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[en] Geothermal energy is a topic much discussed for its merits in terms of energy and environment. One application option may be the utilization of thermal waters of 40-100 C temperature for heating rooms and domestic/industrial water in Northeastern Germany. The use of the geothermal energy potential of thermal waters, however, depends from the existence of appropriate geological conditions like horizon, reservoir, temperature and chemistry. The experience gained in East Germany, indicates that any decision to be taken for the utilization of geothermal energy needs to be based on an in-depth analysis of the geological conditions down to 2,000 m and below by means of deep drilling and mining exploration. (BWI)
[de]Erdwaerme hat im Rahmen der Energie- und Umweltdiskussion einen zunehmenden Stellenwert erhalten. Eine Moeglichkeit ist die Nutzung niedrigthermaler Tiefenwaesser im Temperaturbereich von 40-100 C fuer Raumwaermeerzeugung und Gebrauchswarmwasserbereitung in Nordostdeutschland. Voraussetzung fuer die Nutzung des an Thermalwaesser gebundenen geothermischen Energiepotentiales ist die Existenz entsprechender geologischer Bedingungen, wie Naturhorizont, Nutzreservoir, Temperatur und chemische Eignung. Die ostdeutschen Erfahrungen zeigen, dass fuer die Entscheidung ueber eine Nutzung geothermischer Energie eine gruendliche Analyse der geologischen Verhaeltnisse im Untergrund bis 2.000 m und darunter auf der Basis von Tiefbohrungen und bergmaennischen Aufschluessen vorgenommen werden muss. (BWI)
[en] The German Federal Government published its energy concept in September 2010 with a description of the road into the era of renewable energies. Therefore, the future renewable energy installed in Germany is expected to consist mostly of wind and solar, which are subject to intermittency of supply and significant fluctuations. The growing portion of energy generation by fluctuating sources is turning to a big challenge for the power plant unit commitment and the investment decisions as well. In this thesis, a fundamental electricity market model with combined modeling of these two aspects is developed. This model is subsequently applied to the German electricity market to investigate what kind of power plant investments are indispensable, considering the steadily increasing portion of energy generation from fluctuating sources, to ensure a reliable energy supply in a cost-effective way in the future. In addition, current energy policy in Germany regarding the use of renewable energy and nuclear energy is analyzed.
[en] Variable renewable energy sources (VRE) for electricity generation, such as wind and solar power, are subject to inherent output fluctuations. This variability has significant impacts on power system and electricity markets if VRE are deployed at large scale. While on global average, wind and solar power currently supply only a minor share of electricity, they are expected to play a much larger role in the future - such that variability will become a major issue (which it already is in some regions). This thesis contributes to the literature that assesses these impacts the ''system and market integration'' literature. This thesis aims at answering the question: What is the impact of wind and solar power variability on the economics of these technologies? It will be laid out that the impact can be expressed in (at least) three ways: as reduction of value, as increase of cost, or as decrease of optimal deployment. Translating between these perspectives is not trivial, as evidenced by the confusion around the concept of ''integration costs''. Hence, more specifically: How does variability impact the marginal economic value of these power sources, their optimal deployment, and their integration costs? This is the question that this thesis addresses. This study comprises six papers, of which two develop a valuation framework that accounts for the specific characteristics of the good electricity, and the specific properties of wind and solar power versus ''dispatchable'' power plants. Three articles then assess quantitative questions and estimate marginal value, optimal deployment, and integration costs. These estimates stem from a newly developed numerical power market model, EMMA, market data, and quantitative literature reviews. The final paper addresses market design. In short, the principal findings