Search

Abstract This paper provides insights from the extant literature on institutional entrepreneurship in emerging fields which could enable us to understand how the innovative idea of 'energy community' arose, became new practices, and has been institutionalized over time. In August 2008, the people of St. Peter, a Black Forest rural town in Germany, decided to build their own energy co-operative for the operation of the biomass District Heating Plant (DHP). The key driving forces for this comprised a wide range of sustainability-related discourses, such as climate protection, energy supply security, and regional economic development. The biomass DHP, as an environmentally-friendly heating system, has become a taken-for-granted practice and has been presented as an 'inspirational' example to other communities in the region. The main contribution of this study is to develop and use a multi-level analytical framework to elucidate the process of legitimation and sense-making of the notion of the energy community St. Peter. The key conclusions are that institutional entrepreneurs are dispersed across space, social status, sector, and governance levels; their agency is distributed among multiple levels of action and multiple stages of development; and they use a range of social skills to justify their action for institutional change. Therefore, community-based initiatives should draw on multiple discourses that address both individual interests (stable prices and supply security) and collective concerns (environmental protection). In this way, wide public support for transforming existing energy practices into more renewable ones can be achieved. Highlights • This paper provides insights from the literature on institutional entrepreneurship in emerging fields. • It develops and uses a multi-level framework to elucidate the process of legitimation and sense-making of energy practices. • The key findings are that the agency is distributed among multiple levels of action and multiple stages of development. • Energy communities draw on multiple discourses to address both individual and collective concerns of energy transition. [ABSTRACT FROM AUTHOR]

The liberalization of electricity markets and the development of renewable energy sources has led to new challenges for decision makers. These challenges are accompanied by an increasing uncertainty about future electricity price movements. The increasing amount of papers, which aim to model and predict electricity prices for a short period of time provided new opportunities for market participants. However, the electricity price literature seem to be very scarce on the issue of medium- to long-term price forecasting, which is mandatory for investment and political decisions. Our paper closes this gap by introducing a new approach to simulate electricity prices with hourly resolution for several months up to three years. Considering the uncertainty of future events we are able to provide probabilistic forecasts which are able to detect probabilities for price spikes even in the long-run. As market we decided to use the EPEX day-ahead electricity market for Germany and Austria. Our model extends the X-Model which mainly utilizes the sale and purchase curve for electricity day-ahead auctions. By applying our procedure we are able to give probabilities for the due to the EEG practical relevant event of six consecutive hours of negative prices. We find that using the supply and demand curve based model in the long-run yields realistic patterns for the time series of electricity prices and leads to promising results considering common error measures. [ABSTRACT FROM AUTHOR]

In view of the current geopolitical situation, the EU and its Member States are accelerating efforts to reduce their dependency on fossil fuel imports, while simultaneously tackling the climate crisis. With heating in buildings accounting for a large share of the energy consumption in the EU, policies to phase-out fossil fuels for heating and to switch to renewables are key elements. In the context of the proposed actions to phase-out fossil fuels at EU level, this article provides a systematic analysis of current and planned phase-out regulations for fossil fuel boilers in the EU Member States. The paper quantifies the share of energy consumption for heating that is addressed by such regulations and finds that the current regulations only address about 10% of the total fossil energy consumption for heating in the EU. The share increases to almost 30% when considering the planned regulations, reflecting the fact that large energy consumers such as Germany and the Netherlands have announced such regulations. The analysis shows that several Member States with high energy consumption for heating have neither implemented nor announced plans to introduce phase-out regulations for fossil fuel heating. The study concludes that immediate policy action is needed both at EU and at Member State levels. At EU level, the proposed introduction of an end-date for stand-alone fossil fuel boilers needs to be substantiated and implemented into the legislative framework. At the national level, phase-out regulations for fossil fuel boilers need to be expanded both in quantity and scope. [Display omitted] • Systematic analysis of phase-out regulations for fossil fuel boilers in the EU. • Only 10% of the EU fossil energy used for heating is covered by phase-out regulations. • Including planned regulations, the share of heating energy covered by phase-out regulations increases to almost 30%. • Comparison of different approaches for implementing regulations for phasing out fossil fuel boilers. [ABSTRACT FROM AUTHOR]

Bioenergy conversion technologies have been frequently described and analysed in the literature, but a comprehensive and detailed comparison between the complex individual characteristics of each technology is still lacking. Therefore, the paper contains a description of the technical, economic and environmental properties of each technology with a special focus on the German bioenergy sector. The study presents an analysis of different bioenergy applications with regard to their specifications, power/heat output range and their areas of application. Due to the fact, that biomass combustion applications are the most widespread and market proven renewable conversion technologies, a detailed analysis of decentralised, biomass-fired CHP plants is presented in the paper. The overview of the individual characteristics of different biomass conversion routes shows that biogas plants achieve high electrical efficiencies, are available with a broad range of capacities and belong to the established technologies. Although the investment costs of biogas plants are relatively high, biomass conversion with anaerobic digestion can be seen as one of the most promising option for a sustainable energy supply in Europe. [ABSTRACT FROM AUTHOR]

