This project work focuses on the feasibility study of a hybrid PV-Wind System for rural electrification at the Estatuene Locality in southern Mozambique. This is in line with electricity network expansion, which, in Mozambique shows high implementation cost and low operation cost. Through field research, an analysis was made of the actual electrical demand in the Estatuene rural community. The wind data was collected from the installed weather stations in the region while the solar data were extracted internally from the HOMER software by introducing the site coordinates. All the configurations, simulations and selection of hybrid systems were also made using HOMER. For the Estatuene rural community it was estimated a scaled annual average demand of 9.4 kWh/day with a peak load of 1.4 kW for DC charge; and a total scaled annual average of 133 kWh/day with a peak load of 15.3 kW for AC Charge. The annual mean solar potential is 5.205 kWh/m2/d, and the mean wind speed is 4.84 m/s for 12 meters above the ground. Thus the calculations and the selection of the best configuration of the hybrid system were crossed out with the technical specifications and costs of photovoltaic panels, wind turbines, power converter, batteries, and the electricity network, specifically for the comparison between an optimum hybrid system solution and two separate ones. The calculations presented an analysis of the technical and the financial viability of the selected hybrid system for local electric power production.

Wind power is a fast-growing industry (GWEC, 2013) and already accounts for seven percent of the total electricity consumption in the EU. The largest market in the EU, and the third largest in the world, is Germany, with an installed base of 31 GW onshore. This master‟s thesis has examined the German onshore wind power market from a developer perspective, through a market study based on existing literature and semi-structured interviews with industry experts, a case study of a developer competing in the market and a survey, with the aim of investigating the sourcing models used as well as the success factors and challenges the developers are facing.  The study has found that Germany is a large, growing market with a generous feed-in tariff based support scheme, offering low-risk investments in wind power. However, there are many challenges for wind power developers, such as limited availability of designated areas for wind power development, non-uniform regulations, fierce competition and acceptance issues.  The authors believe that the future growth of the German onshore market will come from repowering and that having local contacts and credibility offer distinct advantages in the highly competitive arena.

In recent years, large investments have been made in wind power, and this trend is expected to continue in the coming decades. Integrating more wind power in the production mix offers great opportunities for the society, such as reducing greenhouse gas emissions and the dependence on foreign fuel. Large wind power penetration does, however, require changes in the way power systems are planned and operated. The power transfers across the electrical grid are determined by the load and the production. A secure operation of power systems requires that these power transfers stay within certain limits. Frequency control schemes are crucial for ensuring the balance between the electric demand and the production. They enable system operators to re-dispatch the production (for example via the activation of balancing bids) during real-time operations to follow the load variations. With wind power, these frequency control schemes must not only meet the variations of the load but also those of the wind. An optimal use of the frequency control reserves would allow system operators to operate the system in the most cost effective and secure manner, that is, using the cheapest available resources while taking into account the stability limits of the system and the uncertainty. With no wind power, the load is the main source of uncertainty, and it can be forecasted accurately. This enables system operators to dispatch the generation in the most cost-effective way to meet the load while keeping the system within its stability limits. Adding wind power to power systems, on the other hand, introduces a new source of uncertainty on the production side, which is more difficult to forecast. The tools used today for computing the stability limits and operating the system do not consider the whole range of possible future load and wind power production levels, but only pick a few likely values in this range. In this work, we propose a new approach which accounts for the whole uncertainty in the load and wind power, and gives the optimal re-dispatch which ensures a given level of system security given this uncertainty. The approach is a so-called Stochastic Optimal Power Flow (S-OPF) formulation, developed in the scope of this project for the optimal activation of balancing bids. It is a nonlinear optimization problem with one probabilitistic constraint ensuring a certain level of system security -- computed as the probability that the system stays within its stability limits -- and whose objective function is the minimization of the generation re-dispatch. Compared to what is done today, the S-OPF formulation enables system operators to consider the uncertainty when making decisions. An approximation of the proposed S-OPF formulation is developed to render the problem tractable. In particular, the stability boundary, defined as the set of stability limits, is approximated by second-order approximations. The accuracy of these second-order approximations are analyzed in the IEEE 9 bus system by computing the distance between the actual boundary and its approximation. The S-OPF problem is then solved in the IEEE 39 bus system using the approximated stability boundaries. Monte Carlo simulations are run in order to assess the accuracy of the approximation and check whether the optimal solution of the approximation does ensure the specified level of system security. / <p>QC 20121121</p>

