This study establishes a new approach to analyzing the economic impacts of vehicle-to-grid (V2G) regulation reserves by simulating the restrictions arising from unpredictable mobility requests by ...vehicle users. A case study for Germany using average daily values (in the following also called the "static" approach) and a dynamic simulation including different mobility use patterns are presented. Comparing the dynamic approach with the static approach reveals a significant difference in the power a vehicle can offer for ancillary services and provides insights into the necessary size of vehicle pools and possible adaptations required in the regulation market to render V2G feasible. In the static approach it is shown that negative secondary control is economically the most beneficial for electric vehicles because it offers the highest potential for charging with "low-priced" energy from negative regulation reserves. A Monte Carlo simulation using stochastic mobility behavior results in a 40% reduction of the power available for regulation compared to the static approach. Because of the high value of power in the regulation market, this finding has a strong impact on the resulting revenues. Further, we demonstrate that, for the data used, a pool size of 10 000 vehicles seems reasonable to balance the variation in each individual's driving behavior. In the case of the German regulation market, which uses monthly bids, a daily or hourly bid period is recommended. This adaptation would be necessary to provide individual regulation assuming that the vehicles are primarily used for mobility reasons and cannot deliver the same amount of power every hour of the week.
Data from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition allowed us to investigate the temporal dynamics of snowfall, snow accumulation and erosion in ...great detail for almost the whole accumulation season (November 2019 to May 2020). We computed cumulative snow water equivalent (SWE) over the sea ice based on snow depth and density retrievals from a SnowMicroPen and approximately weekly measured snow depths along fixed transect paths. We used the derived SWE from the snow cover to compare with precipitation sensors installed during MOSAiC. The data were also compared with ERA5 reanalysis snowfall rates for the drift track. We found an accumulated snow mass of 38 mm SWE between the end of October 2019 and end of April 2020. The initial SWE over first-year ice relative to second-year ice increased from 50 % to 90 % by end of the investigation period. Further, we found that the Vaisala Present Weather Detector 22, an optical precipitation sensor, and installed on a railing on the top deck of research vessel Polarstern, was least affected by blowing snow and showed good agreements with SWE retrievals along the transect. On the contrary, the OTT Pluvio2 pluviometer and the OTT Parsivel2 laser disdrometer were largely affected by wind and blowing snow, leading to too high measured precipitation rates. These are largely reduced when eliminating drifting snow periods in the comparison. ERA5 reveals good timing of the snowfall events and good agreement with ground measurements with an overestimation tendency. Retrieved snowfall from the ship-based Ka-band ARM zenith radar shows good agreements with SWE of the snow cover and differences comparable to those of ERA5. Based on the results, we suggest the Ka-band radar-derived snowfall as an upper limit and the present weather detector on RV Polarstern as a lower limit of a cumulative snowfall range. Based on these findings, we suggest a cumulative snowfall of 72 to 107 mm and a precipitation mass loss of the snow cover due to erosion and sublimation as between 47 % and 68 %, for the time period between 31 October 2019 and 26 April 2020. Extending this period beyond available snow cover measurements, we suggest a cumulative snowfall of 98–114 mm.
To improve our understanding of how snow properties influence sea ice thickness retrievals from presently operational and upcoming satellite radar altimeter missions, as well as to investigate the ...potential for combining dual frequencies to simultaneously map snow depth and sea ice thickness, a new, surface-based, fully polarimetric Ku- and Ka-band radar (KuKa radar) was built and deployed during the 2019–2020 year-long MOSAiC international Arctic drift expedition. This instrument, built to operate both as an altimeter (stare mode) and as a scatterometer (scan mode), provided the first in situ Ku- and Ka-band dual-frequency radar observations from autumn freeze-up through midwinter and covering newly formed ice in leads and first-year and second-year ice floes. Data gathered in the altimeter mode will be used to investigate the potential for estimating snow depth as the difference between dominant radar scattering horizons in the Ka- and Ku-band data. In the scatterometer mode, the Ku- and Ka-band radars operated under a wide range of azimuth and incidence angles, continuously assessing changes in the polarimetric radar backscatter and derived polarimetric parameters, as snow properties varied under varying atmospheric conditions. These observations allow for characterizing radar backscatter responses to changes in atmospheric and surface geophysical conditions. In this paper, we describe the KuKa radar, illustrate examples of its data and demonstrate their potential for these investigations.
