Stromspeicher für die „Energiewende“ – eine akteursbasierte Analyse der zusätzlichen Speicherkosten

Political targets for implementing the German “energy turnaround” aiming at the ambitious extension of renewable energies to generate electricity. However, a majority of the renewable supply is provided by intermittent sources, e.g. wind and solar power. For balancing the increasing supply fluctuations additional storage options are claimed beside of an enforced grid infrastructure and a more flexible demand side. Despite of the political guidelines the economics of additional flexibility measures has to be considered. For this paper we analyse the costs of large scale stationary battery storages to be operated in wholesale markets and transmission grid level. By deriving a key figure based on a life-cycle cost approach, we are able to evaluate the additional costs of electricity of selected battery technologies (lead-acid, lithium ion, sodium sulphur, redox-flow). Moreover, current and valid parameters of the cost analysis are received by scientific and industrial stakeholders of battery systems via online survey and face-to-face interviews. According to the stakeholder estimation a nationwide operation of stationary battery storages will be established at wholesale and transmission grid level until the year 2030. The life-cycle cost analysis, which also includes estimated future cost reductions, shows that lead-acid batteries remain the cost-efficient technology, assuming about 100 storage cycles p.a. In addition, a sensitivity analysis reveals the impact of increasing annual storage cycles as well as the achievable cost reduction by economies-of-scales of the power unit of the storage system.     

Grosse Stadtwerke – theoretische und empirische Exploration eines besonderen Akteurs in der Energiewende Deutschlands und der Schweiz

Urban utility companies are key players in the Swiss and German energy sector. Due to the federalist and subsidiary governance structure of the two countries’ energy sector, they perform highly system relevant tasks, as e.?g. managing the distribution grids or ensuring the public services for “their city”. In the public and scientific discourse on the role of different actor groups in the energy transition, however, not much attention is paid to urban utility companies. This contribution aims at a theoretical and empirical exploration of these particular actors by analysing their characteristics, specific challenges and strategic answers in the context of the energy transition. For this purpose, the article derives analytical dimensions for the analysis of urban utility companies from scholarly literature on transition studies, network industries and public corporate governance and empirically analyses characteristics and the current situation of urban utility companies in Germany and Switzerland. Methodologically, this article is based on an explorative, qualitative study, which synthesises results from a literature analysis, a document analysis, 38 expert interviews in both countries (in 2017) and two expert workshops conducted in Switzerland (in 2018). The study shows, how the characteristics of urban utility companies can be explained based on public corporate governance and network industries literature. This also allows to identify and understand their particular challenges, as e.?g. the fields of tension among public and private interest in the firms and the multi-dimensional relationship of owner or the particularities of network industries. Finally, this article points out, that the role of urban utility companies in the Swiss and German energy transition is neither just “inhibitor” nor pure “innovator”, but can be labelled as “intelligent follower” and “engineer of the energy transition”.     

Energiewende und Übertragungsnetzausbau: Sind Erdkabel ein Instrument zur Steigerung der gesellschaftlichen Akzeptanz des Leitungsbaus? Eine empirische Untersuchung auf Basis der Kontingenten Bewertungsmethode

Transmission network development has led to protests throughout Germany. Many studies present underground cables as a means to increase public agreement to transmission line construction and network development. This paper verifies this thesis analyzing the willingness-to-pay of private households for underground cable employment, which allows for a distinct analysis of strategic behavior and opportunity costs that is omitted in classic questionnaire designs. The results of a contingent valuation study conducted in November and December 2012 in four regions of Germany, which are affected by transmission line development in different ways, are presented. At first glance, an analysis of 1.003 household responses confirms common findings with a majority of households favoring underground cables (about 60 %), albeit preferences vary strongly between sample regions. Willingness-to-pay, however, relativizes this result. A near share of 50 % of households voting for underground cables is not willing to accept an increase in electricity prices to finance respective projects (free riders). The fact that positive willingness-to-pay does not correlate positively with increasing lengths of underground cables in 60 % of cases underlines that underground cables are not supported unconditionally. All-in-all, a flat public approval of underground cable technology cannot be presumed based on WTP-evaluation. Preferences about underground cables and corresponding WTP are explained with demographic characteristics and attitudes using regression models. Fundamental thoughts on energy- and environmental policies do not serve to explain responses. Instead, regional factors and subjective opinions on how to finance such kind of infrastructure measures influence preferences for underground cables.     

