Hydropower helps countries meet their energy needs in an economically, environmentally, and socially sustainable way while saving money and increasing energy security and self-reliance. Being one of the fastest developing countries, electricity demand of Turkey has been increasing and is expected to increase in the future. Untapped hydropower potential is among the prospective alternative resources to supply this demand. Developing a hydropower project requires a great deal of expertise in multiple disciplines. RETScreen software developed by CanmetENERGY helps the planners and decision makers to assess the feasibility of renewable energy projects at the pre-feasibility and feasibility stages. This study is an application of RETScreen to assess the feasibility of alternative formulations for Niksar HEPP, a small hydropower project which is under construction in Turkey. Three alternative formulations are generated and their economic performances are evaluated and compared. First, optimum design discharges are calculated and then economical analysis is conducted for various electricity export rates by RETScreen for all the alternatives. This study provides a detailed literature review on hydropower and its economical, social and environmental aspects, and shows how RETScreen can be used in assessing the economical feasibilities of the current formulation for Niksar HEPP and its alternative schemes.

In this study, alternative solution of Kayraktepe Dam is investigated. Kayraktepe Dam was planned more than 30 years ago, but due to various reasons the construction could not be realized. In this study, an alternative feasible formulation was developed. Former Kayraktepe Dam was planned for multiple objectives: flood control, energy generation and water supply for irrigation. The newly developed formulation was designed to meet these objects as well.

Es kann davon ausgegangen werden, dass sich die Erdbevölkerung bis Ende dieses Jahrhunderts verdoppeln wird. Der Energiebedarf wird sehr wahrscheinlich um mehr als das Doppelte steigen, da der Bevölkerungszuwachs ausschließlich in Entwicklungsländern stattfindet, wo bekanntlich ein erheblicher Bedarf an Energie besteht. Die Prognosen gehen daher von einer Zunahme der Energie aus, die unseren heutigen Verbrauch um das 2- bis 3- Fache übersteigt. Vor dem Hintergrund, dass die Energieoptionen – Rohöl, Erdgas, Uran – in diesem Jahrhundert nahezu aufgebraucht sein werden, gewinnen zunehmend die erneuerbaren Energien an Bedeutung. Die Wasserkraft ist dabei weltweit die bedeutendste regenerative Energiequelle. Die Planungen sehen vor, dass sich die Wasserkraftnutzung bis zum Jahr 2050 verdoppeln wird. / It can be expected that the world population will double by the end of this century. The energy demand will very probably increase even more significantly, as the population is increasing exclusively in the developing countries, where an extreme energy demand is already known to exist. Three to four times the present energy demand is predicted. When it is considered that crude oil, natural gas and uranium resources will be practically exhausted during the coming century, renewable energies become more and more important. Hydropower is worldwide the leading renewable energy source. It is planned to double the use of hydropower by the year 2050.

While most western hydropower sites are already developed or protected by legislation, the aging hydropower park requires refurbishment actions. Especially to tackle the challenges of an increased fluctuation at the grid coming from the expansion of other renewable energy sources such as wind power. The company Fortum is carrying out a number of major refurbishment projects every year and want to enhance their time performance during the outage. Delayed projects are resulting in unexpected costs and production losses. By investigating 20 historical refurbishment outages from a project manager perspective, the delays are related to different sections of the outage time. These sections are referred to as work packages, meaning a set of activities related to a functional part of the plant. The material is based on interviews and project documentation. The outages are divided into three groups depending on the amount of delay and some additional set of factors are used in a comparison. The results are discussed from a time management and a multi-project perspective. The study can be viewed as an initial study to address time management challenges in a company. The methodology proves to be an efficient way to get time management challenges at a company to the surface. The results displays late manufacturing deliveries and overruns of assembly and erection durations as the most common reasons of delay. A number of potential success/failure factors are suggested. It is also pointed out that small projects are at risk being more delayed compared to larger ones.

In Sweden, EU: s Water Framework Directive led to an investigation that started in April 2012 by the Swedish government, called Vattenverksamhetsutredningen freely translated to "Water Activities Survey", with the purpose to investigate the Environmental Code’s rules concerning water activities and water plants. The survey is divided into 3 reports, two sub-reports and a final report. One of the sub-report is focused on Swedish hydropower and the investigators found that many hydropower plants have old permits. One suggestion in the survey was to reconsider old permits so they would become consistence with today’s Environmental Code. There have been discussions regarding whether Sweden will lose much of its electricity production from hydropower as an outcome if the survey’s suggestions becomes reality. The aim with this literature study is to investigate how the EU: s Water Framework Directive and the Water Activities Survey will affect Swedish hydropower and if there will be a decrease in electricity production as an outcome if the suggestions made in the survey becomes reality. The results in this literature study shows that there will probably be a decrease in production for Swedish hydropower, but with how much is hard to say because the Swedish government has not yet decided what they will do with the suggested actions in the Water Activities Survey. A comparison is done with Sweden’s import and export statistics between the years 2001-2014 with a predicted loss of 13 TWh per year, which is a number taken from a survey made by Vattenfall. A comparison with a loss of half of 13 TWh per year is also done. Between the years 2001 and 2014 Sweden imported electricity 6 out of 14 years and exported electricity 8 out of 14 years. If adding the predicted loss of 13 TWh per year to the import and export statistics, Sweden would have had to import electricity 12 years and export 2 years. If adding a loss of 6.5 TWh per year Sweden would have had to import electricity 8 years and export 6 years. The conclusions is that Sweden will have to import a lot more electricity if only looking at import and export statistic if the loss of electricity is between 6.5-13 TWh per year.

