Die Auswirkungen des EEG auf das Energiesystem Deutschlands – Eine Betrachtung mit dem Energiesystemmodell TIMES-D

In Germany, the electricity generation from renewable energy has been promoted since the year 2000 by a feed-in tariff system, the Renewable Energy Sources Act (EEG). This article evaluates the long-term impact of the German feed-in tariffs on the development of the German energy system with the help of the energy system model TIMES-D. In the model-based analysis, both the payment side (i.e. the tariffs) and the cost side (i.e. the EEG apportionment) are taken into consideration. Through the promotion of the feed-in tariff system—in combination with the European Emission Trading Scheme (ETS)—the use of renewable energies in electricity generation in Germany rises considerably such that renewable energy sources account for almost 40% of total gross electricity consumption in 2030. Accordingly, until 2020 total EEG fee payments as well as the EEG apportionment increase significantly. The impact of the feed-in tariff system on final electricity demand is, however, relatively small. Alternative scenario settings show that the expansion of the renewable electricity generation through the feed-in tariff system clearly exceeds the development which would occur when trying to reach the reduction targets of the ETS in a cost-efficient way.     

Die Verteilung der Kosten des Ausbaus der Erneuerbaren

Germany’s private and industrial consumers have to bear electricity prices that are among the highest in Europe, a major reason being the massive subsidization of green electricity via feed-in tariffs. To dampen future electricity cost increases, numerous suggestions were published recently. They differ substantially with respect to their distributional impacts, transaction costs, political feasibility, and their impact on the cost-effectiveness of the future promotion of renewable technologies. This article’s qualitative evaluation of the most prominent proposals indicates that, more or less, they all fall short with respect to these evaluation criteria. In conclusion, decision-makers would be well advised to reconsider Germany’s renewable energy goals. Consideration should be given to either abolishing these ambitious goals or to improving the cost-effectiveness of the future expansion of renewable energy technologies to dampen the likely continued increase in electricity prices.     

Mögliche Entwicklung der Umlage zur Förderung der Stromerzeugung aus erneuerbaren Energien durch das Erneuerbare-Energien-Gesetz bis 2018

As a result of the strong growth of renewable energies in the German electricity sector within the last few years, the allocation of renewable costs to the consumer (RES-E apportionment) has been set to 5.277 ct/kWh for 2013 (ÜNB, Pressemitteilung der Übertragungsnetzbetreiber zur veröffentlichten EEG-Umlage 2013, 2012a). This article presents potential developments in the costs of promoting renewable energy and the RES-E apportionment in Germany using three different scenarios. Each of the scenarios considers different trends with respect to further deployment of renewable energies, wholesale prices and electricity demand. Due to the underlying uncertainties surrounding these major parameters, the scenarios show a wide range for the RES-E apportionment. A reduction of the RES-E apportionment can be reached if we consider an increase in wholesale prices. However, the scenarios indicate a further increase in the RES-E apportionment, where the amount heavily depends on the further deployment of renewable energies and the development of wholesale prices. Despite the reduction of feed-in tariffs, a main contributor to an increase in the RES-E apportionment is still the ongoing deployment of photovoltaics (PV). In order to prevent a further cost increase without inhibiting renewable targets, it may be worth focusing on comparably cheaper technologies in the further deployment of renewable energies.     

Die Kosten des Klimaschutzes am Beispiel der Strompreise für private Haushalte

Power prices in Germany have been surging since the outset of the new millennium. Among the major reasons for this tendency are newly raised taxes and levies on electricity prices, whose introduction is primarily motivated by climate concerns. Without these taxes and levies, net electricity prices would have remained constant for private households. This article discusses these taxes and levies that have been responsible for the cost increases in private households’ electricity consumption. Most influential have been the feed-in tariffs for renewable energies, above all photovoltaics. According to our calculations, the levy for renewables will further increase in the up-coming years, thereby pushing consumers’ electricity cost once again. Our calculations also show that within the next couple of years, there will be a fierce competition among renewable energy technologies, most notably between photovoltaics and wind power. Politics would be well-advised, therefore, to limit the annual capacity of newly installed solar modules in order to avoid both the explosion of consumers’ electricity bills and strong competition among renewables.     