Wind-driven redistribution of snow on sea ice alters its
topography and microstructure, yet the impact of these processes on radar
signatures is poorly understood. Here, we examine the effects of ...snow
redistribution over Arctic sea ice on radar waveforms and backscatter
signatures obtained from a surface-based, fully polarimetric Ka- and Ku-band
radar at incidence angles between 0∘ (nadir) and 50∘.
Two wind events in November 2019 during the Multidisciplinary drifting Observatory for
the Study of Arctic Climate (MOSAiC) expedition are evaluated. During both events, changes in Ka- and
Ku-band radar waveforms and backscatter coefficients at nadir are observed,
coincident with surface topography changes measured by a terrestrial laser
scanner. At both frequencies, redistribution caused snow densification at
the surface and the uppermost layers, increasing the scattering at the
air–snow interface at nadir and its prevalence as the dominant radar scattering surface. The waveform data also detected the presence of previous
air–snow interfaces, buried beneath newly deposited snow. The additional
scattering from previous air–snow interfaces could therefore affect the
range retrieved from Ka- and Ku-band satellite altimeters. With increasing
incidence angles, the relative scattering contribution of the air–snow
interface decreases, and the snow–sea ice interface scattering increases.
Relative to pre-wind event conditions, azimuthally averaged backscatter at
nadir during the wind events increases by up to 8 dB (Ka-band) and 5 dB (Ku-band). Results show substantial backscatter variability within the scan
area at all incidence angles and polarizations, in response to increasing
wind speed and changes in wind direction. Our results show that snow
redistribution and wind compaction need to be accounted for to interpret
airborne and satellite radar measurements of snow-covered sea ice.
Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC)(3) project was established in 2016 (www.ac3-tr.de/). It comprises modeling and ...data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, shipborne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data. For example, a distinct atmospheric moistening, an increase of regional storm activities, an amplified winter warming in the Svalbard and North Pole regions, and a decrease of sea ice thickness in the Fram Strait and of snow depth on sea ice have been identified. A positive trend of tropospheric bromine monoxide (BrO) column densities during polar spring was verified. Local marine/biogenic sources for cloud condensation nuclei and ice nucleating particles were found. Atmospheric-ocean and radiative transfer models were advanced by applying new parameterizations of surface albedo, cloud droplet activation, convective plumes and related processes over leads, and turbulent transfer coefficients for stable surface layers. Four modes of the surface radiative energy budget were explored and reproduced by simulations. To advance the future synthesis of the results, cross-cutting activities are being developed aiming to answer key questions in four focus areas: lapse rate feedback, surface processes, Arctic mixed-phase clouds, and airmass transport and transformation.
Abstract Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC) 3 project was established in 2016 ( www.ac3-tr.de/ ). It comprises ...modeling and data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, shipborne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data. For example, a distinct atmospheric moistening, an increase of regional storm activities, an amplified winter warming in the Svalbard and North Pole regions, and a decrease of sea ice thickness in the Fram Strait and of snow depth on sea ice have been identified. A positive trend of tropospheric bromine monoxide (BrO) column densities during polar spring was verified. Local marine/biogenic sources for cloud condensation nuclei and ice nucleating particles were found. Atmospheric–ocean and radiative transfer models were advanced by applying new parameterizations of surface albedo, cloud droplet activation, convective plumes and related processes over leads, and turbulent transfer coefficients for stable surface layers. Four modes of the surface radiative energy budget were explored and reproduced by simulations. To advance the future synthesis of the results, cross-cutting activities are being developed aiming to answer key questions in four focus areas: lapse rate feedback, surface processes, Arctic mixed-phase clouds, and airmass transport and transformation.