Abstract Despite a major, policy-driven increase in research on the food – energy – water (FEW) nexus in recent years, research addressing the required changes in policy structures and processes for an effective, integrated governance of FEW nexus resources is still in its infancy. This paper adapts the Institutional Analysis and Development Framework to the requirements and challenges of FEW nexus governance and sets a special focus on action situations, actors, and institutions. The analysis thus contributes to the debate about the practicality and benefits of a comprehensive FEW nexus policy approach. Two different conceptual FEW nexus frameworks are developed, which span the spectrum of possible integration options. The first one describes a holistic integration framework that defines the FEW nexus as a single, fully integrated system. The second one represents vertical policy integration and is largely based on existing structures and a reframing of the present institutional setting. After their theoretical derivation, the two hypothetical frameworks are analyzed with respect to their strengths and weaknesses in governing the FEW nexus using two sample cases of integrated FEW nexus governance in Germany. The results show that effective FEW nexus governance requires a combination of both integration options. Highlights • Two novel FEW nexus governance frameworks are developed. • The holistic FEW nexus framework represents horizontal policy integration. • The FEW nexus cooperation framework represents vertical policy integration. • In Germany, both frameworks are used in current policy measures. • Successful FEW nexus governance requires instruments from both frameworks. [ABSTRACT FROM AUTHOR]

Abstract As for other renewable energy sources in Germany like wind or photovoltaics, biogas has rapidly expanded in the past fifteen years. The installed electricity capacity for German biogas plants increased from 0.2 GW el in 2001 up to about 4.2 GW el by the end of the year 2016. This expansion has been supported in particular by the Renewable Energy Sources Act (EEG) through electricity Feed-In-Tariffs (FITs). However, major uncertainties are linked to the future capacity expansion in particular due to volatile electricity and energy crops prices. Taking into account this situation this paper analyzes possible future developments of the German biogas plant capacity up to 2030. For this purpose, a regional optimization model is employed, with the objective of determining the optimal economic development of the future biogas plants under different legal framework conditions. The base scenario with a constant energy crops cost evolution shows that the EEG 2012 framework -if maintained- would have fostered the development of agricultural plants, especially co-digestion plants valorizing energy crops and manure. The new EEG 2014 stops the expansion of energy crops mono-digestion plants, which will no longer be built due to an unprofitable situation. The German biogas market will thus face a paradigm shift and move towards the increase of biowaste and small-scale manure plants. Further scenarios quantify the impact of a strong variation of three main fundamental drivers, namely the energy crop costs, the EPEX-Peak electricity price and the biowaste valorization revenues, on future capacity developments. Based on the model results recommendations in direction of plant operators and policy-makers are formulated aiming at a more sustainable electricity production from biogas. Further work should consist in integrating the present analysis in national bioenergy models under the EEG 2017 legal framework. [ABSTRACT FROM AUTHOR]

Local authorities are key actors for implementing innovative energy efficiency technologies (retrofitting) to reduce end-use energy demand and consequently reduce negative effects of high energy use such as climate change and public budget deficits. This paper reports the results of a large-scale survey of German municipalities by assessing drivers and barriers for deploying LED street lighting as an example of innovative retrofits. The results indicate that competencies and capacities, transparency of the underlying technology base, and a clear proposition of savings are crucial drivers for municipal retrofitting engagement. Most significant barriers include lack of experience, the tendency to wait for future improvements of innovative energy efficiency technologies, and existing contracts with energy suppliers, manufacturers, or other conventional retrofitting contractors. Investments in municipal competency building (both regarding technologies and procurement) as well as diffusing standard tendering criteria and (public) monitoring of their effectiveness are highly recommended to accelerate the municipal modernization process. [ABSTRACT FROM AUTHOR]

Previous studies about the trends and sources of PV soft cost reduction have only offered a limited understanding of systemic aspects that drive this development. Drawing on concepts of sectoral innovation system theory, this study analyzes the evolution of the German PV sectoral system since the early 1990s, focusing specifically on key processes associated with the deployment of building-sited PV systems. The findings from the analysis suggest that soft cost reductions have been the result of numerous processes, including demand and market expansion, interactions across various agents, knowledge generation and learning, diversity creation and selection, and development of the institutional context. This paper offers a novel application of the sectoral innovation system concept in order to investigate incremental innovations and associated cost reductions that occur in the deployment of new energy technologies. For policymakers and other practitioners, the study offers new insights on how to support various processes that can enable (soft) cost reductions. [ABSTRACT FROM AUTHOR]