of this thesis are as follows. Electricity is a peculiar economic good, being at the same time perfectly homogenous and heterogeneous along three dimensions - time, space, and lead-time. Electricity's heterogeneity is rooted in its physics, notably the fact it cannot be stored. (Only) because of heterogeneity, the economics of wind and solar power are affected by their variability. The impact of variability, expressed in terms of marginal value, can be quite significant: for example, at 30% wind market share, electricity from wind power is worth 30-50% less than electricity from a constant source, as this study estimates. This value drop stems mainly from the fact that the capital embodied in thermal plants is utilized less in power systems with high VRE shares. Any welfare analysis of VRE needs to take electricity's heterogeneity into account. The impact of variability on VRE cannot only be expressed in terms of marginal value, but also in terms of costs, or in terms of optimal deployment. The mentioned value drop corresponds to an increase of costs by 30-50%, or a reduction of the optimal share by two thirds. These findings lead to seven policy conclusions: 1. Wind power will play a significant role (compared to today). 2. Wind power will play a limited role (compared to some political ambitions). 3. There are many effective options to integrate wind power into power systems, including transmission investments, flexibilizing thermal generators, and advancing wind turbine design. Electricity storage, in contrast, plays a limited role (however, it can play a larger role for integrating solar). 4. For these integration measures to materialize, it is important to get both prices and policies right. Prices need to reflect marginal costs, entry barriers should be tiered down, and policy must not shield agents from incentives. 5. VRE capacity should be brought to the system at a moderate pace. 6. VRE do not go well together with nuclear power or carbon capture and storage - these technologies are too capital intensive. 7. Large-scale VRE deployment is not only an efficiency issue, but has also distributional consequences. Re-distribution can be large and might an important policy driver.
[en] The paper shows that the renewable energy sources offer a unique chance: to replace the 'deus ex machina' philosophy by the 'deus ex sole' approach. The reasons why the energy industry refuses to consider exploitation of renewable energy sources are quite obvious. Any deep-cutting change in energy policy priorities would imply likewise deep cuts in the utilities' returns from investments made for existing, conventional power generation systems and transmission infrastructure, which would entail losses in a branch of industry never seen before. It is high time, however, to demand a basic switch in policy and to pave the way for solar energy by appropriate political and economic incentives now, as Germany as one of the highly industrialised countries must not turn a blind eye to its responsability for the global environment. Even if there were not the risk of a global environmental crisis as a consequence of current resource squandering, good economic reasoning and a sense of responsability for the developing economies of the world be reason enough to alter the energy policy approach without hesitation. (orig./CB)
[de]Wie dargestellt wird, sind die erneuerbaren Energien eine einzigartige Chance: Kein 'deus ex machina', sondern ein 'deus ex sole'. Es ist nachvollziehbar, warum sich die Energiewirtschaft in einer breiten Ablehnungshaltung befindet. Ihre Investitionen in die herkoemmlichen Energietraeger und in die darauf zugeschnittenen Versorgungsstrukturen stehen bei einem grundlegenden energiepolitischen Prioritaetenwechsel in einem Ausmass zur Disposition, wie es bei keinem Wirtschaftszweig bisher auch nur annaeherend der Fall war. Gefordert wird, dass der Durchbruch zur Nutzung solarer Energiequellen jetzt erfolgen muss, indem wir eine Dynamik zu ihrer Nutzung entfachen und dabei nicht zuletzt unsere weltwirtschaftliche Verantwortung wahrnehmen, der wir uns als fuehrendes Industrieland mit Vorbildfunktion nicht entziehen duerfen. Selbst wenn es die globale Umweltkrise durch herkoemmlichen Energieeinsatz nicht gaebe, muessten wir aus Gruenden oekonomischer Vernunft und der Mitverantwortung fuer die wirtschaftliche Entwicklung der Dritten Welt diesen Weg unverzueglich gehen. (orig.)
