Suchergebnisse

Coupling energy sectors within the emerging residential PV prosumer systems is necessary for an optimised use of the houseowners' own produced electricity. But the pure availability of different energy technologies in the system is not enough. By optimising the electricity usage as well as the capacities of PV generators, storage technologies, heat pumps and battery electric vehicles, not only the best solution in a technical point of view can be achieved, the need of finding the most financially beneficial system composition for single-family houses and tenements is possible. The study provides a detailed model for average German single-family houses and tenements and results for the energy transition period until 2050 for the optimised energy systems regarding optimised PV and stationary battery capacities and different heat storage capacities. Most noticeable outcomes can be observed by using a vehicle-to-home car, where a car can mostly take over the tasks of a stationary battery and by introducing a solidarity model using this type of car in tenement systems.

Two transition pathways towards a 100% renewable energy (RE) power sector by 2050 are simulated for Europe using the LUT Energy System Transition model. The first is a Regions scenario, whereby regions are modelled independently, and the second is an Area scenario, which has transmission interconnections between regions. Modelling is performed in hourly resolution for 5-year time intervals, from 2015 to 2050, and considers current capacities and ages of power plants, as well as projected increases in future electricity demands. Results of the optimisation suggest that the levelised cost of electricity could fall from the current 69 €/MWh to 56 €/MWh in the Regions scenario and 51 €/MWh in the Area scenario through the adoption of low cost, flexible RE generation and energy storage. Further savings can result from increasing transmission interconnections by a factor of approximately four. This suggests that there is merit in further development of a European Energy Union, one that provides clear governance at a European level, but allows for development that is appropriate for regional contexts. This is the essence of a SuperSmart approach. A 100% RE energy system for Europe is economically competitive, technologically feasible, and consistent with targets of the Paris Agreement.

This article aims at the creation of a holistic and analytic function for describing the transmission and distribution (T&D) grid power loss for all countries globally based on economical, geographical, political and technical available data. The created function is the very first of its kind, it is statistically well validated, and several examples are discussed. The function based on empirical data describes the dependence of the T&D grid power loss level on widely available metrics, such as GDP per capita, corruption perception index, area of the country, temperature, grid organization parameter and level of urbanization. The same function can also be used by modellers to anticipate the development of the T&D grid power loss in the years and decades to come. The suggested methodology could be easily reproduced and tuned to precise environmental conditions, what can be helpful for research in countries without available data. ; Post-print / Final draft

This study analyses energy transition pathways for the case of Bangladesh. The LUT Energy System Transition model, a high temporal - spatial resolution linear optimisation tool, is used to model an energy system transition from 2015 to 2050 for the case of Bangladesh. Four scenarios aimed at analysing different energy policies were created in order to replicate the present and alternative renewable energy based policies, with and without greenhouse gas emissions costs. The results show that emissions costs accelerate the transition towards a fully renewable energy system, however, removing these costs does not significantly affect the energy system, as renewables would still contribute 94% of the electricity generation by 2050. The Current Policy Scenario increases electricity and greenhouse gas emissions costs significantly especially, starting in 2025. The results indicate that countries like Bangladesh are prone to serious and complicated national risks that lead to several vulnerabilities like high electricity costs, increase in greenhouse gas emissions, energy insecurity and poor political trust, if present energy policies are pursued. However, focusing on indigenous renewable resources could help mitigate this vulnerability and bring about socioeconomic benefits. ; Post-print / Final draft

Transition to a cost effective and fossil carbon-free energy system is imminent for South Africa, so is the mitigation of issues associated with the 'water-energy nexus' and their consequent impacts on the climate. The country's key fossil carbon mitigation option lies in the energy sector, especially in shifting away from the coal-dependent power system. Pathways towards a fully decarbonised and least cost electricity system are investigated for South Africa. The energy transition is simulated for five scenarios, assessing the impact of various factors such as sector coupling, with and without greenhouse gas (GHG) emission costs. South Africa's energy transition is simulated using an hourly resolved model until 2050. This modelling approach synthesises and reflects in-depth insights of how the demand from the power sector can be met. The optimisation for each 5-year time period is carried out based on assumed costs and technological status until 2050. The modelling outcomes reveal that solar PV and wind energy, supplying about 71% and 28% of the demand respectively in the Best Policy Scenario for 2050, can overcome coal dependency of the power sector. The levelised cost of electricity increases just slightly from 49.2 €/MWh in 2015 to 50.8 €/MWh in the Best Policy Scenario, whereas it increases significantly to 104.9 €/MWh in the Current Policy Scenario by 2050. Further, without considering GHG emissions costs, the cost of electricity slightly increases from 44.1 €/MWh in 2015 to 47.1 €/MWh in the Best Policy Scenario and increases up to 62.8 €/MWh in the Current Policy Scenario by 2050. The cost of electricity is 25% lower in the Best Policy Scenario than in the Current Policy Scenario without factoring in GHG emissions costs and further declined to 50% with GHG emissions costs. The Best Policy Scenario without GHG emissions costs led to 96% renewables and the remaining 4% is supplied by coal and gas turbines, indicating pure market economics. The results indicate that a 100% renewable energy system is the least-cost, least-water intensive, least-GHG-emitting and most job-rich option for the South African energy system in the mid-term future. No new coal and nuclear power plants are installed in the least-cost pathway, and existing fossil fuel capacities are phased out based on their technical lifetime. ; Post-print / Final draft