This paper provides answers to questions raised by Hirth and Ziegenhagen [1] regarding the “German paradox” in the balancing power markets. We show that in spite of the increasing energy production from variable renewable energy sources, there is no need for a higher demand of balancing power in Germany because adaptations in the energy market design were undertaken and Grid Control Cooperations led to immense efficiency savings. Additionally, we investigate the price developments in the German Secondary balancing power market. We find evidence that the suppliers coordinate on a price level which is (far) above the competitive level and that they orientate their power bids towards previous auction prices. [ABSTRACT FROM AUTHOR]

Abstract: Industry represents a very promising application area for solar thermal technology, since it accounts for 27% of the total final energy consumption in Germany and uses 74% of its energy consumption as thermal energy. In order to develop this application area, it is necessary to know which industrial sectors have the highest potential and which processes within these sectors are most suitable for the integration of solar heat. For this paper the industrial heat consumption in Germany was analyzed, which leads to the selection of the most promising sectors within industry. Furthermore, the quantitative potential for Germany in total and for 11 selected sectors, that were identified to be most promising for the use of solar heat, was calculated. These are Chemicals, Food and beverages, Motor vehicles, Paper, Fabricated metal, Machinery and equipment, Rubber and plastic, Electrical equipment, Textiles, Printing and Wood. These sectors are analyzed to identify suitable processes for the integration of solar heat. In total the theoretical potential of solar heat for industrial processes below 300°C in Germany accounts for 134TWh per year, the technical potential being 16TWh per year or 3.4% of the overall industrial heat demand. This is the highest share of the European potential of 72TWh per year. The results of this study facilitate the prioritized application of solar thermal energy in industrial sectors and processes for Germany and other countries. [Copyright &y& Elsevier]

This paper presents a comparative analysis of energy governance regarding nonconventional renewable energy sources (NCRES) in Brazil and Germany. Brazil is a world leader in the use of conventional renewable energy sources, such as hydro power, while Germany has been achieving outstanding results in fostering NCRES. The focus is on two critical issues: the legal and regulatory framework and the institutions created to support the NCRES market development. The comparison shows that, despite the very different energy situations and policy drivers, valuables lessons can be extracted from the German experience. The main lesson for Brazil is to think NCRES as a strategic opportunity to rely less on fossil fuel and large hydroelectric power plants, to decentralize the electric power sector, to use the huge solar, biomass and wind power potential available in the country and to create a environment-friendly NCRES industry. To this end, three critical points were identified: (1) the legal and regulatory framework should be improved; (2) long-term energy planning taking into account social, economic and climate issues and; (3) the current institutions supporting NCRES in Brazil should be upgraded and/or new ones, such as more specific energy agencies, should be created. [ABSTRACT FROM AUTHOR]

Abstract: The increase of the wind power penetration in the electrical grids of Denmark, Germany, Spain and other countries and regions is challenging the stability of the system. The subject of this paper is to review the main problems of the connection of wind farms to the grid and how the grid codes must be adapted in order to integrate wind power generation capacity without affecting the quality and stability of the grid. This paper also summarizes the grid codes that have already been modified to incorporate high levels of wind power. [Copyright &y& Elsevier]

In recent years, wind power has emerged as an important source of renewable energy. When onshore and offshore wind farm regions are connected to the grid for power generation, consistent multi-location short-term wind power predictions are extremely valuable in terms of assuring the power system's safety, sustainability, and economic operation. An abrupt variation in wind power generation influences the efficiency of the regional power grid. This makes accurate short-term forecasting essential for high-level planning and scheduling of power grids. To address the issue, this paper presents two variants of recurrent neural networks (RNN): gated recurrent unit (GRU) and long short-term memory (LSTM) models considering substantially better prediction accuracy to forecast a country-wide (Germany) wind power data for daily (t + 1), and multi-step (t + 3, t + 5 , and t + 12) hours ahead. In addition, wind velocities [m/s] measured at heights of 2, 10, and 50-m (above ground level) are exploited as an essential characteristic among the available input variables and evaluated each feature subset based on four training divisions (80-20%, 70-30%, 60-40%, and 50-50%) and compared the results with ARIMA and SVR approaches in the literature. The findings reveal that the RNN-GRU model not only can achieve higher predicting accuracy but also has a faster learning speed over long sequences. • Multivariate analysis of hourly wind power predictions is carried out. • The prediction model integrated RNN-GRU and RNN-LSTM. • A countrywide dataset for Germany in 2016 is employed for the forecast. • Accuracy and computational efficiency were used to evaluate the performance of proposed time series models. • Comparison with reported models and ablation strategies supports the design of individual modules in RNN-GRU. • RNN-GRU with multi-step/multi-location demonstrated potential for large-scale wind farm applications. [ABSTRACT FROM AUTHOR]