?konometrische Analyse der Temperaturvariabilit?t

This paper aims at analysing temperature fluctuations by applying an econometric methodology. To this end a physically founded macroclimate model is suggested for individual examinations of the climate forcing of carbon dioxide (CO₂), methane (CH₄) and other greenhouse gases as well as of the cooling effect of sulphur dioxide (SO₂) since 1880 and for a comparison of their impacts. The autoregressive process in the temperature anomalies is analysed, and a cointegration analysis is carried out to show that a long-term causal interrelation can be derived from the stochastic trend variables considered. However, this interrelation is not unique. It turns out that anthropogenic factors and total solar irradiance determine the warming trend in the period 1880 to 2005, whilst the remaining natural factors explain a part of the deviation from this trend. With 42?% the autoregressive process in the anomalies has a considerable impact on the temperature increase. Climate sensitivity amounting to 0.11 (K?m²)/W therefore is comparatively low. If the share of the autoregressive process is allocated to each regressor individually CO₂ has an impact of 65?%. The SO₂ emissions have a significant cooling effect, neutralizing 45?% of the climate forcing of CO₂. The non-CO₂ greenhouse gases contribute 55?% to the temperature increase and hence more than the net effect of CO₂ and SO₂ of 36?%. Hence, the sensitivity of the climate with regard to these greenhouse gases is very high. When applying accelerated mitigation measures with respect to non-CO₂ greenhouse gases it is possible to reach the 2^° target without decarbonisation.     

Wettbewerbsfähigkeit der Photovoltaik im deutschen Energiemix – Neudefinition des Ansatzes der Netzparität

Photovoltaics are one of the fastest growing energy sources in the world. Despite high costs and a limited energy yield, attractive support schemes particularly the German renewable energy law have paved the way for the strong market growth of this technology within the last decade. Here the question arises as to when photovoltaics will reach a competitive level in Germany without the support of subsidies. The prominent grid parity approach is simple and considered critical in this discussion. It is critical because of the different references regarding the costs of electricity generated by a newly installed PV system and the electricity price of private households, which consists of electricity generation, distribution, sales as well as taxes and duties on the one hand. On the other hand, there are different time references in the calculation of electricity generation costs and electricity prices of private households. Transferring the approach of Levelized Costs of Electricity (LCOE) to all power generation plants within the energy mix means a redefinition of the grid parity of photovoltaics will be carried out. Here the electricity generation costs of photovoltaics as well as the energy mix will be calculated in the same way. The LCOE calculation refers to the whole life cycle of every power generation plant. That is why a balance between the high investment costs of photovoltaics and the increasing operation costs of fossil fuelled power plants is made. It can be shown that the reaching of competitiveness of photovoltaics in Germany depends on structural changes in electricity generation and it is to be realized within the anticipated time frame until the year 2020.     

Klimawandel: Wahrnehmung und Einschätzungen der deutschen Haushalte im Herbst 2012

This article presents results that are obtained from a survey among private households in Germany, which took place in the fall of 2012. A key result is that in comparison with a range of other global challenges, respondents are less concerned with fighting climate change, a remarkable outcome given that the share of climate change skeptics in the survey is likely to be lower than in the population owing to selfselection problems. This article addresses such self-selection problems, as well as other shortcomings of surveys, and provides for a discussion on how to cope with them.     