Klimarelevanz des Abwassersektors Tauber, Joseph; Krampe, Jörg; Parravicini, Vanessa
Österreichische Wasser- und Abfallwirtschaft,
2023/4, Letnik:
75, Številka:
3-4
Journal Article
Recenzirano
Odprti dostop
Zusammenfassung
Abwasserkanäle und Abwasserreinigungsanlagen können relevante Quellen von Kohlendioxid, Lachgas und Methan sein. Direkte Kohlendioxidemissionen sind klimaneutral, da die organischen ...Bestandteile im Abwasser überwiegend aus biologischen Quellen stammen. Dagegen haben direkte Methan- und Lachgas-Emissionen einen signifikanten Einfluss auf das Klima. Der derzeit vorliegende Entwurf der EU-Richtlinie für kommunales Abwasser 91/271/EWG (Urban Wastewater Treatment Directive) greift erstmals Treibhausgasemissionen aus Abwasserkanälen und Kläranlagen auf und zielt auf deren Monitoring, Reporting und Reduktion ab. Die vorliegende Arbeit beschäftigt sich mit den direkten Gasemissionen von Methan und Lachgas aus Abwasserkanälen und Kläranlagen und deren Produktions- und Reduktionspfaden. Die Hauptemissionsquellen werden überblicksartig dargestellt und die Bedeutung dieser Emissionen wird auf nationaler Ebene eingeordnet. Potenziale und Maßnahmen zur Reduktion von Methan- und Lachgasemissionen aus dem Sektor Abwasser werden beleuchtet. Indirekte Treibhausgasemissionen aus dem Bezug von Strom sowie aus vorgelagerten Prozessen, wie z. B. aus der Herstellung und Transport von Fällmitteln, stellen auch wesentliche Emissionspfade dar. Die Relevanz der unterschiedlichen Treibhausgas-Emissionspfade der Abwasserentsorgung werden am Beispiel des CO
2
-Fußabdrucks von zwei Kläranlagen, einer mit simultaner aerober Schlammstabilisierung (SASS) und einer mit anaerober Stabilisierung (Schlammfaulung) diskutiert.
Zusammenfassung
Der Kommissionsvorschlag für die kommunale Abwasserrichtlinie schreibt die Implementierung einer 4. Reinigungsstufe vor, wenn bestimmte Kriterien erfüllt sind. Dementsprechend müssen ...große Kläranlagen (≥ 100.000 EW) sowie Anlagen ≥ 10.000 EW, die in spurenstoffempfindliche Gebiete einleiten, ausgebaut werden, um eine 80 %ige Entfernung, gemittelt über mindestens sechs Indikatorsubstanzen zu erreichen. Schätzungen für Österreich reichen von 93 bis 278 auszurüstende Kläranlagen. 278 ist eine Maximalbetrachtung ohne vorherige Risikobewertung und unter Annahme der neu vorgeschlagenen Umweltqualitätsnormen. Sowohl die Ozonung als auch die Aktivkohlebehandlung sind geeignet, um die Mindestanforderungen zu erreichen. Die spezifischen jährlichen Kosten können anhand einer einfachen Funktion grob abgeschätzt werden und liegen bei 16, 8 und 4 €/EW/a für Anlagen mit 10.000, 50.000 oder 200.000 EW
Ausbau
. Die Wechselwirkung mit anderen EU-Rechtsvorschriften und aktuellen Themen der Abwasserreinigung birgt sowohl Synergien, wie z. B. eine solide Grundlage für die weitere Aufbereitung zur Wasserwiederverwendung für die landwirtschaftliche Bewässerung, als auch Herausforderungen, z. B. für die neu vorgeschlagenen strengeren Umweltqualitätsnormen für per- und polyfluorierte Alkylsubstanzen.
