kopfgold.bsky.social
Mathematiker, Boomer. 𝓞𝓲𝓷𝓴𝓲𝓷𝓰 𝓽𝓱𝓻𝓸𝓾𝓰𝓱 𝓸𝓹𝓮𝓷 𝓬𝓸𝓾𝓷𝓽𝓻𝔂.
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@kopfgold@x.com
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In den Szenarien für 2045 stimmt die erste Aussage nicht mehr. Das Verbundnetz wird nicht reichen, wenn wir über Monate in Mangelzeiten große Energiemengen als Strom importieren müssten. Schau hier: bsky.app/profile/kopf...
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Weil man das Argument so nicht ganz ernstnehmen kann. Zumindest noch nicht.
Sowohl Uran als auch Gas lassen sich speichern, verbrauchen sich langsam. Strom muß zum Verbrauchszeitpunkt geliefert werden.
Das Lieferrisiko ist also beträchtlich. Der Angriff auf das Stromnetz leichter und desaströs.
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Frage an die 100%-EE-Blase: Wo kommt in 2045 eigentlich der Wasserstoff her, um das Energiedefizit im Strombereich auszugleichen?
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Hintergrund zu diesen Berechnungen: bsky.app/profile/kopf...
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Würden Sie dieses Energiedefizit weiterhin mit Erdgas- oder Wasserstoffimporten ausgleichen, oder würden Sie auf Stromimporte setzen, mit einer dazu notwendigen Importleistung von bis zu 83 GW?
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Dabei ist schon eine Wirkung von knapp 1 TWh an Batterien/DSM und die saisonale Speicherung der ∅ Überdeckung von 131 TWh/a mit Wasserstoff eingerechnet. Die ∅ Unterdeckung beträgt 166 TWh/a. ->
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Wenn ich Sie richtig verstanden habe, dann beziehen Sie sich auf das Szenario KNS2035. In diesem hätten wir in historischen Zeiten (1982-2016) ein durchschnittliches bilanzielles Energiedefizit im Strombereich von etwa 113 TWh/a gehabt. ->
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Thanks! Calculations and graphs are done in Julia with makie, tables with latex.
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Thanks for reading! First Photo by unsplash.com/@mirakemppai.... Here's the link to the first post for sharing: bsky.app/profile/kopf...
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Judging by needed storage capacities, power backup and import dependence we got a serious challenge at hand to make the system work. Clearly, it has to be viewed in the context of the European grid to at least partially alleviate energy deficits in Germany. 21/
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The energy deficit in a time period is calculated as the integral of smooth positive residual load minus .4 times the integral of smooth negative residual load. Here I assume a mean round trip efficiency of 40% for long term storage, e.g. electrolysers, H₂ storage and CCGTs. 20/
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Increasing the number of hours for smoothing has diminishing returns. Here the capacity is directly derived from the number of hours and is to be understood as a virtual value representing batteries and DSM together. The smoothing kernel above corresponds to 1.16 TWh: 19/
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Battery and DSM is simulated by smoothing residual load over 24 hours. In a sense this is best possible because it embodies perfect foresight and no losses. The width and shape of the smoothing kernel is up to debate though: 18/
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Some technical details: I validated the data I used against the overlapping period 2015-2016 of ENTSO-E and Smard databases: 17/
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Summary of a variety of scenarios for Germany in 2045: 16/
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Imports are determined by energy deficit. In the mean it turns out to be 269 TWh/a, 22% of mean yearly electricity generation. The maximum deficit in a single year is 344 TWh: 15/
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Backup power is determined by the maximum positive residual load encountered after batteries and DSM. It turns out to be 171 GW: 14/
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90 days: 13/
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30 days: 12/
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To determine storage size we must first define the length of a buffer period in which we aim to be independent from imports (if applicable) and then calculate the energy deficit. Inspired by Ruhnau & Qvist I have done this for periods of 10, 30 and 90 days. 10 days: 11/
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Now forget doldrum counting. The questions we *really* want to answer are: How much storage, how much backup power, how much energy import is necessary. Instead of using data to count DDs, why not address these questions directly? 10/
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I also counted the mean number of doldrum hours, days and weeks per year: 9/
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Last but not least a definition proposed by Solardoktor on https://buff.ly/3Pggcwj: A dd event is a period where residual load stays positive after smoothing with batteries and DSM. 8/
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A dd-event of type mbt10 (mean below threshold) is a period where mean wind and PV power is less than 10% of installed capacity.
7/
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Next two definitions by Ohlendorf & @wpschill.bsky.social, doi:10.1088/1748-9326/ab91e9. A doldrum hour is defined as an hour with mean wind and PV power of less than 10% of installed capacity. A dd event of type cbt10 (const. below threshold)
is a period of consecutive doldrum hours. 6/
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Probst & Burger define a doldrum day to be one where renewable production in average covers less that 20% of demand. Over 35 years we find the following: 5/
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Before counting one has to define the term dark doldrums quantitatively. I've looked at four ways to do it and will start with what @leonhardprobst.bsky.social & @energy-charts.bsky.social from Fraunhofer ISE put forward in this podcast: https://buff.ly/41SPgtN 4/
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The method of using reanalysis data is explained here ;) 3/
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I am basing the analysis on the "T45 Strom" scenario from "Langfristszenarien". Germany specific weather data is provided by ENTSO-E, the demand curve taken from @oliverruhnau.bsky.social & Staffan Qvist, doi:10.1088/1748-9326/ac4dc8. All calculation are to be taken as approximations ;) 2/
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For me abandoning soap and hot water turned out to be effective for reestablishing a healthy microbiome. I think about this a lot and always envision it battling nasty pathogens.
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Been thinking 'bout it all my life but always opted out because I wanted a respectable government job (professor)
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A similar statement could probably made for vehicle occupants and pedestrians too.
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Crisis with new boyfriend in 10 mins.
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How are the homemade cookies for welfare coming along? Has the city boyfriend with laptop and business casual attire shown up already?
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Happy that a more realistic perspective on distributed generation is evolving. For cities, power supply with local VRE always seemed niche to me.
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A common sight in our street: