Zukünftige Energie- und Industriesysteme
In this paper a new method for the evaluation and comparison of potential future electricity systems is presented. The German electricity system in the year 2050 is used as an example. Based on a comprehensive scenario analysis defining a corridor for possible shares of fluctuating renewable energy sources (FRES) residual loads are calculated in a unified manner. The share of electricity from PV and wind power plants in Germany in the year 2050 is in a range of 42-122% and the load demand has a bandwidth of around 460-750 TWh. The residual loads are input for an algorithm that defines a supplementary mix of technologies providing flexibility to the system. The overall system layout guarantees the balance of generation and demand at all times. Due to the fact that the same method for residual load calculation and mixture of technologies is applied for all scenarios, a good comparability is guaranteed and we are able to identify key characteristics for future developments. The unique feature of the new algorithms presented here is the very fast calculation for a year-long simulation with hourly or shorter time steps taking into account the state of charge or availability of all storage and flexibility technologies. This allows an analysis of many different scenarios on a macro-economic level, variation of input parameters can easily be done, and extensive sensitivity analysis is possible. Furthermore different shares of FRES, CO2-emission targets, interest rates or social acceptance of certain technologies can be included. The capabilities of the method are demonstrated by an analysis of potential German power system layouts with a base scenario of 90% CO2-reduction target compared to 1990 and by the identification of different options for a power sector with a high degree of decarbonisation. The approach also aims at a very high level of transparency both regarding the algorithms and regarding the input parameters of the different technologies taken into account. Therefore this paper also gives a comprehensive and complete overview on the technology parameters used. The forecast on all technologies for the year 2050 regarding technical and economic parameters was made in a comprehensive consultation process with more than 100 experts representing academia and industry working on all different technologies. An extensive analysis of options for the design of potential German energy supply systems in 2050 based on the presented methodology will be published in a follow-up paper.
Technologischer Wandel ist wichtig für die Umsetzung und den Erfolg der Energiewende, deswegen strebt die Bundesregierung mit ihrer Politik auch eine positive Innovationswirkung an. Doch welche Auswirkungen hat der politisch angestoßene Wandel des Energiesystems wirklich und welche Dynamiken werden durch ihn induziert? Eine aktuelle Studie untersucht die Sicht auf die Energiepolitik und Innovationsaktivitäten in der Energiewirtschaft und Energietechnologie-Branche. Sie zeigt die durch die Energiewende getriebenen Innovationsdynamiken, aber auch Schwierigkeiten und Herausforderungen für Politik und Unternehmen auf.
Die Transformation des deutschen Energiesystems in Richtung signifikanter Reduktion energiebedingter CO2-Emissionen kann durch eine Abfolge verschiedener Phasen beschrieben werden. Phasenübergänge ergeben sich dabei aus strukturellen Erfordernissen im Gesamtsystem bei kontinuierlichem weiteren Ausbau erneuerbarer Energiewandler, insbesondere Sonne und Wind. Die anstehende zweite Phase ist durch eine umfassende Systemintegration volatiler erneuerbarer Energien insbesondere im Bereich der Strombereitstellung geprägt. Dies erfordert sowohl eine flexible komplementäre Erzeugung als auch die Aktivierung von Flexibilitätsoptionen auf der Verbrauchsseite.
Die Landesregierung in NRW hat am 14.4.2015 den in einem aufwändigen Stakeholderprozess erstellten Klimaschutzplan vorgestellt. Eines der Ziele war, die Klimaschutzpolitik als langfristige Strukturpolitik zu implementieren und entsprechende Prozesse in die Breite der Gesellschaft zu tragen. Weitere Bundesländer und der Bund selbst haben inzwischen ähnliche Prozesse eingeleitet. In zahlreichen anderen Ländern gibt es Beschlüsse, die in diese Richtung gehen. Eine Übersicht über den Prozess der Planerstellung in NRW und über den Stand der Diskussion in Deutschland verdeutlicht, wie Klimaschutzpläne durch partizipatorische Elemente in der Erstellungsphase mehr Akzeptanz erfahren können.
At current primary steel production levels, the iron and steel industry will fail to meet the 80% emission reduction target without introduction of breakthrough technologies (Wörtler et al., 2013: 19). The current research analyses the technical and economical long-term potential of innovative primary steel production technologies in Germany throughout 2100. Techno-economic models are used to simulate three innovative ore-based steelmaking routes verses the reference blast furnace route (BF-BOF). The innovative routes in focus are blast furnace with CCS (BF-CCS), hydrogen direct reduction (H-DR), and iron ore electrolysis (EW). Energy and mass flows for the production of one tonne of crude steel (CS) are combined with hypothetical price, cost, and revenue data to evaluate the production routes economically, technically, and environmentally. This is a purely theoretical analysis and hence further external factors that may influence practical implementation or profitability are not considered.