Prognose der Day-Ahead Wind- und Photovoltaikstromerzeugung – Einflussgrößen und Zuverlässigkeit

In the future, the percentage of renewable energies in the electricity generation is expected to increase continuously. Especially weather-dependent wind and solar power plays a substantial role. These energy sources are partly characterized by a fluctuating and imprecisely predictable power generation. To cover the residual load and to balance the forecast errors a rising number of flexible producers and consumers will be needed in the future. This is necessary to ensure the high security of supply of the German electricity grid.Against this background, the objective of the following investigation is to analyse the day-ahead forecasting quality of the feed-in from wind and photovoltaic systems in the control areas of Germany’s transmission system operators and in the entire area of Germany for the years 2010 to 15. The aim of this analysis is to identify the crucial parameters that influence the forecast error. Subsequently, the share of the wind and photovoltaic power forecast which can be considered as reliably predictable for the following day is estimated. In addition, the increase in this reliable prediction through a higher level of detail in the assessment of the forecast error is quantified. Based on these results, the need of flexibilities through the weather-dependent electricity supply from wind and photovoltaic systems can be estimated, and the impact on the electricity system can be evaluated.     

Gleichzeitigkeit als Leistungsgröße: Inter- und Intra-Klassen-Leistung volatiler EE-Einspeiser

The energy transition focuses on the expansion and enhancement of distribution grids and the integration of decentralized renewable generation plants. The integration of decentralized plants presents a major challenge for distribution system operators in particular. The planning and dimensioning of energy grids requires knowledge of all integrated generating units and power consumers, as well as their power ratings. Furthermore, knowledge about the diversity of renewable power plant types enables distribution system operators and scientists to selectively or cumulatively assess the maximum feed-in capacity. This is particularly important for the assessment of case studies or border scenarios. The purpose of this article is the evaluation of the maximum simultaneous feed-in power of PV and wind power plants. Furthermore, the ratio of the installed power to the maximum power generated by renewable power plants is also investigated. The diversity factor describes the ratio of the sum of all individual load’s maximum powers to the number of loads. This simultaneity can also be adapted to renewable power plants. However, it is differentiated here between simultaneous power within one renewable power plant type (intra-class performance) and simultaneous power of different renewable power plant types (inter-class performance). In cooperation with one of the largest national distribution network operator, regression lines are approximated by statistical analyzes, in order to determinate the diversity of the Central German area.     

Germany’s Energy Supply

Germany has only very limited domestic energy resources. Seventy percent of primary energy needs must be covered by imports. The markets for energy are marked by a wide diversity and a large number of providers. The oil market has been intensely competitive for decades now. Lignite and hard coal are subjected to fierce substitution competition, especially with natural gas. The natural gas and electricity markets were fully liberalized in 1998. Consumers can freely choose from a vast number of suppliers. Since the beginning of this century, however, state interference particularly in the electricity market has increased. The expansion of renewables has been promoted since the year 2000 by feed-in priority and feed-in remunerations regulated by the state. The energy transition initiated in 2011 is characterized by ambitious energy and climate policy targets. Key pillars include the conversion of electricity generation from production on the basis of conventional energy sources to a system based mainly on renewable energies combined with stringent requirements designed to enhance energy efficiency and what are probably the most ambitious climate protection targets worldwide. As regards the expansion of renewables and the phase-out of nuclear energy, Germany is keeping to its target path. By contrast, there are no signs yet that the objectives formulated in terms of the lowering of primary energy consumption and the reduction in greenhouse gas emissions will be achieved.     

Marktwirtschaftliche Energiewende: Ein Wettbewerbsrahmen für die Stromversorgung mit alternativen Technologien

