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The quantification of emissions of greenhouse gases and air pollutants through the inversion of plumes in satellite images remains a complex problem that current methods can only assess with significant uncertainties. The anticipated launch of the CO2M satellite constellation in 2026 is expected to provide high-resolution images of CO2 column-averaged mole fractions (XCO2), opening up new possibilities. However, the inversion of future CO2 plumes from CO2M will encounter various obstacles. A challenge is the CO2 plume low signal-to-noise ratio, due to the variability of the background and instrumental errors in satellite measurements. Moreover, uncertainties in the transport and dispersion processes further complicate the inversion task. To address these challenges, deep learning techniques, such as neural networks, offer promising solutions for retrieving emissions from plumes in XCO2 images. Deep learning models can be trained to identify emissions from plume dynamics simulated using a transport model. It then becomes possible to extract relevant information from new plumes and predict their emissions. In this paper, we employ convolutional neural networks (CNN) to estimate the emission fluxes from a plume in a pseudo XCO2 image. Our dataset used to train and test such methods includes pseudo images based on simulations of hourly XCO2, NO2 and wind fields near various power plants in Eastern Germany, tracing plumes from anthropogenic and biogenic sources. CNN models are trained to predict emissions from three power plants that exhibit diverse characteristics. The power plants used to assess the deep learning model's performance are not used to train the model. We find that the CNN model outperforms state of the art plume inversion approaches, achieving highly accurate results with an absolute error about half of that of the cross-sectional flux method. Furthermore, we show that our estimations are only slightly affected by the absence of NO2 fields or a detection mechanism as additional information. Finally, interpretability techniques applied to our models confirm that the CNN automatically learns to identify the XCO2 plume and to assess emissions from the plume concentrations. These promising results suggest a high potential of CNNs in estimating local CO2 emissions from satellite images. [ABSTRACT FROM AUTHOR]

This paper identifies socioeconomic factors that are supposed to impact the investment decision of private households in Germany regarding small-scale solar PV (photovoltaic) systems. In 2022, the last nuclear power plant will phase out and the end of coal-fired power plants is fixed for 2038. Thus, the legislator is mandated to foster the addition of renewable energy capacities to close the gap fossil fuels and nuclear power leaves. Some share of the renewable energies could be from private households that mainly invest in small-scale solar PV systems. To stimulate investments, it is necessary to identify factors that are important for the investment decisions of private households. Within this paper, secondary socioeconomic data for the period from 2009–2018 was compiled. In order to identify the latent variables, a factor analysis was conducted. The results state five factors that are supposed to impact the investment decisions of the prosumer in Germany. [ABSTRACT FROM AUTHOR]

This Comment provides a comprehensive legal analysis of the potential investor-state disputes arising from Germany's groundbreaking Coal Exit Act, which utilizes reverse auctions to phase out coal-fired power plants. The study investigates potential breaches of the Energy Charter Treaty (ECT), focusing on Article 10(1), the fair and equitable treatment clause, and Article 13(1), the expropriation clause. The reverse auction mechanism, when examined under ECT provisions, could be perceived as both a breach of fair and equitable treatment and an unlawful, indirect expropriation, substantially depriving investors of the value of their investments. The analysis also delves into Germany's possible defenses to a prospective claim, including jurisdictional objections, waiver clauses in buyout contracts, exceptions for necessary regulations in the ECT, and withdrawal from the ECT altogether. Findings suggest that investor-state claims can feasibly proceed in response to Germany's coal phase-out policy. Accordingly, policymakers should factor in the costs of Investor-State Dispute Settlement (ISDS) when estimating the cost-saving potential of reverse auctions as a means to phase out high emissions assets like coal-fired powerplants. The Comment concludes by proposing a more efficient buyout transaction structure that leverages carbon markets to enable comparable emissions reductions at a lower marginal cost of abatement and reduce the state's exposure to ISDS claims. [ABSTRACT FROM AUTHOR]

Thermal-based power stations rely on water for cooling purposes. These water sources may be subject to incidents of scarcity, environmental regulations, and competing economic concerns. This paper analyzes the effect of water scarcity and increased river temperatures on German electricity prices from 2002 to 2009. Having controlled for demand effects, the results indicate that the electricity price is significantly impacted by both a change in river temperatures and the relative abundance of river water. An implication is that future climate change will affect electricity prices not only through changes in demand, but also via increased water temperatures and scarcity. [ABSTRACT FROM AUTHOR]

The energy industry is undergoing a major upheaval. In Germany, for example, the large nuclear and coal-fired power plants in the gigawatt scale are planned to be shut down in the forthcoming years. Electricity is to be generated in many small units in a decentralized, renewable and environmentally friendly manner. The large 1000 MW multistage axial steam turbines used to this date are no longer suitable for these tasks. For this reason, the authors examine turbine architectures that are known per se but have fallen into oblivion due to their inferior efficiency and upcoming electric drives about 100 year ago. However, these uncommon turbine concepts could be suitable for small to micro scale distributed power plants using thermodynamic cycles, which use for example geothermal wells or waste heat from industry to generate electricity close to the consumers. Thus, the paper describes and discusses the concept of a velocity-compounded single wheel re-entry cantilever turbine in comparison with other turbine concepts, especially other velocity-compounded turbines like the Curtis-type. Furthermore, the authors describe the design considerations, which led to a specific design of a 5 kW air turbine demonstrator, which was later manufactured and investigated. Finally, first numerical as well as experimental results are presented, compared and critically discussed with regards to the originally defined design approach. [ABSTRACT FROM AUTHOR]

The nuclear phase‐out in Germany and the decarbonization of the energy supply are accompanied by a profound upheaval of the generation fleet. The decommissioning of large power plants and their replacement by decentralized, renewable generation plants (DG) as well as storage facilities leads to a shift in generation output from power plants connected to the transmission grid to a large number of renewable and decentralized plants connected to the distribution grids. This significantly impacts the approach to restore the interconnected system after a large‐scale blackout. In order to be able to plan and instruct the dispatch of generating power from the network operator's control centres when restoring the grid after a large‐scale blackout, two aggregation and forecasting methods differentiated by voltage level are presented. For larger farms connected to the high‐voltage grid, a structure‐based node approach is chosen; for the multitude of small and microunits connected to the medium‐ and low‐voltage grids, an area‐based approach is used. These methods do provide the network operator with active power/frequency management in the medium and long‐term range. The provision of fast frequency response (FFR) by inverter‐coupled units or storage systems stabilizes the frequency in the short‐term range. In this way, the frequency nadir following a load connection can be mitigated during network restoration, which accelerates the process. This is particularly relevant against the background of the nuclear and coal phase‐out, as it can compensate for the reduction in inertia and controllable feed‐in power caused by power plant shutdowns. In a case study, it is shown that in a grid island typical for the early phase of network restoration, the inertia of a 500 MW coal‐fired power plant can almost be replaced by a battery storage system of 50 MW which provides FFR. [ABSTRACT FROM AUTHOR]

Across Germany, coal-fired power plants will be shut down not later than 2038. In the Rhine-Ruhr area of western Germany, their waste heat is the main supply for one of Europe's largest district heating networks. Because of the projected shutdown of coal-fired power plants, sustainable alternatives must be implemented. This paper evaluates the hydrothermal potential of Devonian carbonates. A depofacies and mineralogy model is proposed and discussed. Tentative conclusions are drawn based on petrophysical laboratory tests. Extrapolating the thermal and hydraulic rock properties into geothermal reservoir depths offers constraints for associated reservoir simulations. This task applies existing and derived extrapolation equations taking local pressure and temperature gradients into consideration. The change from a non-linear to a linear development at the critical crack-closure pressure provides evidence regarding the petrophysical in-situ reservoir conditions. Results show a positive effect of increased dolomite volumes on reservoir properties. The spatial distribution of fracture networks significantly affects the geothermal reservoir potential, whereas the impact of regionally distributed depofacies variations is moderate. The critical crack-closure pressure equals 40 MPa for limestones and 60 MPa for dolomitic limestones, as well as dolostones, representing depths of approx. 3.6 and 5.4 km, respectively. At depths of 6 km, non-linear and linear extrapolation principles must be applied accordingly. At that depth, the thermal conductivity decreases by 14 to 20% compared to the outcrop values, depending on the sample category. The equivalent decrease in porosity amounts to one to two orders of magnitude. The permeability decrease equals three to four orders of magnitude. The petrophysical values of outcrop samples discussed here plot, within the error range, in the same domain as those of the Malm carbonates in the Munich area. Results are considered encouraging for those concerned with the sustainable transition of the district heating network in the Rhine-Ruhr area. Side-strands of regionally important fault systems, often characterised by hydrothermal dolomitisation, combine tectonic and petrophysical aspects that are advantageous and highly relevant for hydrothermal operations. • Devonian Massenkalk carbonates exhibit promising geothermal reservoir properties. • Fracture peculiarities are crucial for the hydraulic reservoir potential. • Dolomitisation further enhances the reservoir potential of Massenkalk carbonates. • Pressure effect on hydraulic properties is crucial for extrapolation models. [ABSTRACT FROM AUTHOR]

Background: In order to achieve the German greenhouse gas reduction targets, in particular, CO2 emissions of coal-fired power plants must be reduced. The co-incineration of biomass-based substitutes, here referred to as co-firing, is regarded as a highly cost-effective and short-term method of reducing CO2 emissions in the electricity sector. Another advantage of co-firing is its ability to meet base load demands and offer controllability. In this paper, we, therefore, evaluate the effectiveness of co-firing as a CO2 mitigation strategy in the German electricity sector by 2020. Methods: We consider the co-firing of three different substitutes: wood chips, industry pellets and torrefied biomass. Likewise, a comparison with three alternative mitigation strategies is part of the evaluation. We use seven sustainability indicators covering social, ecological and economic aspects as the basis for the evaluation. These sustainability indicators are determined by means of a merit order model, which enables us to simulate the electricity market in 2020 on an hourly basis and adjust it based on the assumption of widespread implementation of co-firing or one of the alternative mitigation strategies. Results: Our results show that all mitigation strategies have a significant potential to reduce the CO2 emissions of the electricity sector. Compared with the alternative mitigation strategies, co-firing is characterised on the one hand by rather low mitigation potentials and on the other hand by low CO2 mitigation costs. The co-firing of industry pellets appears to have the most advantageous combination of mitigation potential and mitigation costs. Conclusions: The widespread implementation of co-firing with industry pellets until 2020 would have led to 21% reduction in CO2 emissions on average. Nevertheless, it cannot be implemented immediately because time is needed for political decisions to be taken and, afterwards, for the technical retrofitting of power plants. Co-firing will, therefore, not be available to contribute to the achievement of the greenhouse gas reduction targets for the year 2020. However, our approach can be used to assess the contribution of the various CO2 mitigation strategies to the ambitious mitigation targets for the year 2030. [ABSTRACT FROM AUTHOR]

Summary: Fluctuating residual loads force lignite‐ and hard‐coal‐fired power plants to operate at technical and economical limitations. Energy storage systems (ESS) could resolve the plant‐design restrictions and enlarge the overall bandwidth of operation. Therefore, the electricity during minimum load can be stored and later fed into the grid. For this, the occurrence of minimum loads which could enable the periodic charging of ESS is analyzed at the example of lignite‐ and hard‐coal‐fired power plants in Germany. The durations of the minimum loads show marginal deviations within the considered years, as the median varies between 3 and 4 hours. The median of hard coal is 4 hours and for lignite, between 2 and 3 hours, respectively. In contrast to hard coal, the number of minimum loads of lignite increases slightly from 2016 to 2018. In total, the number and duration of minimum loads of both generation types are aligning within all transmission system areas. This is an indication that lignite power plants are increasingly affected by the merit‐order and are gradually being forced to operate more flexibly. Based on the analysis, a rough estimate of a suitable storage size for the integration of an ESS technology was derived for an exemplary power plant. [ABSTRACT FROM AUTHOR]

Abstract: Vattenfall is presently taking an experimental large-scale pilot test facility into operation for the detailed investigation of the oxyfuel firing process. The plant is located southeast of Berlin in Germany in the vicinity of the existing lignite-fired power plant Schwarze Pumpe. The oxyfuel pilot plant consists of a single 30MWth, top-mounted, PF burner and the subsequent flue gas cleaning equipment, electrostatic precipitator, wet flue gas desulpherization and the flue gas condenser. In addition to these components, a CO2 separation plant is placed downstream of the flue gas condenser to produce liquid CO2. A cryogenic air separation unit located at the site will supply gaseous oxygen with a minimum purity of 99,5% needed for the combustion. The burner is designed for both pre-dried lignite and bituminous coal which will be tested in a later phase. The construction started in January 2007 and the first major test phase is planned to start in November 2008. The liquid CO2 is planned to be used for test injections to qualify the Altmark gas field in Germany as a storage site for CO2 for up-coming carbon capture and storage projects and to investigate opportunities for enhanced gas recovery. This paper will present some background information and describe the planned measurements. Initial experiences from the commissioning of the pilot plant will be presented. [Copyright &y& Elsevier]