Versorgungsqualit?t in der leitungsgebundenen Gasversorgung

The incentive regulation ordinance (Anreizregulierungsverordnung (ARegV)) stipulates the implementation of a quality regulation scheme for the second regulatory period gas (2013?C2018). This raises the issue how to specify, define and stimulate quality specifically for gas transportation and distribution. According to §§18?C20 ARegV, the dimensions ??reliability?? and ??network capacity?? need to be incorporated. Due to the lack of tangibility of quality in the gas sector, the issue of quality turns out to be much more complex than in the electricity sector where quality or??more specifically??reliability is mainly associated with the premise ??keeping the lights on??. In order to establish a first idea of the current situation in the area of quality in grid-bound gas supply, WIK conducted expert interviews with different stakeholders from industry and science. Following this first step, a workshop took place to present the results from the survey and to further discuss the main issues. Overall, it turned out from the discussion that the definition and differentiation of the different quality dimensions is very complex due to the heterogeneous views of the stakeholders on priorities and incentives. Two different attitudes towards the regulation of the quality dimension reliability emerged in the interviews. One part of the group advocated the implementation of a corresponding q-element in the regulatory formula, whereas the other part preferred a quality monitoring without regulatory effects. Overall, the interviews and the workshop served its purpose in collecting the different opinions of the stakeholders. Based on these results, the discussion can be deepened. To approach the topic, it will be shown how the regulators in the Netherlands and Hungary converted the rarely practiced quality regulation into practice.     

Und Aktion! – Konzeptualisierung der Rolle individuellen Akteurshandelns in sozio-technischen Transitionen am Beispiel der regionalen Energiewende im bayerischen Allgäu

The German “Energiewende” is one of the most ambitious societal transition projects in recent times. It causes fundamental political and economic changes in the energy system in Germany and the whole of Europe. These great societal and technological changes of the current energy regime are of particular interest for research on sustainability transitions. In this research strand, however, the role of individual agency for socio-technical transitions is hardly considered. What drives actors who decisively pushed the regional energy transition? Which strategies and types of action do they choose to foster the transition? How do individual strategies and actions depend on the socio-technical system environment and how does the socio-technical system environment react to the individual actions? To analyse these questions, we apply the Human-Environment Systems (HES) Framework (Scholz, 2011) for the first time to socio-technical systems. Based on an exemplary analysis of the regional energy transition in the Allgäu region in Germany, we propose an adaptation of the HES Framework for socio-technical systems. Finally, we reflect on how the adapted HES framework for socio-technical systems can contribute to a better understanding of individual agency in systemic transitions.     

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.     

W?rmed?mmungs-Strategien im Haushaltssektor und ihr Beitrag zu Materialeffizienz und Emissionsminderung – eine Langfristanalyse bis zum Jahr 2050

An often controversial question is whether a massive insulation of houses in the overall balance does not cause more resource consumption and emissions than it saves in the end. To investigate this question, for the first time a trade-off analysis has been performed. For this, a bottom-up impact analysis model was developed, whose core forms an emissions- and energy model for the household sector which is coupled with a life cycle assessment tool. Both models provide the framework for energy scenarios to 2050, claiming for each decade refurbishment rates and energy mixes. Thus, ??pure?? energy scenarios can be extended by resource policy analyses and the effects of various insulation strategies might be determined. The central result of modeling is that additional costs are compensated for insulating (extruded polystyrene foam XPS and cellulose were examined) both resource- and emission-side in almost all environmental impact categories with significant savings in building heating. Essentially, there are no trade-offs identified, and the percentage contribution of the insulating materials on the environmental impact indicators is low. In contrast, the choice of foaming agent in the foamed XPS insulation is relevant: Compared with the XPS used in Germany, which is largely CO₂ foamed insulation, one which has a high proportion of HFCs, leads to a high trade-off regarding the impact category ??stratospheric ozone depletion?? and leads to a noticeable, but not significant effect on the global warming potential. A sensitivity analysis with the alternative cellulose insulation material shows that the already low shares of the insulation continue to decrease with regard to the environmental impact indicators. However, with regard to the material intensity, XPS and cellulose insulation are associated with similar effects. In summary, it can be stated that for both insulation materials ambitious strategies??with regard to all factors analysed in the study??can significantly contribute to material efficiency as well as to emissions reduction targets.     

„Bewertung von physischen Übertragungsrechten — Eine Analyse der Grenzkuppelstellen zwischen Deutschland und den Niederlanden“

The purpose of this paper is to discuss market-coherent valuation of physical transmission rights for cross-border capacities between Germany and the Netherlands. Aiming at a fair valuation of these contracts, the most important stylized facts of electricity prices such as mean reversion, spikes and correlations of regional prices have to be considered. We present two different approaches to the valuation of physical transmission rights and perform a quantitative analysis of the results. On the one hand various challenges of modeling regional price differences are discussed. On the other hand a structural undervaluation of required flexibility is indicated, which implicates missing incentives for the extension of cross border capacities.     