The current development of clean energy in Taiwan is in the embryonic stage. Even though in recent times Taiwan’s development of renewable energy has emphasized wind power and photovoltaic power, current statistics show they supply only a small portion of total national power needs, and that wind power and solar power are still in development. In order to promote the growth of clean energy, it is necessary to compare the support mechanisms of developing clean energy in different countries. The success of implementing clear energy in Germany is often followed by other countries, including Taiwan. Thus, this paper explores the German experience of implementing a Feed-in Tariff (hereafter FIT) and compared it with the FIT system in Taiwan to illustrate the differences and similarities between these countries. The results could be used as a reference for the future modification of the FIT system in Taiwan. [ABSTRACT FROM AUTHOR]

The long-term energy strategy issued by the German government in 2010 and 2011 embraces a substantial reduction of CO 2 emissions and high shares of renewable energy in electricity production, along with energy efficiency improvements and an accelerated nuclear phase-out. While several studies illustrate scenarios reaching these targets, there are substantial uncertainties pertaining to key assumptions, particularly long-term electricity demand and the large-scale availability of offshore wind and carbon capture and storage (CCS). This paper explores conditions under which model-based scenarios for the German electricity sector comply with the official targets for CO 2 emission reductions and renewable shares. We apply the energy system model LIMES-D, which allows for a joint optimization of generation and transmission capacities. The results indicate that reducing electricity demand plays a crucial role for attaining the government׳s targets. Scenarios for which either offshore wind or CCS is not available show an even stronger need for a decreasing electricity demand to reach the targets and a different pattern of transmission capacity expansion than is the case with full technology availability. Hence, a broad technology portfolio could in turn hedge against future power demand increases that may challenge the joint attainment of the German decarbonization and renewable energy targets. [ABSTRACT FROM AUTHOR]

The increasing utilization of renewable energy sources (RES) is a major energy policy strategy in many countries worldwide. Germany is a forerunner in the deployment of RES and has ambitious goals for the future. The support and use of renewables affects the economy: It creates business opportunities in sectors producing renewable energy facilities, but comes with costs related to supporting its deployment. This paper analyses and quantifies the net balance of economic effects associated with renewable energy deployment in Germany until 2030. To this end, we use a novel model, the ‘Sectoral Energy-Economic Econometric Model’. This is an econometric multi-country model which, for Germany, contains a detailed representation of industries, including 14 renewable energy technology sectors. Our results show that renewable energy expansion can be achieved without compromising growth or employment. The analysis reveals a positive net effect on economic growth in Germany. Net employment effects are small, but also positive. Their size depends strongly on labour market conditions and policies. Results at the industry level indicate the size and direction of the need for restructuring across the sectors of the Germany economy. [ABSTRACT FROM AUTHOR]

The future market diffusion of alternative fuels in the passenger car sector is of great interest to both carmakers and policymakers in order to decrease CO 2 emissions. The decision to buy a car is not totally objective and only partly based on cost. For this reason, those modeling the future market evolution of cars powered by alternative fuels try to include behavioral and non-cost related aspects. This paper analyzes the integration of user behavior into market diffusion models and compares three models that include this aspect. The comparison comprises three parts: first, it compares the modeling approaches, then uses a harmonized data set to model the future market diffusion of alternative fuel vehicles, with and without behavioral aspects. The most important aspects of user behavior included in the models are the use of charging infrastructure, the limited model availability, the consideration of range anxiety as a hampering factor or the willingness-to-pay-more for alternative drivetrains as a supporting factor, as well as a distinction of users' driving distances. User behavior is considered in various ways, but always has a limiting effect on electric vehicle market diffusion. While a model that distinguishes individual users and driving distances stresses the high relevance of this aspect, it is considered less important in models with a more aggregated inclusion of user behavior based on logit functions. • Integrating user behavior into models reduces sales of alternative fuel vehicles. • High market shares of electric vehicles in 2030 (up to 50%) nonetheless. • User behavior important, but policies, energy prices and purchase prices also matter. • Individual effects of user behavior can be better analyzed in disaggregated models. • Aggregated models are less sensitive to changes in user behavior. [ABSTRACT FROM AUTHOR]

The future market diffusion of alternative fuels in the passenger car sector is of great interest to both carmakers and policymakers in order to decrease CO 2 emissions. The decision to buy a car is not totally objective and only partly based on cost. For this reason, those modeling the future market evolution of cars powered by alternative fuels try to include behavioral and non-cost related aspects. This paper analyzes the integration of user behavior into market diffusion models and compares three models that include this aspect. The comparison comprises three parts: first, it compares the modeling approaches, then uses a harmonized data set to model the future market diffusion of alternative fuel vehicles, with and without behavioral aspects. The most important aspects of user behavior included in the models are the use of charging infrastructure, the limited model availability, the consideration of range anxiety as a hampering factor or the willingness-to-pay-more for alternative drivetrains as a supporting factor, as well as a distinction of users' driving distances. User behavior is considered in various ways, but always has a limiting effect on electric vehicle market diffusion. While a model that distinguishes individual users and driving distances stresses the high relevance of this aspect, it is considered less important in models with a more aggregated inclusion of user behavior based on logit functions. • Integrating user behavior into models reduces sales of alternative fuel vehicles. • High market shares of electric vehicles in 2030 (up to 50%) nonetheless. • User behavior important, but policies, energy prices and purchase prices also matter. • Individual effects of user behavior can be better analyzed in disaggregated models. • Aggregated models are less sensitive to changes in user behavior. [ABSTRACT FROM AUTHOR]