Bei der Errichtung von Windenergieanlagen in Mittelgebirgsregionen ist darauf zu achten, daß an windexponierten Standorten die Gefahr einer Vereisung der Rotorblätter besteht. Es wurden klimatologische Daten im Bereich der Mittelgebirge ausgewertet und daraus eine Karte erarbeitet, in der die jährliche mittlere Häufigkeit der Tage mit Eisablagerungen dargestellt ist. / With the installation of wind turbines in low mountain areas the hazard of ice accretions on rotor blades at windy places must be considered. Interpreting climatological datas of the low mountain areas of S. E. Germany a map has been produced which shows the annual frequencies of days ice accretions on structures occurs.

The global emission of greenhouse gases is perceived as one of the most prominent threats to the world today and a socio-technological transformation (STT) of the energy industry is considered essential for long term sustainability. Organisations’ decisions to participate in the diffusion of electricity generation from renewable energy sources (RES-E) are deemed essential for achieving the transformation. Governments have therefore introduced support systems promoting RES-E, and since 2003 a radable green certificate (TGC) system has been used to support increased diffusion. However, there are a number of uncertainties regarding investments in onshore wind power which may, or may not demotivate investors to take further part in the diffusion of the technology. Understanding the magnitude and impact of uncertainties is of interest as they can act as barriers for achieving STT. This thesis contributes to the understanding of uncertainties in the Swedish-Norwegian TGC system by exploring two groups of uncertainties; technology uncertainty and volume uncertainty. Evaluation of the technology and volume uncertainty in the Swedish-Norwegian TGC system has been performed by statistically investigating the relationship between technological development of onshore wind power and the certificate price, as well as the accumulated surplus of certificates and the certificate price. The surplus of certificates accumulated on the Swedish-Norwegian TGC market has also been tracked to its source of origin. In addition, the financial results of previous onshore wind power investments have been estimated. The results have been validated by interviews with Swedish wind power investors. The results indicate that both the technology development of onshore wind power in Sweden and the accumulated surplus on the market have impacted the price of certificates, and thus also the profitability of investors in the system. The technology development of onshore wind power has been difficult to forecast, resulting in a considerable technology uncertainty perceived by investors. Regarding volume uncertainty, of the total accumulated surplus of certificates at the end of 2014, 70 % can be derived from forecast errors of quota obliged electricity production by the Swedish Energy Agency. In addition, there is a possible relationship between lower costs of onshore wind power and the accumulated surplus of certificates on the Swedish-Norwegian TGC market. The major implication of these uncertainties is that previous investors choose to delay or refrain from further onshore wind power investments. If actors choose not to participate in further diffusion of the technology, this could potentially harm the STT of the energy industry in Sweden. Introduction of long term contracts, more frequent quota adjustments and a record of RES-E investment decisions could potentially reduce the uncertainties perceived by investors. / De globala utsläppen av växthusgaser anses av många vara samtidens stora utmaning och en socioteknisk omställning av energisektorn framhålls som en nödvändighet för en hållbar framtidsutveckling. Elproducenters deltagande i utbyggnad och utveckling av förnyelsebar elproduktion förespråkas som en viktig del av denna omställning. I led med den politiska agendan har flertalet stödsystem utvecklats vars mål är att stödja utbyggnaden av förnyelsebar elproduktion. I Sverige introducerades 2003 ett stödsystem med gröna elcertifikat vars mål är att främja utbyggnaden av förnyelsebar elproduktion i landet. Stödsystemet till trots är investeringar i landbaserad vindkraft i Sverige fortfarande  associerat med stor osäkerhet i form av teknologins och marknadens framtida utveckling. Dessa osäkerheter kan hämma fortsatt utbredning av förnyelsebar elproduktion vilket kan leda till fördröjning eller stagnation av den nödvändiga omställningen mot en hållbar energisektor. Denna examensuppsats bidrar med kunskap kring de osäkerheter som råder inom det svensk-norska certifikatsystemet genom att undersöka två huvudsakliga osäkerheter; teknikutveckling samt överskott av certifikat på marknaden. Osäkerheten kring teknologins utveckling har undersökts genom att statistiskt utforska ett möjligt samband mellan teknologins kostnadsutveckling och marknadspriset av elcertifikat. Volymosäkerheten på marknaden har undersökts på ett liknande sätt där ett möjligt samband mellan överskottet av elcertifikat och marknadspriset av elcertifikat har utforskats statistiskt. Vilka faktorer som bidrar till överskottet av elcertifikat på markanden och från vilka källor dagens ackumulerade överskott härstammar har identifierats. Vidare har lönsamheten för tidigare investeringar i landbaserad vindkraft i Sverige uppskattats och analyserats. Resultaten antyder att såväl teknikutveckling som överskott av elcertifikat har haft en  etydande påverkan på marknadspriset av elcertifikat. Detta har i sin tur påverkat lönsamheten för investerare i systemet. Teknikutvecklingen har varit svår att förutse vilket resulterat i att investerare upplever stor osäkerhet kring framtida lönsamhet. Vidare visar resultaten att 70 % av det totala överskottet av elcertifikat på marknaden vid slutet av 2014 har sitt ursprung i Energimyndighetens felaktiga prognoser av kvotpliktig elanvändning. Det är även troligt att det finns ett samband mellan teknikutvecklingen och det överskott av elcertifikat på som genererats på marknaden. Innebörden av de två analyserade osäkerheterna är att investerare potentiellt fördröjer eller helt avstår från fortsatta  investeringar. Detta är problematiskt då det kan hämma utbredningen av förnyelsebar  lproduktion och verka som ett hinder för omställningen mot en mer hållbar energisektor i Sverige. Genom att introducera långtidskontrakt för handel med elcertifikat, mer frekventa kvotjusteringar samt etablera ett register över investeringsbeslut kan den osäkerhet som investerare i systemet upplever idag minskas.