With many states recently enacting either renewable energy mandates or goals,the small hydropower industry has a unique opportunity to supply a growing portion of U.S. electricity supply. But the procedure to obtain a license for project development is unwieldy, increasingly wrought with regulatory hurdles at both the state and Federal levels. Government incentives exist that promote the development of small hydropower,but are insufficient to overcome the regulatory barriers faced by the industry. Although it is possible for small hydropower to supply a growing share of energy production in the U.S., it is unlikely that the full potential will be realized without substantial changes to the renewable energy regulatory system. This study describes the current state of the regulatory system governing the development of small hydropower facilities in the United States. A basic overview of hydroelectric technology is discussed, followed by a detailed description of the process through which a project developer must apply for a Federal license to construct and operate a hydropower project. The current state of the U.S. small hydropower industry is examined, considering the potential opportunity for the industry to supply a growing share of the U.S. electricity supply. This analysis is supplemented by a discussion of the costs of project construction and an investigation into the regulatory barriers to project development. / text

Baihetan Dam is sited on the lower reaches of the Jinsha River in the southwest of China between the boarders of Sichuan and Yunnan province. The dam is scheduled to be taken into operation in the year of 2020 with an installed generation capacity of 14 GW which will put Baihetan Dam on the map as the third largest hydropower station in the world considering installed power output. In comparison, the world’s biggest dam Three Gorges has an installed generation capacity of 22,5 GW. To ensure a sufficient safety evaluation in terms of erosion (scour) formation at the bottom of the plunge pool, pressure simulations in the plunge pool floor in an experimental model at the Department of Hydraulic Engineering in Tsinghua University, Beijing, China has been performed. Data from two experiments with two different outflow configurations has been obtained and analyzed together with three earlier performed experiments on the same experimental model. The results from outflow configuration one had an incomplete data set and could not be compared to the other experiments. The results retrieved from the other experiments however showed the importance of a spillway design with nappe splitters and nappe blocks implemented and the value of a sufficient water cushion in the plunge pool. All four outflow configurations with nappe splitters or nappe blocks implemented held a hydrodynamic pressure below the recommended maximum pressure value of 15 cm water head (experimental model scale) stated by the East Asian Investigation and Design Institute, whilst the one configuration with no nappe splitters or nappe blocks exceeded the value. The design of outflow configuration two is four nappe splitters implemented in two spillways and two nappe blocks in two spillways. In this thesis, this configuration has proven to be the most suitable one in terms of maximum pressure minimization and pressure distribution at the plunge pool floor.