[en] Ongoing climate change affects complex and long-lived infrastructures like electricity systems. Particularly for decarbonized electricity systems based on variable renewable energies, there is a variety of impact mechanisms working differently in size and direction. Main impacts for Europe include changes in wind and solar resources, hydro power, cooling water availability for thermoelectric generation and electricity demand. Hence, it is not only important to understand the total effects, i.e., how much welfare may be gained when accounting for climate change impacts in all dimensions, but also to disentangle various effects in terms of their marginal contribution to the potential welfare loss. This paper applies a two-stage modeling framework to assess RCP8.5 climate change impacts on the European electricity system. Thereby, the performance of two electricity system design strategies - one based on no anticipation of climate change and one anticipating impacts of climate change - is studied under a variety of climate change impacts. Impacts on wind and solar resources are found to cause the largest system effects in 2100. Combined climate change impacts increase system costs of a system designed without climate change anticipation due to increased fuel and carbon permit costs. Applying a system design strategy with climate change anticipation increases the cost-optimal share of variable renewable energy based on additional wind offshore capacity in 2100, at a reduction in nuclear, wind onshore and solar PV capacity. Compared to a no anticipation strategy, total system costs are reduced.
[en] With strict impartiality and neutrality, the Georg Michael Pfaff Foundation is of the opinion that all nuclear power stations should be rapidly shut down and the solar energy programme supported for years by the Foundation should be supported by technically possible energy savings. Basic questions of the following type must be decided: Is it permissible to ignore rights and the claims of future generations, in order to satisfy the short term needs of one generation. Are those alive now entitled to leave obligations for their children and grandchildren, which they cannot decide for themselves and which, if they had had the choice, they would never have accepted, in all probability. (orig./HSCH)
[de]Bei strikter Ueberparteilichkeit und Neutralitaet ist die Georg Michael Pfaff Gedaechtnisstiftung der Meinung, alle Kernkraftwerke beschleunigt abzuschalten und gemaess den seit Jahren von ihr vertretenen Prinzipien die Sonnenenergie zu forcieren, unterstuetzt durch technisch ermoeglichte Energieeinsparung. Zur Entscheidung stehen Grundsatzfragen solcher Art: Ist es erlaubt, sich ueber Recht und Anspruch kommender Geschlechter hinwegzusetzen, um den kurzfristigen Nutzen einer einzigen Generation zu mehren. Sind die jetzt Lebenden dazu befugt, Kindern und Enkeln Verpflichtungen zu uebertragen, fuer die sie sich nicht selbst entscheiden konnten und die sie, haetten sie die Moeglichkeit zur Wahl gehabt, wahrscheinlich niemals eingegangen waeren. (orig./HSCH)
[en] The Commission wants especially to give preference to the measures concerning improved energy utilization and energy conservation in the following 10 years; it wants, in some way, the making up of conservation techniques to be taken for granted as opposed to the expansion of nuclear energy utilization. In addition to this rather general recommendation a majority vote was made for those famous '62 recommendations of action'. It must be assumed that the public shall be convinced that there is a further demand for nuclear power plants only if anything has been made to close the supply gaps by using energy sources like conservation and solar energy. (orig./HSCH)
[de]Die Kommission moechte, insbesondere fuer die naechsten 10 Jahre, den Massnahmen zur verbesserten Energienutzung, zur Einsparung von Energie Vorrang einraeumen, sie moechte gewissermassen ein Nachholen der Einspartechniken gegenueber dem Ausbau der Kernenergienutzung garantiert sehen. Zusaetzlich zu dieser immer noch sehr allgemein gehaltenen Empfehlung wurden dann mehrheitlich jene beruehmten '62 Handlungsempfehlungen' formuliert. Auch die Oeffentlichkeit wird sich vermutlich nur insoweit davon ueberzeugen lassen, dass ein Bedarf fuer den Zubau von Kernkraftwerken besteht, wie alles getan worden ist, um Bedarfsluecken durch die Nutzung der Energiequellen Einsparung und Sonnenenergie zu schliessen. (orig./HSCH)
[en] In the present article it is studied, under which boundary conditions the application of photovoltaics-based cooling systems is presently economically meaningful. A comparison with a net-drived cold-water set (100 kW_r 5000 full hours/year) as reference system is made. As influence quantity the levelized cost of cooling energy (LCCE) is defined. Following options were studied: - PV system is directly conducted to the cooling facility by means of physical cable connection - PV system is separately fed into the current network and payed back via feeding compensation. Additionally sensitivity analyses of selected parameters on the refrigeration costs were studied.