TY - JOUR A1 - Fuss, Sabine A1 - Flachsland, Christian A1 - Koch, Nicolas A1 - Kornek, Ulrike A1 - Knopf, Brigitte A1 - Edenhofer, Ottmar T1 - A Framework for Assessing the Performance of Cap-and-Trade Systems: Insights from the European Union Emissions Trading System JF - Review of Environmental Economics and Policy N2 - The performance of the European Union (EU) Emissions Trading System (ETS) and other cap-and-trade schemes has been under scrutiny because of their inability to create a stable price for greenhouse gas emissions. This article seeks to inform the often confusing debate about the economic performance of cap-and-trade systems over time, with a focus on the EU ETS. Based on a simple intertemporal framework of emissions trading and a review of the literature, we show that different frameworks and notions of efficiency result in both different assessments of performance and different recommended strategies for improving performance. More specifically, we argue that if cap-and-trade systems have temporal flexibility (i.e., they include banking and borrowing of emissions allowances), it can be highly misleading to base the economic assessment on short-term efficiency. We seek to draw attention to the concept of long-term economic performance, which takes into account the intertemporal nature of emissions trading systems. In particular, we identify market and government distortions (e.g., myopia, lack of policy credibility, excessive discounting) that may depress allowance prices and hamper intertemporal efficiency. We then examine whether the recently adopted Market Stability Reserve and the alternative price collar are likely to address these distortions. Y1 - 2018 U6 - https://doi.org/10.1093/reep/rey010 SN - 1750-6816 VL - 12 IS - 2 SP - 220 EP - 241 ER - TY - JOUR A1 - Edenhofer, Ottmar A1 - Knopf, Brigitte A1 - Burghaus, Kerstin A1 - Flachsland, Christian A1 - Jakob, Michael A1 - Koch, Nicolas T1 - Shifting Paradigms in Carbon Pricing JF - Intereconomics N2 - Carbon pricing is essential to achieve a reduction in global CO2 emissions. A carbon price can either be set directly via a carbon tax (price control) or be achieved through a cap-and-trade system (quantity control). While there has been much debate about the relative merits of each approach, cap-and-trade systems have been favoured in the political arena. In principle, they offer the most straightforward way to achieve a country’s emission reduction target by simply setting the cap at the remaining emission budget. Existing emissions trading schemes (ETSs) can be found in Europe, California and Québec, for example. Y1 - 2018 U6 - https://doi.org/10.1007/s10272-018-0735-6 VL - 53 IS - 3 SP - 135 EP - 140 ER - TY - RPRT A1 - Kalkuhl, Matthias A1 - Roolfs, Christina A1 - Edenhofer, Ottmar A1 - Haywood, Luke A1 - Heinemann, Maik A1 - Bekk, Anke A1 - Flachsland, Christian A1 - George, Jan A1 - Held, Anne A1 - aus dem Moore, Nils A1 - Luderer, Gunnar A1 - Koch, Nicolas A1 - Nikodinoska, Dragana A1 - Pahle, Michael A1 - Schill, Wolf-Peter A1 - Amberg, Maximilian A1 - Bergmann, Tobias A1 - Meyer, Henrika T1 - Reformoptionen für ein nachhaltiges Steuer- und Abgabensystem. Wie Lenkungssteuern effektiv und gerecht für den Klima- und Umweltschutz ausgestaltet werden können. Ein Ariadne-Kurzdossier. Y1 - 2021 UR - https://ariadneprojekt.de/media/2021/05/Ariadne-Kurzdossier_Steuerreform_Juni2021.pdf ER - TY - RPRT A1 - Khanna, Tarun A1 - Baiocchi, Giovanni A1 - Callaghan, Max W. A1 - Creutzig, Felix A1 - Bogdan Guias, Horia A1 - Haddaway, Neal A1 - Hirth, Lion A1 - Javaid, Aneeque A1 - Koch, Nicolas A1 - Laukemper, Sonja A1 - Loeschel, Andreas A1 - Del Mar Zamora, Maria A1 - Minx, Jan C. T1 - Reducing carbon emissions of households through monetary incentives and behavioral interventions: a meta-analysis N2 - Despite the importance of evaluating all mitigation options so as to inform policy decisions addressing climate change, a systematic analysis of household-scale interventions to reduce carbon emissions is missing. Here, we address this gap through a state-of-the-art machine-learning assisted meta-analysis to comparatively assess the effectiveness of a range of monetary and behavioral interventions in energy demand of residential buildings. We identify 122 studies and extract 360 effect sizes representing trials on 1.2 million households in 25 countries. We find that all the studied interventions reduce energy consumption of households. Our meta-regression evidences that monetary incentives are on an average more effective than behavioral interventions, but deploying the right combinations of interventions together can increase overall effectiveness. We estimate global cumulative emissions reduction of 8.64 Gt CO2 by 2040, though deploying the most effective packages and interventions could result in greater reduction. While modest, this potential should be viewed in conjunction with the need for de-risking mitigation with energy demand reductions and realizing substantial co-benefits.  Y1 - 2021 U6 - https://doi.org/10.21203/rs.3.rs-124386/v1 ER - TY - RPRT A1 - Edmondson, Duncan A1 - Flachsland, Christian A1 - aus dem Moore, Nils A1 - Koch, Nicolas A1 - Koller, Florian A1 - Gruhl, Henri A1 - Brehm, Johannes A1 - Levi, Sebastian T1 - Assessing Climate Policy Instrument Pathways: An Application to the German Light Duty Vehicle Sector T2 - Bewertung klimapolitischer Instrumentenmix-Pfade: Eine Anwendung auf leichte Nutzfahrzeuge in Deutschland KW - Centre for Sustainability Y1 - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b1570-opus4-47130 UR - https://ariadneprojekt.de/publikation/background-assessing-climate-policy-instrument-pathways-an-application-to-the-german-light-duty-vehicle-sector/ U6 - https://doi.org/10.48462/opus4-4713 N1 - This publication is also available in German at the link above. PB - Kopernikus-Projekt Ariadne CY - Potsdam ER - TY - RPRT A1 - Arlinghaus, Johanna A1 - Koch, Nicolas T1 - The welfare impact of using second-best uniform taxes to address traffic congestion N2 - This paper uses a novel GPS-coded dataset for more than three million car trips in the four largest German cities to measure the efficiency losses from using uniform fuel taxes as a second-best optimal tax to reduce traffic congestion. We estimate the short-run price elasticity of vehicle-kilometres travelled (VKT) across different hours of the day from a panel gravity equation. Identification of the price elasticity relies on comparing VKT changes between granular trip origin and destination pairs within each city. We find that the VKT price elasticity differs strongly across trips taken at different hours of the day, and that this elasticity correlates with contributions to the congestion externality. Using a policy simulation, we show that 52% of the deadweight loss of the congestion externality remains after levying a uniform fuel tax. KW - Congestion, externalities, traffic, optimal taxation Y1 - 2023 U6 - https://doi.org/10.2139/ssrn.4523285 PB - SSRN ER - TY - RPRT A1 - Levi, Sebastian A1 - Wolf, Ingo A1 - Flachsland, Christian A1 - Koch, Nicolas A1 - Koller, Florian A1 - Edmondson, Duncan T1 - Klimaschutz und Verkehr: Zielerreichung nur mit unbequemen Maßnahmen möglich. Ariadne-Analyse N2 - Die Klimaschutzziele für das Jahr 2030 sind im Verkehrssektor nur mit starken zusätzlichen Treibhausgasreduktionen erreichbar. Die beschlossenen Maßnahmen können laut gegenwärtigen Projektionen nur einen Bruchteil jener Emissionen reduzieren, welche