Ilgą laiko tarpą hidroenergetika vertinta kaip sėkminga žmonijos vystimosi ir akivaizdžios naudos išraiška, pastaruoju metu siejama su reikšmingu poveikiu gamtinei aplinkai bei įtaka klimato kaitai. Lygumų šalyse, net ir mažos galios hidroelektrinių statyba pareikalauja didelių užliejamų žemės plotų. Šiame darbe atlikome aštuoniasdešimties iki 2007 metų pastatytų hidroelektrinių poveikio aplinkai analizę bei aptarėme galimą „Lietuvos hidroenergetinių išteklių schemoje„ numatytų statyti HE poveikį aplinkai palyginant didžiąją ir mažąją hidroenergetiką. Atlikus tyrimą nustatyta, kad nedidelės galios hidroelektrinės poveikis aplinkai, lyginant pagaminamos energijos vienetui yra daug didesnis nei didelių hidroelektrinių atveju. Tam, kad pagaminti 1 kW elektros energijos – 100 kW galingumo hidroelektrinėje, reikės užlieti apie 0,5 ha žemės, kai tokiam pačiam kiekiui pagaminti didelėje (100MW) galios HE prireiks 0,06 ha užliejamos žemės. Planuojamų statyti hidroelektrinių atveju, nepriklausomai nuo regiono, hidroelektrinių tvenkiniai užlietų didelius, žemių plotus. Įgyvendinant „Lietuvos hidroenergetinių išteklių schemą“ būtų sunaikinti 670 km2. miškų ir žemės ūkio naudmenų. Vien tik užtvankos ant Nemuno užlietų 278 km2 užimantį plotą. Užliejamos žemės vertintinos kaip didelę ekologinę ir estetinę vertę turinčios teritorijos, pasižyminčiomis unikaliomis gamtinėmis buveinėmis ir turtinga rūšine įvairove. Užliejus teritorijas radikaliai pakeičiamas kraštovaizdis, prarandamos... [toliau žr. visą tekstą] / During the last century hydroenergy become one of the most important energy source in the world. However, the environmental impacts of dams have been disccused widely in recent years. Number of reserches indicates dams reservoir as an significant greenhouse gas source. The objective of this research was to evaluate the effects on environment made by electrical dams in country of flatlands. To assess all possible impact of designed power plants, analysis of more than 80 working electrical dams has been made. The impact of small and large power plants was considered. Analysis shows that there was a quite big difference in flooded land area per energy unit (kW), between low-power and high-power hydroelectric. Average flooded area for 100 kW power plant destroys over 0,5 hectare of species rich semi-natural grasslands forests and other landed property. When high-power (100MW) hydroelectric dam require only about 0,06 hectare of flooded land per unit. Thus, indicates that small water-plants gives much more negative impact per unit, than big ones. However, the impact of dams, are highly destructive in conditions of flatlands. Results has showed that further hydroenergy development in Lithuania, according to planned “Lithuanian hydroenergy resource use scheme” would require vast flooded area of total 670 km2. In addition, dams reservoir emit a significant amount of greenhouse gas to the atmosphere. The impact of Global warming will contribute 43960 thousand ton of CO2 and 580... [to full text]

Frequency control systems are used to keep the grid frequency at the nominal value of 50.00 Hz. Vattenfall employ hydropower plants for this purpose as they can easily adapt their production to counteract frequency deviations. This master thesis focuses on trying to improve Vattenfall’s mechanism to provide FCR-N (Frequency Containment Reserve in Normal operation) for primary frequency control, i.e. the turbine governor. The efforts are made to operate the plants more efficiently, decreasing distribution losses and thus increasing the profits. The current control system was modelled in MATLAB’s simulation tool Simulink to understand its complexity and to be used as base for comparison. Then a new model was developed based on the idea to introduce a global governor for the frequency control in each plant which controls the input signal to the individual turbine governors of each unit. OPT-data (tabulated data indicating how to operate a plant at the highest possible efficiency) was used to determine how to optimally distribute the FCR-N among the active units in a plant in real-time. The conclusions which can be drawn from this master thesis are that it is possible to make a more optimal distribution of FCR-N in real-time. However, it has not been possible to make a good comparison between the two models and the results regarding the profits which can be made by introducing this new type of governor are therefore inconclusive. It is of crucial importance to make a better match of the regulating strengths of the two models in order to perform the comparison. Improving the parameter values for the proportional and integral gains of the individual controllers and the precision of the OPT-table lookups may further improve the new model and also make it possible to perform a valid comparison between the two models.

abstract: Hydropower generation is one of the clean renewable energies which has received great attention in the power industry. Hydropower has been the leading source of renewable energy. It provides more than 86% of all electricity generated by renewable sources worldwide. Generally, the life span of a hydropower plant is considered as 30 to 50 years. Power plants over 30 years old usually conduct a feasibility study of rehabilitation on their entire facilities including infrastructure. By age 35, the forced outage rate increases by 10 percentage points compared to the previous year. Much longer outages occur in power plants older than 20 years. Consequently, the forced outage rate increases exponentially due to these longer outages. Although these long forced outages are not frequent, their impact is immense. If reasonable timing of rehabilitation is missed, an abrupt long-term outage could occur and additional unnecessary repairs and inefficiencies would follow. On the contrary, too early replacement might cause the waste of revenue. The hydropower plants of Korea Water Resources Corporation (hereafter K-water) are utilized for this study. Twenty-four K-water generators comprise the population for quantifying the reliability of each equipment. A facility in a hydropower plant is a repairable system because most failures can be fixed without replacing the entire facility. The fault data of each power plant are collected, within which only forced outage faults are considered as raw data for reliability analyses. The mean cumulative repair functions (MCF) of each facility are determined with the failure data tables, using Nelson's graph method. The power law model, a popular model for a repairable system, can also be obtained to represent representative equipment and system availability. The criterion-based analysis of HydroAmp is used to provide more accurate reliability of each power plant. Two case studies are presented to enhance the understanding of the availability of each power plant and represent economic evaluations for modernization. Also, equipment in a hydropower plant is categorized into two groups based on their reliability for determining modernization timing and their suitable replacement periods are obtained using simulation. / Dissertation/Thesis / M.S. Electrical Engineering 2011