Green hydrogen will be an essential part of the future 100% sustainable energy and industry system. Up to one-third of the required solar and wind electricity would eventually be used for water electrolysis to produce hydrogen, increasing the cumulative electrolyzer capacity to about 17 TWel by 2050. The key method applied in this research is a learning curve approach for the key technologies, i.e., solar photovoltaics (PV) and water electrolyzers, and levelized cost of hydrogen (LCOH). Sensitivities for the hydrogen demand and various input parameters are considered. Electrolyzer capital expenditure (CAPEX) for a large utility-scale system is expected to decrease from the current 400 €/kWel to 240 €/kWel by 2030 and to 80 €/kWel by 2050. With the continuing solar PV cost decrease, this will lead to an LCOH decrease from the current 31–81 €/MWhH2,LHV (1.0–2.7 €/kgH2) to 20–54 €/MWhH2,LHV (0.7–1.8 €/kgH2) by 2030 and 10–27 €/MWhH2,LHV (0.3–0.9 €/kgH2) by 2050, depending on the location. The share of PV electricity cost in the LCOH will increase from the current 63% to 74% by 2050. ; This study was made under the framework of the European Technology and Innovation Platform for Photovoltaics (ETIP PV). Open access of this study has been supported by the ETIP PV Secretariat which works in the framework of the ETIP PV-SEC II project. The project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 825669. A.J.-W. works at the European Commission – Joint Research Centre (JRC), Ispra, Italy. The views expressed are purely those of the author and may not in any circumstances be regarded as stating an official position of the European Commission.

The threat of climate change and other risks for ecosystems and human health require a transition of the energy system from fossil fuels towards renewable energies and higher efficiency. The European geographical periphery, and specifically Southern Europe, has considerable potential for renewable energies. At the same time it is also stricken by high levels of public debt and unemployment, and struggles with austerity policies as consequences of the Eurozone crisis. Modelling studies find a broad optimum when searching for a cost-optimal deployment of renewable energy installations. This allows for the consideration of additional policy objectives. Simultaneously, economists argue for an increase in public expenditure to compensate for the slump in private investments and to provide economic stimulus. This paper combines these two perspectives. We assess the potential for renewable energies in the European periphery, and highlight relevant costs and barriers for a large-scale transition to a renewable energy system. We find that a European energy transition with a high-level of renewable energy installations in the periphery could act as an economic stimulus, decrease trade deficits, and possibly have positive employment effects. Our analysis also suggests that country- specific conditions and policy frameworks require member state policies to play a leading role in fostering an energy transition. This notwithstanding, a stronger European-wide coordination of regulatory frameworks and supportive funding schemes would leverage country-specific action. Renewed solidarity could be the most valuable outcome of a commonly designed and implemented European energy transition.

Publiziert als Diskussionsbeiträge der Scientists for Future 10, 1–17, doi:10.5281/zenodo.6363715. Die Erstveröffentlichung erfolgte 2022-03-17. GERMAN SUMMARY (ENGLISH ABSTRACT: below): Aktuell importiert Deutschland 500 TWh/a Erdgas aus der Russischen Föderation. Der Großteil dieses Gases wird zur Erzeugung von Prozess- und Raumwärme eingesetzt. Durch eine beschleunigte Umstellung der Wärmeversorgung auf von erneuerbarem Strom angetriebene Wärmepumpen, regenerative Wärme in Wärmenetzen und die Substitution von Erdgas in der Stromerzeugung durch erneuerbare Energie sowie Energieeinsparung kann in wenigen Jahren so viel Erdgas eingespart werden, wie heute aus der Russischen Föderation importiert wird. Dazu bedarf es einer stark beschleunigten Verbreitung von Wärmenetzen und Wärmepumpen in Verbindung mit einer Ausbildungsoffensive im Handwerk. Auch Änderungen des regulativen Rahmens in Form eines Verbots von Öl- und Gasheizungen sowie finanzielle Anreize und gezielte Förderprogramme sind erforderlich. Mit solchen gezielten Anstrengungen kann Deutschland gleichzeitig einen deutlichen Beitrag im Kampf gegen die Klimakrise leisten. Schlagwörter: Klimakrise, Klimaschutz, Klimapolitik, Energiepolitik, Sicherheitspolitik, Deutschland, Energiewende, Energieautarkie, Russland, Ukraine, Erdgas, Wärmewende, Wärmepumpen ENGLISH ABSTRACT: Germany currently imports 500 TWh/a of natural gas from the Russian Federation. Most of this gas is used to generate process and space heat. By accelerating the conversion of heat supply to heat pumps powered by renewable electricity, renewable heat in district heating networks, and the substitution of natural gas in electricity generation with renewable energy, as well as energy conservation, as much natural gas can be saved in a few years as is currently imported from the Russian Federation. This requires greatly accelerating the spread of district heating networks and heat pumps in conjunction with a training offensive in the skilled trades. Changes to the regulatory framework in the ...