Coal-fired power plants are responsible for around a third of the total carbon dioxide emissions in Germany. Failure to reduce the persistently high level of coal-based power generation puts Germany's climate targets for 2020 and 2050 at risk and undermines a sustainable energy transition. Calculations by DIW Berlin and other expert opinions prove that, in the long term, lignite in particular will no longer be relevant to Germany's energy mix. However, if the prices for CO2 emissions allowances in the European Emissions Trading System do not rise considerably in the foreseeable future, a market-driven transition from coal to less CO2-intensive energy sources such as natural gas is unlikely to occur. Besides reforming the European Emissions Trading System, various other ways of reducing coal-based power generation are currently under discussion. These include the introduction of minimum efficiency levels or stricter flexibility requirements, national minimum prices for CO2 emissions allowances, capacity mechanisms, a residual emissions cap for coal-fired power plants, CO2 emissions performance standard, and network development planning that respects climate targets. These proposals apply to both new and existing coal-fired power plants. [ABSTRACT FROM AUTHOR]

Currently, in ten coal-fired power plants in Germany solid recovered fuels from mixed municipal waste and production-specific commercial waste are co-combusted and experiments have been conducted at other locations. Overall, in 2010 approximately 800 000 tonnes of these solid recovered fuels were used. In the coming years up to 2014 a slight decline in the quantity of materials used in co-combustions is expected. The co-combustion activities are in part significantly influenced by increasing power supply from renewable sources of energy and their impact on the regime of coal-fired power plants usage. Moreover, price trends of CO2 allowances, solid recovered fuels as well as imported coal also have significant influence. In addition to the usage of solid recovered fuels with biogenic content, the co-combustion of pure renewable biofuels has become more important in coal-fired power plants. The power plant operators make high demands on the quality of solid recovered fuels. As the operational experience shows, a set of problems may be posed by co-combustion. The key factors in process engineering are firing technique and corrosion. A significant ecological key factor is the emission of pollutants into the atmosphere. The results of this study derive from research made on the basis of an extensive literature search as well as a survey on power plant operators in Germany. The data from operators was updated in spring 2011. [ABSTRACT FROM AUTHOR]

In the not too distant future several power plants throughout Europe will have to be replaced and the decision has to be made whether to build coal-fired power plants with carbon capture and storage (CCS). In a study for the city of Kiel in northern Germany only an 800 MW coal power plant reaches a required minimum for rentability. This study looks at an additional economic and environmental evaluation of a coal plant with CCS. We find that in two out of three carbon and energy price scenarios integrated gasification combined cycle (IGCC) plants with CCS have the greatest rentability. Pulverised coal (PC) plants with CCS can only compete with other options under very favourable assumptions. Life-cycle emissions from CCS are less than 70% of a coal plant - compared with at least more than 80% when only considering direct emissions from plants. However, life-cycle emissions are lower than in any other assessed option. [ABSTRACT FROM AUTHOR]

The article cites a study which assesses the bone fluoride concentrations in roe deer and the degree of fluoride deposition into a wildlife habitat near a brown coal-fired power plant in Germany. The examination on the skeletal fluoride content of wild deer for the period of 1973-1986 and the following period of 1987-1998 found that its concentration on deer population decreased to a level which was slightly higher from those found in European regions. The skeletal fluoride concentration in stags from the polluted areas was 1448 parts per million (ppm), while only 322 ppm on those that came from unpolluted areas.

The article reports that Germany's Commission on Growth, Industry Restructuring and Employment published its final report, suggesting that the country phase out coal power production by 2038. Topics include the document, presented to the public on January 26, 2019 recommends replacing most of today's generation capacity with gas-fired power plants and technologies available in Germany's coal mining regions today and could provide them with excellent opportunities for job creation.