The interest in low-carbon hydrogen technologies is growing fast in politics and the economy. The ramp-up of a hydrogen market is a critical phase, which requires the engagement and coordination of many heterogeneous stakeholders. A better understanding of who these stakeholders are and what relationships, chances, and risks they perceive is crucial to guide a hydrogen market ramp-up. This paper conducts a stakeholder analysis for Germany with a focus on the market ramp-up period. Interviews with 36 hydrogen experts, literature, and stakeholders from 78 real-world hydrogen research and demonstration projects are analysed with qualitative content analysis and social network analysis. In total, 49 stakeholder groups are identified and defined accordingly. The results indicate that established stakeholders' roles will significantly change in a future hydrogen market. Risks range from economic and supply chain risks to impacts on international policy. Chances are found along economic, ecological, and political dimensions. Political intervention during the market ramp-up should mostly focus on the economic gap between low-carbon hydrogen and fossil alternatives and on prioritising the allocation of scarce hydrogen supply on heterogeneous demand. Simultaneously, a long-term strategy should be envisaged to guarantee a competitive and non-discriminatory hydrogen market in the future. • Review of real-world hydrogen projects, literature, and expert interviews. • Identification of 49 stakeholder categories. • Analysis of chances, risks, and potential conflicts. • Electricity utilities are found to be a central player on the supply side. • Discussion of implications for the market ramp-up. [ABSTRACT FROM AUTHOR]

Abstract: The share of renewables in the primary energy demand of Germany has increased from 1.3% in 1990 to 11.7% in 2013. The plans are to increase it further, by the year 2050, to 50% or even 100%, by carrying out the national Energiewende (energy change/switch) programme. In this paper we analyze the current energy scenario and recall goals of the Energiewende programme. We also identify infrastructural and technological bottlenecks which are likely to affect the programme execution. By doing so, the enormous scale of this national venture becomes apparent and it is clear that its execution will last for several generations and perhaps even for a century or two. Additionally, we introduce an idea of Exclusively Green Energy Communities (EGECs) as an Energiewende mile-stone. Due to the dimensions of the tasks, the energy change/switch programme will last for several generations and perhaps even for a century or two. Realization of this overwhelming national venture has to proceed through milestones and demonstration projects. We propose demo-projects, called Green Energy Communities (GECs), to examine with what efforts and under what constraints such communities can operate using exclusively renewable forms of energy. [Copyright &y& Elsevier]

Abstract: Energy is essential for our preservation and the improvement of our life-style. Today all major production of energy is generated from fossil fuels, which are non-renewable and significantly pollute the environment. Access to clean and reliable energy is crucial for assuring the development of countries such as Mexico. Mexico's economy is based on producing energy from fossil fuels 1 [1] 91% of Mexico's energy is produced from non-renewable energy sources. Moreover, 36% of primarily renewable energy corresponds to the use of firewood for cooking used in a non-healthy and non-sustainable way [42]. GTZ is the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH (German Technical Cooperation, German Federal Ministry for Economic Cooperation and Development). and the change to sustainable ways of life is still uncertain. It becomes essential to look at developed countries where the transition to sustainability has been rapidly increasing. This paper gives an overview of energy policies and the potential of solar photovoltaic energy in two countries: Germany, a world leader in the generation and development of photovoltaic technology; and Mexico, a country with great solar photovoltaic potential. It also describes the characteristics, advantages and disadvantages of photovoltaic technology, including BIPV systems. [Copyright &y& Elsevier]

Abstract: A clear consensus exists in the German society that renewable energies have to play a dominant role in the future German energy supply system. However, many questions are still under discussion; for instance the relevance of the different technologies such as photovoltaic systems and wind energy converters installed offshore in the North Sea and the Baltic Sea. Also concerns exist about the cost of a future energy system mainly based on renewable energies. In order to be able to address the raised issues on a scientifically sound basis we have set up a new simulation model REMod-D (Renewable Energy Model-Deutschland) that models the energy balance of the electricity and heat sector including all renewable energy converters, storage components and loads for a future German energy system for a whole year based on an hourly energy balance. The target energy systems modeled use a high fraction up to 100% of renewable energies to cover the electricity and heat demand (heating and hot water). The model includes also energy retrofit of buildings as a measure to reduce future heat loads of the building sector. A mathematical–numerical optimizer is applied in order to identify system configurations with minimal overall annual cost. In this first part of a two-paper series we describe the methodology of the REMod-D model and discuss cost and performance values of all included components and in the second part we will discuss the results. [Copyright &y& Elsevier]