If the German energy transition is to succeed, environmental soundness should not be the only criterion on the agenda with respect to the restructuring of the energy system. It is rather the security of electricity supply and likewise the social sustainability during the transformation process that has to be ensured. The primary question is how to fulfill this challenge in the light of the legal obligation of a complete nuclear power phase-out in the most cost-effective way. The looming avalanche of costs triggered by record-breaking highs of the expanding solar power systems, promoted under the German Renewable Energy Sources Act (EEG), should have made it clear that cost efficiency has only played a minor role so far. According to this study, (real) additional costs for all solar power systems, which had been installed between 2000 and the end of 2011 in Germany, sum up to about 100 billion Euros (prices as of 2011). Since these resources are withdrawn from other societal uses, it is essential that costs for the energy transition in general and in particular the consumers’ costs due to an increased share in renewable energies have to be minimized. For this reason, a new, more cost-efficient and market-oriented promotion/funding system is needed to replace the current system based on the EEG. As suggested by the Monopoly Commission (Monopolkommission 2011), the German Council of Economic Experts (SVR 2011) and recently by acatech, Germany’s National Academy of Science and Engineering (acatech 2012), a market-based promotion system with quantity control in the form of quotas for “green” energy would be a more efficient system. If from 2013 onwards, the future expansion of renewable energies would be fostered by a national quota-based system instead of the EEG, the expansion could be more cost-effective, according to calculations of this study. If, for example, the future price for green electricity certificates exclusively accelerated the expansion of on-shore wind power, the overall subsidies for those wind power capacities that may be installed between 2013 and 2020 merely amount to EUR 6.8 billion (current prices) instead of subsidies in the amount of nearly 58.8 billion Euro (current prices) in the case of further sticking to the EEG. This alone should give sufficient reason to replace the EEG as quickly as possible by a market-based support system such as the quota system.     

Elektroautos in einer von erneuerbaren Energien geprägten Energiewirtschaft

The German Federal Government wants to establish Germany as a leading market for electric mobility. Potential environmental benefits and changes in the economic framework conditions of the energy sector are described in this paper. In order to quantify the electricity split which is actually used for charging electric vehicles, two economic models for the energy sector, a model for the market penetration of electric vehicles, a vehicle model and an LCA model are brought together. Based on an assumed dynamic increase of electric vehicles to 12 million in 2030, an additional electricity demand of about 18 TWh is calculated. If the vehicles are charged directly after their last daily trip, the peak load increases by 12%—despite the small increase in electricity demand. First model calculations for the development of the European power generation system show that the direct impact on the construction of new power plants remains low even until 2030. An impact of electric mobility on CO₂ certificate prices can only be seen from 2025 onwards and is limited to an increase in certificate prices by a maximum of 8 % in 2030. An optimisation is possible with intelligent charging strategies: The peak load without demand side management can be reduced by 5 GW and about 600 GWh of additional wind energy can used which would otherwise have been throttled due to feed-in management—about 3.5 % of the total electricity demand of electric vehicles. On the other hand, demand side management leads to more coal power plants instead of gas power plants being used to meet the additional electricity demand. If additional renewable sources are installed along with demand side management, the electricity for electric vehicles is almost carbon free. This is also reflected in the life cycle balance of electric vehicles which also includes vehicle and battery production: With today’s average electricity split in Germany, the greenhouse gas emissions of electric vehicles are about comparable to vehicles with conventional combustion engines. However, the electricity split in 2030 or the use of additional renewable energy sources lead to a significant advantage in the greenhouse gas balance.     

Can Lignite Take a Back Seat?

Transmission grid extension is a central aspect of the future energy system transition in Germany. This stems from the diverging occurrence of renewable energy feed-in and consumption as well as the targeted nuclear and currently discussed carbon phase-outs. After realizing the retirement of the domestic nuclear energy fleet by 2022, a next policy objective could be the phase-out of domestic lignite generation. The German electricity grid was not designed to accommodate these emerging challenges. Hence, the following paper addresses the impact of decommissioning lignite power plants on the most cost-effective grid extensions by 2030. To determine the optimal transmission grid design, efficient methods for techno-economic analysis are required. The challenge of conducting an analysis of grid extensions involves lumpy investment decisions and the non-linear character of several restrictions in a real-data environment. The following paper introduces the application of the Benders Decomposition, dividing the problem into an extension and a dispatch problem to reduce the degree of computational complexity. The results show that lignite phase-out can significantly increase the number of grid extensions in Germany. All scenarios simulating a lignite phase-out by 2030 lead to higher overall system costs but lower CO\({}_{2}\) emissions.     