für die Erreichung der Klimaschutzziele im Verkehrssektor notwendig wären. Um die politische Umsetzbarkeit zusätzlicher Klimaschutzmaßnahmen zu erörtern, analysieren wir die Emissionsminderungswirkung und die Bevölkerungsakzeptanz von 14 möglichen Maßnahmen, basierend auf Drittstudien und eigenen Erhebungen. Wir zeigen, dass die wirkungsstärksten Maßnahmen tendenziell eine geringe Zustimmung in der Bevölkerung erfahren, wobei die Lastenverteilung keinen sichtbaren Einfluss auf die Bevölkerungsakzeptanz hat. Maßnahmen, die in der Bevölkerung mehrheitlich unterstützt werden, führen nach gegenwärtigen Projektionen nur zu geringen Treibhausgasreduktionen, so dass die Erreichung der Klimaziele 2030 ohne kontroverse Maßnahmen wie höhere CO2-Preise oder einer flächendeckenden Maut unwahrscheinlich ist. Um die Befürwortung von gegenwärtig kontroversen Maßnahmen zu erhöhen, ist es notwendig, sichtbare Rückverteilungsmechanismen zu etablieren, Maßnahmen durch gruppenspezifische Kommunikation zu begleiten und die Einführung von Politikinstrumenten strategisch zu sequenzieren. KW - Centre for Sustainability Y1 - 2021 UR - https://ariadneprojekt.de/publikation/klimaschutz-und-verkehr-zielerreichung-nur-mit-unbequemen-massnahmen-moeglich/ ER - TY - JOUR A1 - Khanna, Tarun A1 - Baiocchi, Giovanni A1 - Callaghan, Max A1 - Creutzig, Felix A1 - Guias, Horia A1 - Haddaway, Neal R. A1 - Hirth, Lion A1 - Javaid, Aneeque A1 - Koch, Nicolas A1 - Laukemper, Sonja A1 - Löschel, Andreas A1 - del Mar Zamora Dominguez, Maria A1 - Minx, Jan C. T1 - A multi-country meta-analysis on the role of behavioural change in reducing energy consumption and CO2 emissions in residential buildings JF - Nature Energy N2 - Despite the importance of evaluating all mitigation options to inform policy decisions addressing climate change, a comprehensive analysis of household-scale interventions and their emissions reduction potential is missing. Here, we address this gap for interventions aimed at changing individual households’ use of existing equipment, such as monetary incentives or feedback. We have performed a machine learning-assisted systematic review and meta-analysis to comparatively assess the effectiveness of these interventions in reducing energy demand in residential buildings. We extracted 360 individual effect sizes from 122 studies representing trials in 25 countries. Our meta-regression confirms that both monetary and non-monetary interventions reduce the energy consumption of households, but monetary incentives, of the sizes reported in the literature, tend to show on average a more pronounced effect. Deploying the right combinations of interventions increases the overall effectiveness. We have estimated a global carbon emissions reduction potential of 0.35 GtCO2 yr−1, although deploying the most effective packages of interventions could result in greater reduction. While modest, this potential should be viewed in conjunction with the need for de-risking mitigation pathways with energy-demand reductions. Y1 - 2021 U6 - https://doi.org/10.1038/s41560-021-00866-x VL - 6 SP - 925 EP - 932 ER - TY - RPRT A1 - Edmondson, Duncan A1 - Flachsland, Christian A1 - aus dem Moore, Nils A1 - Koch, Nicolas A1 - Koller, Florian A1 - Gruhl, Henri A1 - Brehm, Johannes A1 - Levi, Sebastian T1 - Bewertung klimapolitischer Instrumentenmix-Pfade – Eine Anwendung auf leichte Nutzfahrzeuge in Deutschland Y1 - 2022 UR - https://ariadneprojekt.de/publikation/hintergrund-bewertung-klimapolitischer-instrumentenmix-pfade-eine-anwendung-auf-leichte-nutzfahrzeuge-in-deutschland/ PB - Kopernikus-Projekt Ariadne CY - Potsdam ER - TY - JOUR A1 - Edmondson, Duncan A1 - Flachsland, Christian A1 - aus dem Moore, Nils A1 - Koch, Nicolas A1 - Koller, Florian A1 - Gruhl, Henri