Monetäre Anreize zur Steuerung der Ladelast von Elektrofahrzeugen – eine modellgestützte Optimierung

Electric mobility is supposed to contribute to climate policy targets by reducing CO₂-emissions in the transportation sector. Increasing penetration rates of electric vehicles (EV) can lead to new challenges in the electricity sector, especially with regard to local distribution networks. Thus the management of charging loads is discussed as a key issue in energy economics. Due to their long parking times, high electricity and power demand, EV seem to be predestined for load management. Monetary incentives as dynamic pricing can be suitable for that: They reflect the current supply situation, pass the information to the consumers and can thus lead to a corresponding charging behaviour. In this article we analyse this interaction between dynamic pricing and charging loads. For this reason we have developed the optimization model DS-Opt+. It models a total number of 4,000 households in two residential areas of a major city with regard to its electricity demand, its mobility behaviour and its equipment of photovoltaic systems. Four different pricing models are tested for their effects on charging behaviour and thus the total load of the residential area. The results illustrate that only fairly high penetration rates of EV lead to remarkably higher electricity demand and require some load management. The tested dynamic pricing models are suitable for influencing charging loads; load-based tariffs are best in achieving a balanced load curve. In our analysis uncontrolled charging strategies are superior regarding a balanced load curve than controlled strategies by time-varying tariffs. Our results lead to several implications relevant for the energy industry and further research.     

Optimierte Integration der Elektromobilität in das Stromversorgungssystem bei hohen Anteilen erneuerbarer Energien

Electric mobility will play a key role for the transformation of the energy supply in Germany [the “Energiewende”]. A successful market development of plug-in hybrids and battery electric vehicles and a full fleet penetration in the long-term are the most efficient and effective measure for integrating large amounts of renewable energy into the transport sector and for reaching the efficiency targets. These new electricity consumers in the supply system will cause additional electricity loads strongly dependent on the mobility needs of the vehicle users. A controlled battery charging is able to avoid new peak demands and to increase the efficiency of the power generation system by using excess power. By scenario analysis, the German Aerospace Center (DLR) in cooperation with the Fraunhofer Institute for Solar Energy Systems (ISE) and the Institute for High Voltage Technology of the RWTH Aachen investigated a possible successful development path of electric mobility in Germany and its integration into and interaction with the future power supply system. From both perspectives—the one of the total supply system as well as the other of local distribution grids—the results show promising potentials but also limits.     

„Collaborative Governance“ – ein neues Konzept für die Regulierung der europäischen Strom- und Gasmärkte?

Current British and American publications about the liberalization of electricity and gas markets demand a paradigm shift in the regulation of energy networks. These publications can be subsumed under the scientific debate about “collaborative governance” in the USA. They call for an integration of network users and consumers into the regulatory process. Their philosophy resembles the philosophy of the negotiated third party access in Germany from 1998 till 2005. Their regulatory strategy might be more effective than the actual European “command and control” strategy in establishing competitive energy markets. This article examines and evaluates these publications and their regulatory strategy.     

Zahlungsbereitschaft für grünen Strom: Zunehmende Kluft zwischen Wunsch und Wirklichkeit

This paper presents evidence on preferences for green electricity, drawing on two stated-preference surveys conducted in 2013 and 2015 among 6000 households. It uncovers a strong contrast between the households – rising general acceptance of supporting renewable energy technologies and their shrinking individual willingness-to-pay for green electricity.     

Anforderungen an den konventionellen Kraftwerkspark – wieviel und welche Kraftwerkskapazit?t wird ben?tigt?

The electricity supply system will, particularly in Germany, significantly be determined by the use of renewable energy sources. A?decreasing energetic utilization along with an increasing flexibility demand lead to chancing requirements for the conventional plant fleet. The question arises to what extent conventional generation capacity is needed in the future and if??compared to today??additional technical requirements have to be fulfilled due to the increased flexibility demand. Furthermore it has to be discussed how a required capacity level can be achieved and if??and under which conditions??today??s market design is sufficient or if additional capacity mechanism are necessary. These questions are discussed in this article. The questions as to the required capacity level and the means to achieve it depend on the perspective, which is chosen with respect to security of supply. Choosing a European perspective, i.e. a common responsibility for an appropriate level of security of supply in Europe, additional capacity mechanism are not necessary. Choosing a national perspective, i.e. requiring that national demand can??theoretically??be covered by capacity available in the particular country, does not only significantly increase the necessary amount of generation capacity but also??due to the fact that the electricity market already today is organized on a European rather than a national basis??requires additional capacity mechanisms to cover capacity demand. With respect to the flexibility demand a concerted as well as coordinated acting of the different independent market players is necessary to cover a more volatile residual load. However, there is no additional demand for technical flexibility.     