Community energy is an umbrella term encompassing various forms of renewable energy initiatives involving citizens and communities. These initiatives have been highlighted as a strategy for more sustainable and just energy systems. While community energy is a marginal phenomenon in Sweden, there are still around 140 active community energy initiatives of which the majority are wind power cooperatives. An overview of both active and discontinued wind power cooperatives gives evidence of different types and levels of collaborations with municipal energy companies, pointing to the vital role these play in the emergence and development of wind power cooperatives in Sweden. Still, there is a lack of research engaging with wind power cooperatives on the local level. With this thesis, I address this research gap by conducting a qualitative case study of four wind power cooperatives in Sweden exhibiting different types and levels of collaborations with municipal energy companies. The aim is to explore ways to conceptualise these collaboration structures and create a better understanding of the implications they have on the emergence and development of energy cooperatives in general. To this end, I use the concept of modes of governance as an analytical tool to discern, describe, and conceptualise the various ways in which wind energy cooperatives and municipal energy companies collaborate. The findings indicate both differences and similarities between the various cases in terms of how and why wind power cooperatives and municipal energy companies collaborate. The results suggest that a productive and supportive collaboration structure between energy cooperatives and energy companies is characterised by principles of co-production such as mutual interests and benefits. In turn, the conditions for such a collaboration depend on internal and external factors such as personal ties, individual engagement, and institutional aspects like policies and tax rules. Further, the study indicates that while cooperative ownership still has a role to play in the expansion of renewable energy in Sweden, it will likely remain a niche phenomenon whose emergence and survival is dependent on facilitation and guidance by governments.

The necessity of increasing the generation of renewable energy is extensively recognized, however its expansion requires social and political acceptance. Wind power is seen as a promising and vital source of energy, and with new technology, it is expected to grow significantly. However, empirical experience indicates that the number of decisions to apporve wind power applications has declined, and resistance is expected to be the cause. The aim of this research study is to analyze and evaluate to what extent economic compensation or economic incentives could influence social acceptance of wind power in Sweden through the lens of the theoretical framework of energy justice. The study uses a mixed method approach while examining the principles of distributional and procedural justice. The quantitative method using surveys and a qualitative method using semi-structured interviews provided the base for the outcomes. The results demonstrate that communities often resist wind power projects, and compensation is likley to influence acceptance of wind power and is thus seen as vastly important and a requirement for future development. The injustice of current compensation systems and low involvement in the decision-making process among local residents are further considered issues for the development of wind power. This further indicates attention to energy justice using distributional and procedural justice as a framework to integarte wind power into a social context to avoid unfairness between the burden and benefits of those affected by wind power.

