As pequenas centrais hidrelétricas construídas na primeira metade do século XX, no município de Espírito Santo do Pinhal, são exemplos representativos do período inicial da eletrificação no Estado de São Paulo. Constituem-se de três usinas de pequeno e médio porte instaladas nas margens do Rio Mogi-Guaçu com grande potencial de patrimonialização em virtude dos valores histórico, arquitetônico, paisagístico, tecnológico de uma tipologia industrial pouco reconhecida no âmbito cultural. A pesquisa tem como objetivo propor um delineamento dos limites paisagísticos desse conjunto hidrelétrico, considerando os resultados de parâmetros ecológicos da paisagem como área, número de fragmentos de habitat, índice de fragmentação maior, distância do vizinho mais próximo, forma e área núcleo, analisados a partir do mapeamento de uso e cobertura da terra na escala 1:5.000. Também foram considerados aspectos de visibilidade da paisagem, calculados a partir de pontos determinados na barragem e na casa de máquinas das usinas, para verificar o alcance e direção do panorama a partir desses locais. A área de estudo foi delimitada com auxílio de cartas topográficas na escala 1:10.000 e ortofotos coloridas de 2010 considerando as características físicas e culturais da paisagem. Foram identificadas 17 classes de uso e cobertura da terra, recobrindo área total de 2.075,96 hectares. Apesar da predominância de classes de origem cultural, verificou-se que os remanescentes de vegetação nativa da Floresta Estacional Semidecidual (FES) ocupam 45,47% do total da paisagem. O limite proposto para proteção da paisagem hidrelétrica abrange as PCHs Salto de Pinhal, Pinhal e Eloy Chaves; significativos remanescentes da Floresta Estacional Semidecidual, diversos cursos d água e nascentes das subbacias do Rio Mogi-Guaçu, significativos fragmentos de vegetação nativa, totalizando 1.185,37 ha. / Small hydropower plants (SHP) built in the first half of the 20th century, in the municipality of Espírito Santo do Pinhal, are representative examples of the initial electrification process in São Paulo State. This complex of SHPs comprises three small and medium-scale plants installed on the margins of the Mogi-Guaçu River, with a high patrimonialization potential due to the historical, architectural, landscape and technological values of an industrial building type scarcely understood within the cultural scope. The research aims to propose a delineation of the limits of this hydroelectric set landscape, considering landscapes ecological parameters results, such as area, number of fragments of habitat, fragmentation index largest, average nearest neighbor, form index, and core area, analyzed from land use and cover maps at a scale of 1:5,000. Landscape visibility aspects, calculated from certain points located on the dam and the powerhouse, were also considered in order to verify the extent and direction of the panoramic view of these sites. The study area was delimited using 1:10,000 scale topographic maps and colored orthophotos of 2010, considering physical and cultural aspects of the landscape. Seventeen (17) classes of land use and cover have been identified, with a total area of 2,075.96 ha. Despite the predominance of cultural classes, it was found that the remaining native vegetation of the Semideciduous Seasonal Forest (SSF) covers 45.47% of the current landscape. The limits proposed for the hydropower landscape protection encompasses the Salto de Pinhal, Pinhal and Eloy Chaves Small Hydropower Plants, as well significant remaining native vegetation of the Semideciduous Seasonal Forest, several water bodies and sources of Mogi-Guaçu River sub-basin, and significant native vegetation fragments, totaling 1,185,37 ha.