Different future developments are considered by using three scenarios, representing an ambitious, a moderate, and a conservative transformation of the German energy sector. In general, looking into the future bares various uncertainties which should be reflected in a suitable manner.
According to the present scenario analysis, chances are that with rising prices for coal and CO2 allowances BF-BOF and even BF-CCS become unprofitable by mid-century. With a high share of renewable energy sources and high prices for CO2 allowances, H-DR and EW become economically attractive in the second half of the current century, when BF-based routes are long unprofitable. Energy and raw material efficiency is significantly higher for H-DR and EW and furthermore, the 80% reduction target by 2050 can be achieved in the ambitious scenario. However, high investment costs and high dependency on electricity prices prohibit a profitable implementation before 2030–2040 without further subsidies. EW is the most energy and resource efficient production route. Since continuous electricity is needed for the continuous operation, the electricity costs are 20–40% higher than for H-DR (with high-capacity hydrogen storage units). Even though hydrogen production implies efficiency losses compared to the EW route, the decoupling of hydrogen production from continuous operation of the steel plant through hydrogen storage offers the opportunity to use cheap excess renewable electricity. This makes the H-DR economically and environmentally the most attractive route and provides a crucial contribution to stabilize the grid and to store excess energy in a 100% renewable energy system.
In recent decades, better data and methods have become available for understanding the complex functioning of cities and their impacts on sustainability. This review synthesizes the recent developments in concepts and methods being used to measure the impacts of cities on environmental sustainability. It differentiates between a dominant trend in research literature that concentrates on the accounting and allocation of greenhouse gas emissions and energy use to cities and a reemergence of studies that focus on the direct and indirect material and resource flows in cities. The methodological approaches reviewed may consider cities as either producers or consumers, and all recognize that urban environmental impacts can be local, regional, or global. As well as giving an overview of the methodological debates, we examine the implications of the different approaches for policy and the challenges these approaches face in their application on the field.
Die Entscheidung für ein von volatilen Erzeugungsquellen dominiertes Stromsystem stellt an die Stabilisierung des Systems neue Anforderungen. Zugleich bieten sich neue Optionen. Die bisherige Asymmetrie, nach der für die Stabilisierung die Kraftwerksseite verantwortlich sei, ist überkommene Praxis, deswegen auch heute habituell naheliegend, aber vermutlich nicht länger effizient. Die im Titel genannten nachfrageseitigen Ausgleichsoptionen (SE & DSM) bieten sich an. Im Beitrag wird deren Potential abgeschätzt. In vier Gestaltungsfeldern wird zudem gefragt, ob die bislang von der Politik gegebenen rechtlichen Mandate konsequent SE & DSM als Option berücksichtigen. Das Ergebnis ist viermal (weitgehende) Fehlanzeige.
The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO2 reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO2 storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered–that is the capture of CO2 at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.
The energy potential of agricultural residues in Tanzania has so far not been evaluated and quantified sufficiently. Moreover, the scientific basis for estimations of the sustainable potential of wastes and residues is still very limited. This paper presents an attempt to evaluate the theoretical and technical potential of residues from the sisal sector in Tanzania with regards to energy recovery through anaerobic digestion. The characteristics and availability of sisal residues are defined and a set of sustainability indicators with particular focus on environmental and socio-economic criteria is applied. Our analysis shows that electricity generation with sisal residues can be sustainable and have positive effects on the sustainability of sisal production itself. All sisal residues combined have an annual maximum electricity potential of 102 GW h in 2009, corresponding to up to 18.6 MW of potential electric capacity installations. This estimated maximum potential is equivalent to about 3 % of the country's current power production. Utilizing these residues could contribute to meeting the growing electricity demand and offers an opportunity for decentralized electricity production in Tanzania.
Mit dem Kernenergieunfall im japanischen Fukushima im März 2011 ist die Diskussion über das Für und Wider der Nutzung der Kernenergie für die Stromerzeugung in Deutschland neu entbrannt. Die Frage nach den Auswirkungen eines beschleunigten Ausstiegs aus der Kernenergienutzung auf die Entwicklung der Strompreise in Deutschland bildete in den vergangenen Monaten einen Schwerpunkt der öffentlichen Diskussion. Allerdings halten nicht alle Aussagen, die hierzu veröffentlicht wurden, einer kritischen Analyse stand, was zum Teil auch an zugrunde liegenden politischen Motiven gelegen haben mag. Eine Untersuchung fundierter Studien und ausgewählter Stellungnahmen zeigt, dass sich die befürchteten kurzfristigen Preiseffekte in ü̈berschaubaren Grenzen halten werden.