Offshore wind is rapidly growing and optimised grid connections are crucial for its success. Generally, costs and losses are higher for HVDC at short distances due to the converters, while HVAC costs and losses increase more rapidly with distance due to the ac cables. Hence, there is a breaking point over which HVDC becomes beneficial, which is important knowledge for grid connection design. Recent research and practice indicate increasing distances for the breaking point, enabled by the introduction of offshore reactive compensation substations (RCS) for HVAC. In the study, steady-state models of HVAC and modular-multilevel converter (MMC) based VSC HVDC systems up to 260 km have been simulated in the Matlab/Simulink based program EeFarm-II. For base case assumptions, the average loss breaking point is 80 km and the levelised cost breaking point is 229 km. The resulting breaking point with respect to levelised cost of energy (LCOE) is 205 km and with respect to net present value (NPV) 186 km, agreeing with the trend of increasing breaking points. Given the range of distances in literature, it is of interest to also investigate how the breaking point depends on assumptions on technical, practical and economic parameters. For the NPV breaking point: lifetime and interest rate have no impact, availability and cost of RCSs have low impact, electricity price has moderate impact, operation and maintenance (O&amp;M) cost has high impact while investment cost and lead time have very high impact. This could be taken into consideration in offshore projects and in future research.

Combating climate change has become the key objective of the 21st century. Energy transition, with the intensive introduction of the renewable energy sources to the world’s energy systems, is one of the biggest driving forces in stimulating global sustainable development. Growing shares of renewables, including wind power as a major player (35% of the world’s electricity needs by 2050 raised the issues of grid stability and supply/demand balancing (IRENA, 2019). A popular view on solutions for these issues lies with global energy interconnections, which could support grid stability and let the countries trade green electricity between themselves, creating big regional or even global electricity markets. These interconnections would call for close cooperation between the states, not only in the sphere of transmission, but in generation as well. The cross-border character of such projects would bring new aspects and nuances to the wind power developer’s work, making it more complex and politically sensitive. The potential planning process of such wind power projects has not been investigated before. Therefore, in order to fill this research gap, a cross-border wind power environment analysis framework was developed on the basis of the reviewed literature to assist a wind power developer in a potential planning process of a complex cross-border wind energy project in a sensitive setting. The developed framework was then used to evaluate an empirical case of an assumed offshore wind park on the Southern Kuril Islands, a disputed territory between Japan and Russia. The results showed that introduction of the cross-border factor makes permitting and coordination of projects more challenging and confusing. In addition to that, the wind power developer might have to contribute to the development of improved wind power regulations and norms. Moreover, coordination of such projects would not involve only the developer, but most likely representatives of the involved countries and regions, and possibly mediating organisations; the developers’ work would take place in a multicultural environment with people of various traditions, values, economic backgrounds and interests, which would complicate balancing the stakeholders’ interests during the planning phase.

The wide use of renewable energy technologies for generating electricity can be seen as one way of meeting environmental and climate change challenges along with a progression to a low-carbon economy. A large number of policy instruments have been formed and employed to support the adoption of renewable energy technologies in the power generation sector. However, the success of these policies in achieving their goals relies on how effective they are in satisfying their targets and thus increasing renewable energy adoption. One measurement for effectiveness of policy instruments can be their contribution to the input of the process of renewable energy adoption and their effect on satisfying regional goal. The objective of this research is evaluate the effectiveness of energy policy instruments on increasing the adoption of renewable energy by developing a comprehensive evaluation model. Criteria used in this assessment depend on five perspectives that are perceived by decision makers as important for adoption process. The decision model linked the perspectives to policy targets and various energy policy instruments. These perspectives are: economic, social, political, environmental and technical. The research implemented the hierarchical decision model (HDM) to construct a generalized policy assessment framework. Data for wind energy adoption in the Pacific Northwest region were collected as a case study and application for the model. Experts' qualitative judgments were collected and quantified using the pair-wise comparison method and the final rankings and effectiveness of policy alternatives with respect to the mission were identified. Results of this research identified economic feasibility improvement of renewable energy projects as the most influential perspective and that renewable portfolio standards and tax credits are the two most effective criteria to accomplish that. The research also applied sensitivity analysis and scenario analysis to identify the effect of regional perspectives future priority changes on determining the most effective policy for this perspective. Results showed that renewable portfolio standards and tax credits were found to be the two most effective policies among the alternatives assessed. The research model and outcome can serve as policy check tool in policy making for renewable energy development in any region. Based on the overall research findings, policymakers can apply specific policy instruments to support adoption efforts for any given scenario and regional emphasis.