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Energy demand of continents, countries, communities and individuals will continue to increase in the phase of increasing population and improvement in the living standards of people. The attempt to meet this ever increasing demand and at the same time protect the environment has resulted in the fast growth of power generation from renewable sources of energy especially from wind through wind power plants and solar through photovoltaic power plants. This growth has been facilitated by various support schemes such as feed-in-tariff scheme, feed-in-premium and quota scheme. Further growth is expected in the future. This is because of the existing support schemes and the expectation of the emergence of improved technologies for harvesting renewable energy.
This development of power generation from renewable sources of energy although positive lead to some distinctive negative effects on the existing electrical network to which they are connected. These negative effects are known and well documented. The fluctuating nature of wind and solar radiation at any given location over a given period of observation is seen to translate into the power they feed into the power network. This fluctuating infeed requires more active management of the network by system operators so as to ensure continuous reliable power generation and delivery. Sometimes the management process lead to non-utilization of power produced by the renewables sources. Secondly, expansion and reinforcement of some existing networks are needed in other to accommodate renewable power generators. These come at a cost. Many studies and researches have been dedicated to finding solutions to these issues.
This work agrees with the use of storage systems as means of solving these issues but the question that remains unanswered is what the optimal way is. There is also a further push given to the view of installing renewable energy plants together with storage systems as a unit in this work. The main task presented in this work, however, is a concept of sizing renewable energy plant and storage systems as a unit. The resulting renewable energy plant-storage unit has the objective of supporting the electrical network to which it will be connected. Firstly the support should be by reducing the fluctuating effect from renewable production. Secondly by helping improve the load hosting capacity of the electrical network. This will be by supplying the part of the load demand leading to the reduction of the overall power drawn by connected loads from the electrical power network.
Historic data of renewable resource and also the load demand at the point or bus of connection are the drivers of this concept. With the earlier mentioned objectives and random or stochastic nature of data involved, particle swarm optimization method is employed in implementing the concept of sizing to arrive at an optimal solution of required sizes of the renewable energy plant-storage system.
The concept of sizing is based on proposing an ideal load demand that can be supplied by a utility under normal operating condition at all time. It follows that any extra demand should be supplied by the optimally sized renewable energy plant-storage unit. In this work sizing results of three scenarios presented. A single node network with three different types of the load was used in testing the effect of optimally sized renewable energy plant-storage system on an electrical network. The outcome of this test showed that the optimally sized renewable energy storage-system improved the ability of the test electrical network to support additional load hence load hosting capacity of test network was improved. The process required modelling and simulation all of which were carried out using MATLAB Simulink software.
Die “Energiewende” wird in der vorliegenden Arbeit als umfassender gesellschaftlicher Prozess aus soziologischer Perspektive untersucht. Da die Vorreiter der Entwicklung bisher in geographischen und damit auch sozialen Nischen zu finden sind, wurden sieben möglichst weit fortgeschrittene und ambitionierte „Energieregionen“ im ländlichen Raum als Fallstudien ausgewählt. Das Paradigma der Energieautarkie oder der 100% Region wurde dabei als Leitbild eines noch jungen Entwicklungspfades mit Hilfe qualitativer Methoden untersucht. Unter Energieautarkie (oder Energieautonomie) wird das Ziel verstanden, eine Region vollständig durch erneuerbare Energieproduktion mit Wärme und Elektrizität zu versorgen. Dies ist aufgrund der hohen Anforderungen bisher selten vollständig realisiert worden. Die vorliegende Arbeit beschreibt die Hindernisse, Entwicklungsstufen und typischen Probleme sowie die Faktoren, welche ihre Bewältigung ermöglichen. Im Vergleich der Fallstudien wird ein theoretisches Modell entwickelt, um den Erfolg einzelner Initiativen erklären und in gewissem Umfang vorhersagen zu können. Daraus wird die These abgeleitet, dass sich die technische und ökonomische Infrastruktur erneuerbarer „Energieregionen“ langfristig der Sozialstruktur anpasst und die Diffusion weiterer „Energieregionen“ vom gegebenen Niveau des Sozialkapitals bedingt wird. Aufgrund der gegenseitigen Abhängigkeit sozialer und technischer Komplexitätsniveaus bedeutet die Energiewende für den ländlichen Raum in erster Linie eine soziale und organisatorische Herausforderung. Die vorliegende Arbeit beschreibt die verschiedenen Strategien der beteiligten Akteure und ihre Konstellationen.
Cameroon has vast renewable energy resource potentials, with a hydropower potential of about 55,200MW, second only to the Democratic Republic of Congo in Africa. So far, its energy needs are met by 4.8% hydropower (which accounts for less than 5% of its total hydropower potential), 0% wind and 0% solar. Cameroons’ energy sector still goes through insufficient electrical energy production, especially during the heart of the dry season, which runs from December through March. Coincidentally, the wind and solar power potentials for Cameroon are at their peak during these months and could conveniently supplement for the shortfalls in generation during these periods. In this research, technical analysis were carried out to determine the wind and solar energy resource potentials for Cameroon using the RETScreen software tool provided by CANMET Canada. These analysis revealed that the northern regions of Cameroon had higher wind and solar resource potentials than any other location in Cameroon. A 2MW installed wind energy capacity would be capable of generating well over 1.5GWh electrical energy per year, while a 2KW installed solar energy capacity will be capable of generating well over 3MWh electrical energy per year. In the final sections, financial analysis were carried out to determine the economic viability of such projects and the possibility for self-financing. Emission analyses were also done based on the ability for such projects to offset greenhouse gas emissions and ensure sustainability in the energy sector. The analysis for Maroua revealed that 78.6tCO2/yr for wind and 0.1tCO2/yr for solar could be reduced by those installations. Finally, the legislations and legal frameworks governing the energy sector in Cameroon were dissected to determine possible weaknesses and constraints limiting the use, promotion and development of the full potential of Cameroon’s renewable energy resources.
Möglichkeiten und Grenzen der Nutzung erneuerbarer Energieträger am Beispiel des Landes Brandenburg
(2004)
Ziel der Arbeit war die Entwicklung eines energiewirtschaftlichen Modells, um künftige Entscheidungen zum Ausbau der regenerativen Energieträger nach unterschiedlichen, sich teilweise widersprechenden Kriterien treffen zu können. Das Modell ist für die strom- und wärmeseitige Energiebereitstellung anwendbar. Neben der Berücksichtigung aller energiewirtschaftlicher Aspekte wurde in den Modellrechnungen jeweils der gesamte Lebenszyklus „life cycle“ einer Anlage erfasst. In dem Modell sind Berechnungen sowohl mit frei wählbaren Schwerpunktsetzungen, wie beispielsweise vorhandenes Potenzial, ökologische Aspekte und Wertschöpfung als auch Rechenoperationen ohne jede Wichtung möglich. Die Funktionsfähigkeit des Modells wurde anhand der Kennzahlen für das Land Brandenburg nachgewiesen. Bei den Schlussfolgerungen aus den Modellrechnungen konnten eindeutige Aussagen und Empfehlungen für den künftigen Einsatz der jeweiligen regenerativen Energieträger getroffen werden.