Die Marktprämie im EEG 2012: Ein sinnvoller Beitrag zur Markt- und Systemintegration erneuerbarer Energien?

With the share of renewable energies within the electricty sector rising, improving their market integration (i.e. inclusion in the steering and remuneration processes of the electricity market) and system integration (i.e. enhanced responsibility for grid stability) is of increasing importance. To transform the energy system efficiently while ensuring security of supply, it is necessary to increase the alignment of renewable electricity production with short- and long-term market signals. The German Renewable Energy Sources Act 2012 introduced the market premium to provide market experience to renewable plant operators and incentives for demand-oriented electricity production. Shortly after its introduction, the instrument is already being criticised as ineffective and expensive. Building on early experiences, this article examines whether the market premium in its current design improves market and/or system integration, and if it seems suitable in principle to contribute to these aims (effectiveness). Also, potential efficiency gains and additional costs of “administering integration” are discussed (efficiency). While market integration in a strict sense (i.e. exposing renewables to price risks) is not the purpose of the market premium, it has successfully increased participation in direct marketing. However, windfall profits are high, and the benefits of gradually leading plant operators towards the market are questionable. Incentives for demand-oriented electricity production are established, but they prove insufficient particularly in the case of intermittent renewable energy sources. A continuation of the instrument in its current form therefore does not seem recommendable. To conclude, potential alternative solutions are presented.     

Beitrag von technologischen und strukturellen Veränderungen im Energiesystem der EU-27 zur Erreichung ambitionierter Klimaschutzziele

To stabilise the concentration of GHG (Greenhouse gases) in the atmosphere to a level of 450ppm (parts per million), a strong climate policy in the EU-27 will be required. The target is achievable through a 71% reduction of GHG emissions from 1990 emission levels by the year 2050. With the regionalised Pan-European TIMES energy system model, the role of technologies with regard to efficiency improvement, fuel switching and energy saving measures will be analysed under such an emission reduction target. The Pan-European TIMES model illustrates in detail the whole energy system of the different member states of the EU-27 plus Iceland, Norway and Switzerland. The limited resource and import potentials of different energy carriers, the competition of the use of energy carriers among different sectors and the country specific differences in energy demand will be taken into account. The results show that the energy consumption of the EU is influenced rather by political targets and positions related to climate protection, security of supply and the use of nuclear energy than by the available technological options. Under a climate protection scenario with restricted use of nuclear energy, the most commonly used options are to increase the use of renewable energy in all sectors, produce electricity in combination with carbon capture and storage (CCS) and to increase the use of electricity over other fuel sources in the demand sectors. Furthermore, technological improvements will be required throughout the entire energy system if political targets are to be successfully realised.     

Staat versus Markt: Konsumentenpräferenzen und die Förderung erneuerbarer Energien

This paper presents a set of artefacutal field experiments on individual preferences and willingness to pay, respectively, for the consumption of green electricity. Based on an economic model of individual preferences for the provision of public goods, the design of our experiments involved different scenarios: subjects had to decide about their individual spending on green electricity as well as about the level of public subsidies for green electricity. Unlike hypothetical empirical methods, the experiments involved an incentive mechanism, i.e. subjects had to face the monetary consequences of their decisions. Our empirical results are distinct from those of other studies. It seems that the market potential of green electricity is overestimated at present. Hence, the market will not release the public in financing subsidies in this field. The conclusion can be drawn that individuals prefer binding collective contributions rather than individual market-driven activities. However, we contradict the standard explanation of political economy that such a kind of preference for regulatory instruments may be motivated by cost-illusion. Subjects were willing to bear far higher taxes as compared to the price mark-up they were willing to pay for green electricity offered by the market.