In this contribution, we analyse scenarios of advanced wastewater treatment for the removal of micropollutants. By this we refer to current mainstream, broad spectrum processes including ozonation ...and sorption onto activated carbon. We argue that advanced treatment requires properly implemented tertiary (nutrient removal) treatment in order to be effective. We review the critical aspects of the main advanced treatment options, their advantages and disadvantages. We propose a quantification of the costs of implementing advanced treatment, as well as upgrading plants from secondary to tertiary treatment when needed, and we illustrate what drives the costs of advanced treatment for a set of standard configurations. We propose a cost function to represent the total costs (investment, operation and maintenance) of advanced treatment. We quantify the implications of advanced treatment in terms of greenhouse gas emissions. Based on the indicators of total toxic discharge, toxicity at the discharge points and toxicity across the stream network discussed in Pistocchi et al. (2022), we compare costs and effectiveness of different scenarios of advanced treatment. In principle the total toxic load and toxicity at the points of discharge could be reduced by about 75 % if advanced treatment processes were implemented virtually at all wastewater treatment plants, but this would entail costs of about 4 billion euro/year for the European Union as a whole. We consider a “compromise” scenario where advanced treatment is required at plants of 100 thousand population equivalents (PE) or larger, or at plants between 10 and 100 thousand PE if the dilution ratio at the discharge point is 10 or less. Under this scenario, the length of the stream network exposed to high toxicity would not increase significantly compared to the previous scenario, and the other indicators would not deteriorate significantly, while the costs would remain at about 1.5 billion Euro/year. Arguably, costs could be further reduced, without a worsening of water quality, if we replace a local risk assessment to generic criteria of plant capacity and dilution in order to determine if a WWTP requires advanced treatment.
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•Cost/effectiveness of advanced treatment scenarios for wastewater micropollutants.•Pollution down by 75 % with advanced treatment everywhere, but costs ~4 bn €/y•Acceptably protective, “compromise” scenario costs about 1.5 bn €/y.•Large plants should treat, risk assessment to decide on treatment at a small plant.
The inactivation of antibiotic resistant bacteria (ARB) and genes (ARGs) in an advanced plant combining ozonation and granular activated carbon (GAC) filtration applied for effluent after ...conventional activated sludge treatment at a full-scale urban wastewater treatment plant was investigated for over 13 consecutive months. The nitrite compensated specific ozone dose ranged between 0.4 and 0.7 g O3/g DOC with short-time sampling campaigns (0.2–0.9 g O3/g DOC). Samples were analysed with culture-dependent methods for bacterial targets and with qPCR for genes. The log removal values were correlated with a decrease of the matrix UV absorption at 254 nm (ΔUV254) and indicated a range of ΔUV254 that corresponds to a sufficient membrane damage to affect DNA. For trimethoprim/sulfamethoxazole resistant E. coli, sul1, ermB and tetW, this phase was observed at ΔUV254 of ~30 % (~0.5 g O3/g DOC). For ampicillin resistant E. coli and blaTEM-1, it was observed around 35–40 % (~0.7 g O3/g DOC), which can be linked to mechanisms related to oxidative damages in bacteria resistant to bactericidal antibiotics. GAC treatment resulted in a further abatement for trimethoprim/sulfamethoxazole E. coli, sul1 and tetW, and in increase in absolute and relative abundance of ermB and blaTEM-1.
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•Ozonation and GAC were evaluated for ARB and ARGs abatement in a long-term study.•Ozone doses ≥ 0.6 g O3/g DOC were required to affect tested DNA targets.•Ampicillin resistant E. coli was less susceptible to ozonation effects than other ARB.•A relative abundance of blaTEM-1 gene increased after GAC treatment.•ΔUV254 was tested as a proxy parameter to indicate DNA damage by ozone.
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