Zur Analyse der Auswirkungen der Biomethaneinspeisung auf die Entwicklung der deutschen Erdgasversorgung

Natural gas offers several advantages compared to other fossil fuels, especially regarding its specific CO₂ emissions and its flexibility in usage. Thus, it is expected that the consumption of natural gas will further increase in the future. Nevertheless, this increase is accompanied by a growing dependence on imports. Biomethane, i.e. conditioned biogenous gas, is an interesting possibility for the substitution of natural gas. As it is a renewable and indigenous energy source, it contributes to the reduction of both: CO₂ emissions and gas imports. Similar to the renewable electricity generation, the German government sets targets for the biomethane feed-in and has introduced promotion mechanisms to achieve these goals. Within this paper the possible role of biomethane in the German natural gas supply has been evaluated by applying the optimising energy flow model PERSEUS-EEM. Results show that the CO₂ emissions trading system by itself is not sufficient for the competitiveness of biomethane. Model results demonstrate that a significant increase of the German natural gas demand can be expected especially due to the stringent CO₂ reduction targets. Even when the political CO₂-reduction targets are reached, biomethane will not play a major role in the natural gas supply of Germany.     

Ökonomische Bewertung des Repowering von Onshore-Windenergieanlagen in Deutschland

Wind power takes a leading role among the renewable energy sources. Whereas in offshore wind power utilization large technical challenges still need to be tackled for commercial exploitation, the replacement of obsolete plants (repowering) in the onshore sector provides an interesting alternative. This paper first provides an overview of the technical, legal and social development concerning wind power utilization in general, and repowering in particular, in Germany. In a next step, by means of model-based analysis, the technical potential for wind power by means of repowering is determined. The theoretical potential is valuated against social aspects. Due to the large heterogeneity of candidate sites for repowering, general potential studies are not suitable for concrete investment decisions. Instead, a detailed economic feasibility study is required. In our study, we performed scenario analysis, also taking into account the repowering-specific risks. The parameter values varied are those for the quality of the site, the size of the wind park, and the age of the wind turbines to be replaced. Finally, we discuss the results and provide an outlook on the development of repowering in light of the novelized EEG. We find that, until now, the repowering potential could not be fully exploited. An intensified realization of repowering projects in the coming years can be expected, due to the technical potential, simplifications in the commissioning process, rising acceptance on the side of the communities due to changes in the tax legislation and, above all, thanks to the incentives for almost all onshore wind parks.     

Zur Akzeptanz von Stromspeichern in Unternehmen

The German Energy Transition challenges the German Energy System with the integration of renewable energy and its mainly fluctuating nature (especially wind and PV-energy). In order to balance energy demand and supply scholars critically discuss decentralized electric energy storages as an option to introduce more flexibility to the system. In an industrial setting electric energy storage solutions are especially of interest to implement load management, meaning a temporal deferral of load capacity, for peak-shaving activities and the possibility to achieve higher consumption rates of self-generated electricity. One question arises: What do companies think about the use of energy storage solutions in their companies as of today? This article offers an empirical starting point in looking further into detail concerning the overall attitude and the level of knowledge with regard to electrical energy storage solutions based on guided interviews with companies of the manufacturing and processing industry in Germany.     

Ein Jahr danach: Erste empirische Ergebnisse der Ausschreibungen für Windenergie an Land gemäß EEG 2017

The sixth amendment of the German Renewable Energy Sources Act (Erneuerbare-Energien-Gesetzes [EEG]) came into force at January 1st, 2017. Especially regarding onshore wind energy, it includes fundamental changes. Having set raised market integration as well as market compatibility and cost-efficiency as the main three goals, market-based tendering shall be the instrument to reach them.Meanwhile, the first three calls have been completed. This enables the opportunity for a first evaluation of the tendering as a system to fund onshore wind energy in Germany and a comparison of the criticism which came along with the newest amendment. At first glance, several improvements can be found: Especially a—previously expected—forced competition on the market but also low bid and tender values show a massive potential of cost reduction. However, the analysis further shows that energy cooperatives are disproportionally privileged, which leads to a distortion of competition and the risk of a future non-continuous development. Additionally, the current system results in regional disparities, coming along with disadvantages especially for the southern states. 10 suggestions for improvement show possible answers concerning the main shortcomings.