Publiziert als Diskussionsbeiträge der Scientists for Future 9: 1–98. (Note:The article is in German, but provides a long English abstract.) ZUSAMMENFASSUNG (English further below): Angesichts der sich beschleunigenden Klimakrise wird die Bedeutung der Kernkraft, die derzeit ca. 10 % der weltweiten Stromproduktion ausmacht, für den zukünftigen Energieträgermix diskutiert. Einige Länder, internationale Organisationen, private Unternehmen sowie Forscher:innen messen der Kernenergie auf dem Weg zur Kli­ma­neutralität und zum Ende fossiler Energien eine gewisse Bedeutung bei. Dies geht auch aus Energie- und Klimaszenarien des IPCC hervor. Dagegen legen die Er­fahrun­gen mit der kommerziellen Nutzung der Kernkraft der letzten sieben Jahr­zehnte nahe, dass ein solcher Pfad mit erheblichen technischen, ökonomischen und gesell­schaftlichen Risiken verbunden ist. Der vorliegende Diskussionsbeitrag erör­tert Ar­gumente in den Bereichen "Technologie und Gefahrenpotenziale", "Wirt­schaftlich­keit", "zeitliche Verfügbarkeit" sowie "Kompatibilität mit der sozial-ökolo­gischen Transformation" und zieht dann ein Fazit. Technologie und Gefahrenpotenziale: In Kernkraftwerken sind jederzeit katastro­phale Unfälle mit großen Freisetzungen radioaktiver Schadstoffe möglich. Dies zei­gen nicht nur die Großunfälle, z. B. die Ka­ta­strophen von Tschernobyl und Fukushima, sondern auch eine Vielzahl von Un­fäl­len, die sich seit 1945 in jedem Jahrzehnt und in jeder Region, die Kernenergie nutzt, ereignet haben. Von in Planung befindlichen SMR-Reaktorkonzepten ("Small Modu­lar Reactors") ist keine wesentlich größere Zuver­lässigkeit zu erwarten. Darüber hinaus besteht permanent die Gefahr des Miss­brauchs von waffenfähigem Spaltmaterial (hochangereichertes Uran bzw. Plu­to­nium) für terroristische Zwecke oder andere Proliferation. Die Endlagerung hoch­radio­aktiver Abfälle muss aufgrund hoher Halbwertszeiten für über eine Millio­n Jahre sicher gewähr­leistet werden; die damit verbundenen Langfristrisiken sind aus heu­tiger Per­spektive ...

In March 2019, German-speaking scientists and scholars calling themselves Scientists for Future, published a statement in support of the youth protesters in Germany, Austria, and Switzerland (Fridays for Future, Klimastreik/Climate Strike), verifying the scientific evidence that the youth protestors refer to. In this article, they provide the full text of the statement, including the list of supporting facts (in both English and German) as well as an analysis of the results and impacts of the statement. Furthermore, they reflect on the challenges for scientists and scholars who feel a dual responsibility: on the one hand, to remain independent and politically neutral, and, on the other hand, to inform and warn societies of the dangers that lie ahead. ; ISSN:0940-5550

In March 2019, German-speaking scientists and scholars calling themselves Scientists for Future, published a statement in support of the youth protesters in Germany, Austria, and Switzerland (Fridays for Future, Klimastreik/Climate Strike), verifying the scientific evidence that the youth protestors refer to. In this article, they provide the full text of the statement, including the list of supporting facts (in both English and German) as well as an analysis of the results and impacts of the statement. Furthermore, they reflect on the challenges for scientists and scholars who feel a dual responsibility: on the one hand, to remain independent and politically neutral, and, on the other hand, to inform and warn societies of the dangers that lie ahead. © 2019 G. Hagedorn et al.; licensee oekom verlag.This Open Access article is published under the terms of the Creative Commons Attribution License CCBY4.0 (http://creativecommons.org/licenses/by/4.0).