Previous studies have noted that, unexpectedly, Germany's dramatic expansion of wind and solar energy coincided with a reduction of short-term balancing reserves. This observation has been dubbed the "German Balancing Paradox". This paper provides further and updated evidence: since 2011, wind and solar energy have nearly doubled while both reserve requirements and reserve use have declined by 50%. The paper quantitatively explores one reason for reduced balancing needs: increased and improved short-term wholesale electricity trading on the intraday market. Trading is now commonly done around the clock and based on quarter-hour, rather than full-hour, contracts. The shift to quarter-hourly products alone explains a decrease in balancing energy by 17%. There is also strong evidence that market parties respond efficiently to imbalance charges, suggesting that incentive-based approaches to electricity balancing work. • Since 2011 wind and solar energy nearly doubled; balancing energy decreased by 50%. • One reason for this is the expansion of short-term electricity trading. • It is now common to trade electricity around the clock, and on a 15-min basis. • In general, the paper finds support for efficient short-term electricity markets. • Good market design allows integrating large volumes of renewable energy at low cost. [ABSTRACT FROM AUTHOR]

The transparency and open availability of energy system models and their input data are of particular importance due to their increasing complexity and policy relevance. In recent years, a large number of model-based scenario analyses have been carried out. These analyses are based on diverse model approaches and lead to a rather broad range of results, which due to different data structures and mathematical approaches are hardly directly comparable. In this paper, detailed and harmonized scenario input parameters are the basis of a systematic model experiment including four electricity system models. In the following, the different model approaches are classified and their respective results are discussed transparently. Consequently, differences in results can be interlinked directly with model properties. The results are compared focusing on a selection of output parameters, such as investment and dispatch decisions in flexible power plants, storage dispatch, wholesale electricity prices, CO 2 emissions and generation adequacy in hours with critical supply situations in Germany until 2030. Differences in the results are traced back to conceptual differences as the models can be distinguished not only with regard to their mathematical approaches, but also to their level of detail. Results indicate that next to the differences of the mathematical approaches (i.e., linear optimization vs. agent-based simulation), the myopic foresight perspective (e.g., rolling planning algorithm with 24- and 36-hours loops vs. perfect foresight in a closed loop for one year) are decisive for the range of obtained results. • Systematic comparison of four electricity system models. • Analysis of differences in model results for a future German power system. • Foresight perspective and mathematical approach influence model outcomes. • Investments of at least 2.6 GW seem profitable in Germany in 2030. • Need for 12 GW of additional flexibility to ensure generation adequacy in 2030. [ABSTRACT FROM AUTHOR]

Meeting the energy goals of the European Union requires new ways of managing energy. Decentralized energy management, cross-commodity energy production and usage optimization are promising means. Future neighbourhoods will include multiple forms of energy such as electricity, heat, and cooling. According to our vision, the smart neighbourhoods, can optimize energy across different vectors by sharing resources in a controlled way. The first contribution of this paper is a comprehensive review on market, regulatory and technological status to support the transition towards distributed cross-commodity energy management with focus on Germany and Finland. Markets disruption could lead to more decentralized structures. Mechanisms therefore have been proposed, but mostly without sector integration. Clean Energy Package includes legislation that is supportive towards cross-commodity energy sharing solutions. Corresponding implementation in Germany and Finland may be successful in both countries even though it differs. Regarding technology, the article identifies required technical components (IoT, AI and blockchain) focusing on their support decentralized and cross-sector energy systems. Key components of IoT are wireless communication and interoperability middleware. AI provides key technologies for modelling and optimization of sector-integrated and distributed energy systems. Even if there has been lots of research, practical implementations are still lacking. Furthermore, many technical challenges still exist for blockchain based solutions in decentralized energy systems. Moreover, organizational, and legal responsibilities need to be clarified to support the adoption of blockchains in decentralized energy systems. Finally, the article gives recommendations regarding an increasing implementation of cross-commodity sharing and how it can contribute to the energy transition. • Giving an overview of cross-commodity energy sharing in Finland and Germany. • It is shown how recent energy market development support energy transition. • Comparing the regulatory framework for smart components in energy markets. • Combination of IoT, AI and Blockchain to enable decentralized energy markets. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews on-farm renewable energy (RE) production and the associated feed-in tariff (FIT) policies in Germany, USA, Canada, Denmark and the Netherlands and the impact these policies have on Renewable energy implementation with particular focus on agricultural lands. A recent FIT policy implemented in Nova Scotia is examined and used as a case study to assess the potential affect these policies might be expected to have on RE implementation within the province. Several scenarios are developed based on the existing policy structure to provide a critical review of the policy and to identify potential modifications that might provide an increase in the implementation of RE. [Copyright &y& Elsevier]