A1 - Brehm, Johannes T1 - Anticipatory climate policy mix pathways: a framework for ex-ante construction and assessment applied to the road transport sector JF - Climate Policy Y1 - 2024 U6 - https://doi.org/10.1080/14693062.2024.2397440 SN - 1469-3062 ER - TY - JOUR A1 - Döbbeling-Hildebrandt, Niklas A1 - Miersch, Klaas A1 - Khanna, Tarun M. A1 - Bachelet, Marion A1 - Bruns, Stephan B. A1 - Callaghan, Max A1 - Edenhofer, Ottmar A1 - Flachsland, Christian A1 - Forster, Piers M. A1 - Kalkuhl, Matthias A1 - Koch, Nicolas A1 - Lamb, William F. A1 - Ohlendorf, Nils A1 - Steckel, Jan Christoph A1 - Minx, Jan C. T1 - Systematic review and meta-analysis of ex-post evaluations on the effectiveness of carbon pricing JF - Nature Communications N2 - Today, more than 70 carbon pricing schemes have been implemented around the globe, but their contributions to emissions reductions remains a subject of heated debate in science and policy. Here we assess the effectiveness of carbon pricing in reducing emissions using a rigorous, machine-learning assisted systematic review and meta-analysis. Based on 483 effect sizes extracted from 80 causal ex-post evaluations across 21 carbon pricing schemes, we find that introducing a carbon price has yielded immediate and substantial emission reductions for at least 17 of these policies, despite the low level of prices in most instances. Statistically significant emissions reductions range between –5% to –21% across the schemes (–4% to –15% after correcting for publication bias). Our study highlights critical evidence gaps with regard to dozens of unevaluated carbon pricing schemes and the price elasticity of emissions reductions. More rigorous synthesis of carbon pricing and other climate policies is required across a range of outcomes to advance our understanding of “what works” and accelerate learning on climate solutions in science and policy. Y1 - 2024 U6 - https://doi.org/10.1038/s41467-024-48512-w SN - 2041-1723 VL - 15 PB - Springer Science and Business Media LLC ER - TY - JOUR A1 - Amberg, Maximilian A1 - aus dem Moore, Nils A1 - Bekk, Anke A1 - Bergmann, Tobias A1 - Edenhofer, Ottmar A1 - Flachsland, Christian A1 - George, Jan A1 - Haywood, Luke A1 - Heinemann, Maik A1 - Held, Anne A1 - Kalkuhl, Matthias A1 - Kellner, Maximilian A1 - Koch, Nicolas A1 - Luderer, Gunnar A1 - Meyer, Henrika A1 - Nikodinoska, Dragana A1 - Pahle, Michael A1 - Roolfs, Christina A1 - Schill, Wolf-Peter T1 - Reformoptionen für ein nachhaltiges Steuer- und Abgabensystem. Wie Lenkungssteuern effektiv und gerecht für den Klima- und Umweltschutz ausgestaltet werden können JF - Perspektiven der Wirtschaftspolitik N2 - Steuern und Abgaben auf Produkte oder Verbrauch mit gesellschaftlichen Folgekosten (externe Kosten) – sogenannte Pigou- oder Lenkungssteuern – sind ein gesellschaftliches „Win-Win-Instrument“. Sie verbessern die Wohlfahrt und schützen gleichzeitig die Umwelt und das Klima. Dies wird erreicht, indem umweltschädigende Aktivitäten einen Preis bekommen, der möglichst exakt der Höhe des Schadens entspricht. Eine konsequente Bepreisung der externen Kosten nach diesem Prinzip könnte in Deutschland erhebliche zusätzliche Einnahmen erbringen: Basierend auf bisherigen Studien zu externen Kosten wären zusätzliche Einnahmen in der Größenordnung von 348 bis 564 Milliarden Euro pro Jahr (44 bis 71 Prozent der gesamten Steuereinnahmen) möglich. Die Autoren warnen allerdings, dass die Bezifferung der externen Kosten mit erheblichen Unsicherheiten verbunden ist. Damit Lenkungssteuern und -abgaben ihre positiven Lenkungs- und Wohlstandseffekte voll entfalten können, seien zudem institutionelle Reformen notwendig. Y1 - 2022 U6 - https://doi.org/10.1515/pwp-2021-0051 VL - 23 IS - 3 SP - 165 EP - 199 ER -