico-hydro power while poor villagers use candle/kerosene for lighting. Local enterprises can provide renewable energy solutions but the prices are unaffordable and far from their expectations. Therefore, an original solution is proposed in this thesis by using wasted electric and electronic equipment (second-life components) to form the new power generation systems for remote rural areas. This is frugal innovation to serve the bottom of the social pyramid. The used components are: induction machine, Uninterrupted Power Supply (UPS), power supply of a computer and other electronic equipment, etc. These wasted components can be arranged together to form a good solution with an interesting output power. The second part of this thesis presents the modelling of the power stage of three-phase induction machine as a single-phase induction generator by using one phase for excitation while the other two phases are connected in series to supply load, named "Excited Induction Generator (EIG)". Capacitor banks are added to EIG for compensating the reactive power. Capacitor values influence poles and zeros locations which are described and analyzed in the root locus according to the parameter variations. The third part of this thesis is devoted to onsite modelling of losses in induction machine. The method should achieve results simply, rapidly, without any prior information on the machine, in order to further integrate this model into energy optimization algorithms. Design of experiments is a good candidate. Experimental models of the total loss (iron loss and rotor copper losses) are proposed for motor operation and generator mode for different machines of different powers. The last part of this thesis describes output voltage/current response for both simulation results and experimental results of the induction generators. Proportional-integral and proportional-resonant controllers are tested. The implementation of closed loop controller is first achieved in an analog circuit and then, with dSPACE/MATLAB Simulink environment.

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