Abstract: Grass is an excellent energy crop; it may be classified as a high yielding, low energy input, perennial crop. Over 90% of Irish agricultural land is under grass; thus farmers are familiar with, and comfortable with, this crop as opposed to a “new energy crop” such as Miscanthus. Of issue therefore is not the crop, but the methodology of generating energy from the crop. Numerous farmers across Europe (in particular Germany and Austria) use grass silage as a feedstock for biogas production; in a number of cases the produced biogas is scrubbed to biomethane and used as a transport fuel or injected into the natural gas grid. Many Irish farmers are considering converting from conventional farming such as beef production to grass biomethane production. Numerous technologies and combinations of such technologies are available; from one-stage batch dry systems to two-stage wet continuous systems; from one-stage continuous wet systems to two-stage systems incorporating a batch dry reactor coupled with a second stage high-rate reactor. This paper reviews work carried out both in the scientific literature and in practice at commercial scale. [Copyright &y& Elsevier]

Abstract: Renewable energy sources derived principally from solar energy have been gaining ground over the last few years and are now beginning to contribute to the global energy mix. Solar energy in the form of direct electricity conversion (photovoltaics) is already very popular in countries such as the United States, Germany and Japan. The enormous potential of photovoltaic (PV) technology is also obvious and favourable in countries with high irradiation such as the Mediterranean region. The objective of this paper is to review the different up and coming PV technologies, to explore the potential of different PV systems in countries with high solar irradiation and to compare their performance through the assessment of thirteen different types of PV systems that have been installed side by side in Nicosia, Cyprus and Stuttgart, Germany. Finally useful insight into the performance of the PV systems as a function of the meteorological conditions and location will be highlighted. [Copyright &y& Elsevier]

The European power system will have to change significantly in next decades to meet the ambitious targets set by the upcoming European Climate Law. In particular, intermittent renewable energy will be increasingly injected in the system creating potential stability problems. Already in the last five years it has become evident that if the grid expansion does not keep pace with increasing demand for transmission capacity, congestion will happen more and more often in the European power network. To handle congestion, Transmission System Operators extensively use redispatching, requiring individual plants to alter their market-based functioning pattern in order to cope with technical limitations of the network. While the cost of redispatching actions is well known, the change in emission patterns of both greenhouse gases and air pollutants caused by these actions is not, mostly because of a lack of detailed publicly available data. This paper covers such a gap taking Germany as a case study, thanks to the quality of the available data. Following the standard methodology for estimating the direct emissions from fossil fuelled and renewable fed power plants, the study estimates the changes in the emissions of four regulated air pollutants (namely NO x , SO 2 , Particulate Matter and CO) together with those of CO 2 related to redispatching, for the years 2015–2019. The case study of Germany shows how the management of congestions through redispatching does not necessarily imply an increase in the emissions associated with power production in a country, although it has not been possible to complete the study with a full picture of the consequences for other countries emissions because of lack of consistent data. • Power redispatching in Germany in 2015–2019 did not increase GHG and air pollutants emissions. • The impact of redispatching on emissions from neighbouring countries has not been assessed because of lack of data. • Curtailment of wind and solar power is increasing: Opportunities for further potential emissions reductions are lost. • Congestion in the power network remains an issue in Europe. [ABSTRACT FROM AUTHOR]

While it is generally accepted that our fossil fuel-dominated energy systems must undergo a sustainable transition, researchers have often neglected the potential impacts of this on water and land systems. However, if unintended environmental impacts from this process are to be avoided, understanding its implications for land use and water demand is of crucial importance. Moreover, developed countries may induce environmental stress beyond their own borders, for instance through extensive imports of bioenergy. In this paper, Germany serves as an example of a developed country with ambitious energy transformation targets. Results show that in particular, the politically-driven aspiration for more organic farming in Germany results in a higher import quota of biomass, especially biofuels. These imports translate into land demand, which will exceed the area available in Germany for bioenergy by a factor of 3–6.5 by 2050. As this will likely bring about land stress in the respective exporting countries, this effect of the German energy transformation ought to be limited as much as possible. In contrast, domestic water demand for the German energy system is expected to decrease by over 80% through 2050 due to declining numbers of fossil-fuelled power plants. However, possible future irrigation needs for bioenergy may reduce or even counterbalance this decreasing effect. In addition, energy policy targets specific to the transport sector show a high sensitivity to biomass imports. In particular, the sector-specific target for greenhouse gas reductions will seemingly promote biomass imports, leading to the above-described challenges in the pursuit of sustainability. • Implication of the German energy transition for land use and water demand analysed. • Potential stress in land use beyond Germany due to biomass imports analysed. • More organic farming in Germany can result in higher biomass imports. • Land for biomass imports exceeds Germany's available land by 3–6.5x by 2050. • Declining fossil power generation leads to lower water stress in Germany by 2050. [ABSTRACT FROM AUTHOR]