<p>Denna rapport sammanställer vattenhydraulikens möjligheter samt fördelar och nackdelar vid konvertering av befintliga hydraulsystem, eller nya anpassade system inom vattenkraften. Dessutom ska en jämförelse mellan miljöpåverkan av olja jämfört med vatten som behandlats för att passa i olika hydraulsystem redovisas. En stor fråga är om vattenhydrauliken har samma hållbarhet som oljehydrauliken och ifall man får accelererad nötning ifall man konverterar ett befintligt system från oljehydraulik till vattenhydraulik.</p><p>Vattenhydraulik i vattenkraft används redan till luckservon. För ledkransservo ställs högre krav på driftsäkerhet men vatten bör kunna användas där med. Pitchkontroll för kaplannav är under utveckling, det som saknas just nu är sviveln som sitter längst upp på turbinaxeln. Om man ska konvertera ett nav behöver man också byta ventilerna som sitter i navet för att få tillförlitlighet.</p><p>För att kunna konvertera ett oljehydrauliksystem till vattenhydraulik behöver man byta vissa komponenter: ventiler, filter och pumpar då dessa behöver vara anpassade för att kunna få en anständig livslängd. Livslängden är garanterad till 8000-10000h för ett nyinstallerat vattenhydrauliksystem, detta är med avseende på pumpen som normalt sett är den detalj med kortast livslängd i systemet. Jämfört med oljehydraulik så är detta i stort sett samma livslängd, vilket har varit målet för leverantören Danfoss utveckling av vattenhydraulik.</p><p>Ett vattenhydrauliksystem med rent vatten som hydraulmedium påverkar miljön minimalt om ett läckage sker, ett system med monopropylenglykol i vattnet ger väldigt liten påverkan då detta oftast är nedbrutet efter 24h i naturen enligt Dowcal som producerar glykolen. Monopropylenglykol är dessutom giftfri samt har inga påvisade fall av allergi, vilket gör arbetsmiljön och hanteringskostnader betydligt lägre än för hydraulolja. Olja behöver förhöjd temperatur i jord för en acceptabel nedbrytning, och även då tar det förhållandevis lång tid.</p><p>Livslängden på glidbussningar förekommande i Älvkarleby luckcylindrar har utretts genom en laboration där friktion och nötning studerats med hydraulolja respektive monopropylenglykol med vatten (50/50). Kontakten var glidande rulle mot plan. Dessa tester visar att nötningen är desamma för kompositmaterial mot kromat stål, som testats i de båda medierna. Friktionsvärdet var lägre när man hade monopropylenglykol med vatten som smörjmedel.</p><p>I fallet med brons mot kromat stål var resultatet detsamma, monopropylenglykol med vatten gav lägre friktionsvärde och återigen gavs samma slitage vid jämförelse av provbitarna som gått i hydraulolja respektive monopropylenglykol med vatten.</p><p>Slutsatsen är att vattenhydraulik är ett bra alternativ till oljehydraulik, men ingående kunskap om hydraulikens systemkomponenter vid vätskekonvertering är nödvändig. Till exempel om materialen i systemet lämpar sig för konvertering eller behöver bytas ut.</p> / <p>This report puts together the possibilities of water hydraulics. It also compare pros and cons of new adapted systems or when converting existing oil hydraulic systems to water hydraulics. A small comparison of environmental effects from oil and water treated for use in hydraulic systems will be made.</p><p>A large question concerning water hydraulics is if it has the same durability as oil hydraulics. Another is if you get accelerated wear when you convert an oil hydraulic system to water hydraulics. For hydropower, Water hydraulics is already used for sluice gates. For the operating ring you need very high reliability but water hydraulics should be suiting for this application as well. Pitchcontrol for kaplanrunners is under development, at the moment the swivel on top of the turbineshaft is missing. If you want to convert a kaplanrunner you will also need to change the valves in the hub to get a good reliability.</p><p>To be able to convert an oil hydraulic system you need to change some components: valves, filters and pumps, these needs to be adapted for water to have a reasonable lifetime. The lifetime is guaranteed to be 8000-10000h for a recently installed water hydraulics system. This is regarding to the pump, which is the part of both water- and oil- hydraulics with the shortest lifetime. If you compare water- with oil- hydraulics they have about the same lifetime. That has always been the goal for the supplier Danfoss development of water hydraulics.</p><p>A water hydraulic system with pure tap water as pressure media will not affect the environment at all. Systems with monopropylen glycol and water as media will have only a small environmental influence. Monopropylen glycol that has leaked out will be broken down in 24h if it is taken care of in a cleaning plant. In the nature it will take slightly longer according to dowcal who produces the glycol. Monopropylen glycol has no cases of allergy reported, which makes the working environment and handling better than for hydraulic oil. Oil needs elevated temperature and the presence of earth to be able to break down, and still it takes considerable time.</p><p>The lifetime on sliding bushings existing in the hydraulic cylinders for Älvkarleby hydropowerstation sluice gates have been investigated by laboratory work. Friction and wear was compared with hydraulic oil or monopropylen glycol with water (50/50). The contact was a sliding wheel against a sheet. These tests shows that the wear is equal if you test a composite against chromed steel, with the two different hydraulic medias. The friction was however lower when you tested it with monopropylen glycol and water as lubricant.</p><p>In the case bronze against steel the results were the same. Monopropylen glycol with water gave lower friction, though the wear was equal between the two medias.</p><p>The conclusion is that water hydraulics is a good alternative to oil hydraulics, thorough knowledge of the hydraulic components is necessary though. For instance if the materials in the system is suitable for use in water hydraulics, or needs to be changed.</p>

