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WEGE FÜR DIE ENERGIEWENDE Kosteneffiziente und klimagerechte Transformationsstrategien für das deutsche Energiesystem bis zum Jahr 2050

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WEGE FÜR DIE ENERGIEWENDE Kosteneffiziente und klimagerechte Transformationsstrategien für das deutsche Energiesystem bis zum Jahr 2050

Abstract

Deutschland hat sich zum Ziel gesetzt, die Treibhausgasemissionen bis zum Jahr 2050 um 80 bis 95 % gegenüber dem Emissionsniveau von 1990 zu reduzieren. Die hierfür festgelegten Treibhausgasreduktionspfade werden durch eine Vielzahl von weiteren zum Teil sehr detaillierten Zielsetzungen (z. B. Anteil erneuerbarer Energien an der Stromerzeugung) flankiert, die von der Bundesregierung als notwendig gesehen werden, um die übergeordneten Treibhausgasreduktionsziele zu erreichen. Dieser Zielekanon wurde im Laufe der letzten Dekade sukzessive entwickelt und erweitert. Viele vorliegende Studien, in denen Transformationspfade vorgeschlagen werden, integrieren diesen Zielkanon durch exogene Annahmen und schränken damit das Technikportfolio ein. Dies widerspricht einem Lösungsansatz, der sich vor allem durch Technologieoffenheit auszeichnen sollte. Die Frage, ob es sich bei den vorgeschlagenen Transformationspfaden um kostenoptimale Strategien handelt, bleibt in aller Regel unbeantwortet. Ziel der vorliegenden Studie ist es daher, die kosteneffizientesten CO2 Minderungsstrategien zur Erreichung der Klimaschutzziele Deutschlands bis zum Jahr 2050 zu identifizieren. Hierzu werden zwei CO2-Reduktionsszenarien analysiert, die sich ausschließlich an den Minderungszielen für das Jahr 2050 von -80 % (Szenario 80) und -95 % (Szenario 95) orientieren. Für die Analyse wird eine neuartige Modellfamilie eingesetzt, die am Forschungszentrum Jülich entwickelt wurde. Diese ermöglicht es, die nationale Energieversorgung in all ihren Wechselwirkungen und Pfaden abzubilden. Unter der Randbedingung der Einhaltung der Reduktionsziele lassen sich die kosteneffizientesten Maßnahmen bzw. Treibhausgasminderungsstrategien ermitteln. Die Kombination der verschiedenen eingesetzten Modelle, die sich durch unterschiedliche methodische Vorgehensweisen auszeichnen, erlaubt eine fundierte und tiefgehende Analyse von Treibhausgasminderungsstrategien. Die hohe zeitliche und räumliche Auflösung ermöglicht Aussagen zur Konzeption von zukünftigen Energieinfrastrukturen (Strom, Erdgas und Wasserstoff) sowie detaillierte Regionalanalysen eines möglichen Windkraft- sowie PV-Ausbaus. Darüber hinaus können zukünftige globale Energiemärkte (z. B. synthetische Kraftstoffe, synthetisches Methan, Wasserstoff) simuliert und mögliche Energieimporte und -exporte im Kontext der Energiewende abgeschätzt werden.
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Chapter
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