Abstract: In Taiwan, having implemented some incentive measures and subsidies, some progress of renewable energy in Taiwan has occurred; however, comparing the medium and long-term target reveals a wide gap. This paper (taking the solar photovoltaic (PV) for example), applies the ‘technological system’ framework to analyze the evolution of PV in Taiwan. Here, a comparative analysis is made of the development of PV between Germany and Taiwan to understand what issues that policy makers should focus on PV utilization in Taiwan. [Copyright &y& Elsevier]

Natural gas plays an essential role in Germany's energy system, both in the heating and electricity sectors. In order to achieve climate goals, numerous technologies aim at substituting fossil with renewable gas. Those technologies start reaching technical maturity, yet they are mostly not economically competitive under the current market conditions. To find transition paths to resolve this issue this paper introduces the simulation-based optimisation model MIREG (Model for the Integration of Renewable Gases). Combining a system-dynamic simulation of the various renewable gas options with an optimisation model of the gas market, the model puts strong focus on the reproduction of gas market's mechanisms and the implications of a rising penetration of renewable gases. The model is then applied to analyse the effects of different developments of market conditions and funding strategies on the possible share of renewable gases in the German gas mix until 2050. Results show that if renewable gases are supposed to account for a significant share of gas consumed in Germany they either need to be funded substantially or market conditions have to change. For a share of 23% renewable gas in the gas mix CO 2 prices for example would have to reach a level of 150 €/t CO2 by 2050 (300 €/t CO2 for 54%). The scenarios also indicate that in order to meet significant amounts of the German gas consumption with renewable gases, international solutions need to be aimed at e.g. by importing renewable gas from locations with high potential of renewable energy or by importing biomass. • Literature review on models investigating the future role of renewable gases. • Innovative approach for gas market modelling with high shares of renewable energies. • Scenario-based analysis of different funding strategies to promote renewable gases. • CO 2 prices found to be the most effective funding strategy. [ABSTRACT FROM AUTHOR]

The EU27 countries exert significant influence on the global patterns of the CO 2 -Emissions-Water-Energy (CWE) nexus. However, whether the associated benefits are similar for all countries is unclear. In this paper, an EU27 multiregional input-output model, at a sector level to identify the inter-regional and -sectoral CWE flows, and clarify the regional, sectoral and worldwide patterns of EU27 CWE network is presented. The results revealed an environmental inequality across the EU27 and impacts on the rest of the world. The EU27 countries contributed 1.4 Gt less CO 2 emissions, 64.5 Gm3 less water utilisation and 49 EJ less energy consumption, compared to the rest of the world while generating the equivalent economic output in 2014. This has dramatic effects upon the global environment. Germany, France and Italy are the biggest beneficiaries in the CWE nexus in the EU27. It is recommended that the EU27 provide more technical support to upstream countries in the EU and elsewhere to strive to improve their resource utilisation efficiencies. • The critical Carbon-Water-Energy (CWE) flows across the EU27 are analysed. • The regional, sectoral and worldwide patterns of EU27 CWE network are clarified. • An environmental inequality across the EU27 and impacts on the rest of the world. • Germany, France and Italy are the biggest beneficiaries in the CWE network of EU27. [ABSTRACT FROM AUTHOR]

Hydrogen can be transported over long distances when stored in Liquid Organic Hydrogen Carriers (LOHC). This transport is possible under the following conversion steps: first, hydrogen is stored inside a LOHC molecule (exothermic hydrogenation) at the starting point of the provision chain. Then, the loaded LOHC can be stored and transported. At the point of consumption, hydrogen is released (endothermic de-hydrogenation) and the unloaded LOHC returns to the point of hydrogen production. The optimal LOHC for transport should be liquid at ambient conditions and show similar properties to crude oil-based liquids (e.g., diesel, gasoline). This allows for a stepwise implementation using the existing crude oil-based infrastructure. However, there is a large variety of different LOHCs and other competing transport options; e.g., the transport of compressed hydrogen gas in pipelines or the transport of liquefied hydrogen in tanker ships. Against this background, this paper investigates the energy consumption and costs of these different hydrogen transport options. Therefore, the production of hydrogen is considered in areas with favorable renewable energy sources, followed by international transport logistics, and a local distribution in Germany. The assessment shows that the distance and the way heat is supplied to de-hydrogenate the LOHCs - especially for methanol - define the cost performance compared to a transport of compressed or liquid hydrogen. If the heat needed for dehydrogenation is covered by waste heat, dibenzyltoluene (DBT) or toluene can show benefits in terms of efficiency and costs. Furthermore, the different transport systems have different specific niches in which they are competitive; i.e., no specific transportation chain is superior to all systems under all circumstances. Nevertheless, the assessment shows that long-distance transport favors LOHC, while short-distance transport via pipelines can be used for lower costs. • Assessment of four Liquid Organic Hydrogen Carriers (LOHC) in different transport scenarios. • Comparison to compressed and liquefied hydrogen transport systems. • Comparison to electrical transmission. • Assessment of transport options in terms of economic and technical criteria. [ABSTRACT FROM AUTHOR]