In assuring the energy supply of Turkey, hydroelectric energy plays one of the most important roles in plans formulated to realize equilibrium between energy production and consumption. Hydroelectric power plants on Murat River, a tributary of Euphrates, is a part of the development plan for energy production. Operation of four dams in cascade on Murat River are simulated by using program package HECResSim. For this purpose, ten scenarios are formulated to utilize the hydraulic potential of Murat River between the elevations of 870 m 1225 m. This study provides detailed financial analyses of scenarios and shows how HEC-ResSim program can be used in formulation of alternative scenarios. Electric energy storage requirement due to the rising demand for peaking power is creating a completely new market value, which is also increasing the attractiveness of pumped storage power plants. The results of the simulation performed in Scenario 10 in which two pumped storage power plants are considered have 15% higher internal rate of return value than the other scenarios with conventional turbines. Results demonstrate the increasing attractiveness of the cascade system with reversible pump turbines.

This paper argues for the importance of scale, management and sovereign-led development in considering a more human-centric model for Third World development. It begins by reviewing the history of the mainstream Western development model through the evolution of modernization theory and foreign aid. It explores general critiques of this model offered by scholars, focusing on unequal power relations, the high cost of aid, and problems with ‘cookie cutter’ style development projects that don’t take into account disparate environments. As the paper progresses, focus shifts more specifically to hydropower development and ‘Big Dams’. Nepal is the main case study for exemplifying the problems with foreign-aid-funded dam projects and for proposing the alternative model of smaller scale, management-focused, nation-led development projects. While the scope of this study is limited, the growing success of these projects in Nepal suggests that more focus should be paid to applying these methods in other developing countries.

The research focus of this thesis is on modelling techniques for river kinetic turbines, to develop predictive numerical tools to further the design of this emerging hydro technology. The performance benefits of enclosing the turbine in a shroud are quantified numerically and an optimized shroud design is developed. The optimum performing model is then used to study river kinetic turbines, including different anchoring systems to enhance performance. Two different turbine numerical models are studied to simulate the rotor. Four different computational fluid dynamics (CFD) turbulence models are compared against a series of particle image velocimetry (PIV) experiments involving highly-separated diffuser-flow and nozzle-flow conditions. The risk of cavitation is briefly discussed as well as riverbed boundary layer losses. This study is part of an effort to develop this emerging technology for distributed power generation in provinces like Manitoba that have a river system well adapted for this technology. / May 2007

Mega projects are in most cases considered as the necessary evil of development. Before their benefits can be reaped, a lot of sacrifices and tough choices have to be made. The fear and uncertainties surrounding such projects range from the impacts on the local people, on the environment, the costs of investment, and to, if the project will deliver the promised benefits. Because of these fears and uncertainties, it is not unusual that most if not all such projects meet a lot of critics and resistance before their success or failures are witnessed. Today, it is more of a requirement than a belief (although without a guarantee) that stakeholders’ involvement and their active participation in all decision-making process concerning a project is the surest way of minimizing conflicts and ensuring justice. The Bujagali hydropower project being an example of such projects and without immunity to the problems faced by other mega project around the world has been a case study for this thesis. This study has therefore focused on institutional arrangements that governed the management and utilization of water resources in connection to hydropower development along the Nile River in Uganda, the procedures and stages of the negotiations for hydropower infrastructure development in Uganda, identified the major stakeholders that take part in such negotiations and looked in detail for what their issues and interests are. It has also examined the attitudes and opinions of stakeholders on the potential and benefits of hydropower against (solar, bio-fuel and geothermal) energy sources in the context of Uganda, taking into consideration the need for socio-economic development, preservation of culture and environmental protection. Finally, it has analyzed the conflicts/controversies that have arisen in the Bujagali hydropower project.

The accuracy, ease of use, and execution time of the finite element method based software Maxwell coupled to the system simulation software Simplorer was evaluated for simulation of hydropower generator - power grid interaction. A generator test rig were modelled in Maxwell and coupled to Simplorer with a strong circuit coupling as a single machine infinite bus system. The accuracy of the model was measured by comparing the simulated output power oscillation frequency and damping characteristics to the measured ones after a torque step. The result shows that the difference in output power oscillation frequency between the model and the generator test rig was small, and that the difference in damping characteristics was significant. The usability of the software package was found to be fair, as were the execution times.

The total amount of frequency deviations have during the last decade increased exponentially in the Nordic synchronous power system. The transmission system operators have therefore decided to implement load frequency control as a new automatic control system to stem these frequency deviations. The aim of this feasibility study is to analyse the effects of an LFC implementation in Swedish hydropower stations by using a more dynamic river governing. The method chosen to analyse the effects of LFC-governing was to create a Matlab Simulink hydropower station library including dynamic modules for rivers and turbine governors. The library is then used to create a river reach that is implemented in an ENTSO-E model for the Nordic frequency reserves. The governing of the river uses economical dispatch theory to optimally distribute a LFC setpoint signal from the ENTSO-E model to the different hydropower stations. Results show that the developed method has a future potential to create more frequency controlled reserves. By creating a central governing unit it was possible to govern frequency controlled reserves over an entire river reach under certain scenarios, but there are still many obstacles to overcome before an actual implementation. The method does however show both the possibilities and drawback of frequency controlled reserves in cascade coupled hydropower systems.

Background: China is the country with the worldwide hugest hydropower reserves. Interms of meeting its electricity demand, further development of its reserves is necessary.European companies are leading on the hydropower market and strive for projects inChina, resulting in challenges and opportunities while facing emerging market features.Aim: This study presents an analysis of the Chinese electricity market with the aim toidentify challenges and opportunities European hydropower companies face whenoperating or entering this market. The analysis uses Blue Ocean as strategic tool to finda new perspective of examining the market situation and potential.Definition: The OECD (2007) defined hydropower as “electricity generation using thepower of falling water”.Method: This study is based on qualitative research. It constitutes five expertinterviews with company employees as Voith and a professor for fluid mechanics andhydraulic machinery at Stuttgart University.Results: The analysis resulted in 12 challenges and opportunities for Europeanhydropower companies. The challenges arise mainly from political influence on theChinese market. Opportunities, on the other hand, have strategic implications on alltime horizons but focus on different technologies and directions. The long term strategicopportunity was identifies by applying the Blue Ocean strategy. Further this proves theex ante applicability of the Blue Ocean strategy.

The number of integrated wind farms into the power system is increasing as well as the total installed wind power capacity, which may cause voltage stability concerns. Additionally, there are European Transmission System Operators (TSOs) that do notinvolve wind farms in contributing to the voltage control in any significant extent. In the on-going project by the European Network of Transmission System Operators for Electricity (ENTSO-E), to update the European grid requirements, this will probably be changed. The aim of this Master thesis is to demonstrate the voltage variations in the high voltage grid during different operational conditions. Thereafter, clarify when high voltages may occur at the connection point of the studied wind farm. Furthermore, it is investigated whether the wind farm is able to regulate the voltage in the cases when high voltages occur. The load flow and switching studies are performed with the software tool Power System Simulator for Engineering (PSS/E) version 32.1.1. The grid model represents a part of the Swedish high voltage grid. Since voltage stability often is a local issue, special modelling aspects has been performed at the hydropower generators in the close-located area of the wind farm. The main conclusions of this Master thesis are that high voltages is associated with low load situations, i.e., mostly during summer nights. Furthermore, the studied close-located reactor is not able to keep the voltage within desired level by itself. Finally, it has been shown that the wind farm is technically able to contribute to the voltage stability in the close-located area. But since wind power is an intermittent power source it makes the voltage regulating capacity less reliable compared to hydropower. The results and conclusions given in this Master thesis have also been summarized in a conference paper for The 11th International Workshop on Large-Scale Integration of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Power Plants, see Lidström et al [35].