Adrien Vogt-Schilb

Marginal abatement cost curves and the optimal timing of mitigation measures

Decision makers facing abatement targets need to decide which abatement measures to implement, and in which order. Measure-explicit marginal abatement cost curves depict the cost and abating potential of available mitigation options. Using a simple intertemporal optimization model, we demonstrate why this information is not sufficient to design emission reduction strategies. Because the measures required to achieve ambitious emission reductions cannot be implemented overnight, the optimal strategy to reach a short-term target depends on longer-term targets. For instance, the best strategy to achieve Europeans -20% by 2020 target may be to implement some expensive, high-potential, and long-to-implement options required to meet the -75% by 2050 target. Using just the cheapest abatement options to reach the 2020 target can create a carbon-intensive lock-in and make the 2050 target too expensive to reach. Designing mitigation policies requires information on the speed at which various measures to curb greenhouse gas emissions can be implemented, in addition to the information on the costs and potential of such measures provided by marginal abatement cost curves.

Decarbonizing development: three steps to a zero-carbon future

This report lays out three steps for a smooth transition to a zero-carbon future and provides data, examples and policy advice to help countries makes the shift. Overview Getting to zero net emissions and stabilizing climate change starts with planning for the long-term future and not stopping at short-term goals. It means getting prices right as part of a broad policy package that can trigger changes in both investments and behaviors, and it requires smoothing the transition for those most affected. A new World Bank report walks policymakers through those three steps with data, examples and policy advice to help put countries on a path to decarbonizing their development in a smooth and orderly way. The solutions exist, and they are affordable – if governments take action today, the report says.

Unbreakable : building the resilience of the poor in the face of natural disasters

Economic losses from natural disasters totaled 92 billion dollars in 2015. Such statements, all too commonplace, assess the severity of disasters by no other measure than the damage inflicted on buildings, infrastructure, and agricultural production. But 1 dollars in losses does not mean the same thing to a rich person that it does to a poor person; the gravity of a

Transition to Clean Capital, Irreversible Investment and Stranded Assets

92 billion loss depends on who experiences it. By focusing on aggregate losses—the traditional approach todisaster risk—we restrict our consideration to how disasters affect those wealthy enough to have assets to lose in the first place, and largely ignore the plight of poor people.This report moves beyond asset and production losses and shifts its attention to how natural disasters affect people’s well-being. Disasters are far greater threats to well-being than traditional estimates suggest. This approach provides a more nuanced view of natural disasters than usual reporting, and a perspective that takes fuller account of poor people’s vulnerabilities. Poor people suffer only a fraction of economic losses caused by disasters, but they bear the brunt of their consequences. Understanding the disproportionate vulnerability of poor people also makes the case for setting new intervention priorities to lessen the impact of natural disasters on the world’s poor, such as expanding financial inclusion, disaster risk and health insurance, social protection and adaptive safety nets, contingent finance and reserve funds, and universal access to early warning systems.Efforts to reduce disaster risk and poverty go hand in hand. Because disasters impoverish so many, disaster risk management is inseparable from poverty reduction policy, and vice versa. As climate change magnifies natural hazards, and because protection infrastructure alone cannot eliminate risk, a more resilient population has never been more critical to breaking the cycle of disaster-induced poverty.

Climate Change and Poverty -- an Analytical Framework

This paper uses a Ramsey model with two types of capital to analyze the optimal transition to clean capital when polluting investment is irreversible. The cost of climate mitigation decomposes as a technical cost of using clean instead of polluting capital and a transition cost from the irreversibility of pre-existing polluting capital. With a carbon price, the transition cost can be limited by underutilizing polluting capital, at the expense of a loss in the value of polluting assets (stranded assets) and a drop in income. In contrast, policy instruments that focus on redirecting investments -- such as feebates or environmental standards -- prevent underutilization of existing capital, avoid stranded assets, and reduce short-term losses; but they reduce emissions more slowly and increase the intertemporal cost of the transition. The paper investigates inter- and intra-generational distributional impacts and the political acceptability of climate change mitigation policy instruments.

How Capital-Based Instruments Facilitate the Transition Toward a Low-Carbon Economy: A Tradeoff between Optimality and Acceptability

Climate change and climate policies will affect poverty reduction efforts through direct and immediate impacts on the poor and by affecting factors that condition poverty reduction, such as economic growth. This paper explores this relation between climate change and policies and poverty outcomes by examining three questions: the (static) impact on poor peoples livelihood and well-being; the impact on the risk for non-poor individuals to fall into poverty; and the impact on the ability of poor people to escape poverty. The paper proposes four channels that determine household consumption and through which households may escape or fall into poverty (prices, assets, productivity, and opportunities). It then discusses whether and how these channels are affected by climate change and climate policies, focusing on the exposure, vulnerability, and ability to adapt of the poor (and those vulnerable to poverty). It reviews the existing literature and offers three major conclusions. First, climate change is likely to represent a major obstacle to a sustained eradication of poverty. Second, climate policies are compatible with poverty reduction provided that (i) poverty concerns are carefully taken into account in their design and (ii) they are accompanied by the appropriate set of social policies. Third, climate change does not modify how poverty policies should be designed, but it creates greater needs and more urgency. The scale issue is explained by the fact that climate will cause more frequent and more severe shocks; the urgency, by the need to exploit the window of opportunity given to us before climate impacts are likely to substantially increase.

Marginal abatement cost curves and the quality of emission reductions: a case study on Brazil

This paper compares the temporal profile of efforts to curb greenhouse gas emissions induced by two mitigation strategies: a regulation of all emissions with a carbon price and a regulation of emissions embedded in new capital only, using capital-based instruments such as investment regulation, differentiation of capital costs, or a carbon tax with temporary subsidies on brown capital. A Ramsey model is built with two types of capital: brown capital that produces a negative externality and green capital that does not. Abatement is obtained through structural change (green capital accumulation) and possibly through under-utilization of brown capital. Capital-based instruments and the carbon price lead to the same long-term balanced growth path, but they differ during the transition phase. The carbon price maximizes social welfare but may cause temporary under-utilization of brown capital, hurting the owners of brown capital and the workers who depend on it. Capital-based instruments cause larger intertemporal welfare loss, but they maintain the full utilization of brown capital, smooth efforts over time, and cause lower immediate utility loss. Green industrial policies including such capital-based instruments may thus be used to increase the political acceptability of a carbon price. More generally, the carbon price informs on the policy effect on intertemporal welfare but is not a good indicator to estimate the impact of the policy on instantaneous output, consumption, and utility.

Would Climate Policy Improve The European Energy Security

Decision makers facing emission-reduction targets need to decide which abatement measures to implement, and in which order. This article investigates how marginal abatement cost (MAC) curves can inform such a decision. We re-analyse a MAC curve built for Brazil by 2030, and show that misinterpreting MAC curves as abatement supply curves can lead to suboptimal strategies. It would lead to (1) under-investment in expensive, long-to-implement and large-potential options, such as clean transportation infrastructure, and (2) over-investment in cheap but limited-potential options such as energy-efficiency improvement in refineries. To mitigate this issue, the article proposes a new graphical representation of MAC curves that explicitly renders the time required to implement each measure. Policy relevance In addition to the cost and potential of available options, designing optimal short-term policies requires information on long-term targets (e.g. halving emissions by 2050) and on the speed at which measures can deliver emission reductions. Mitigation policies are thus best investigated in a dynamic framework, building on sector-scale pathways to long-term targets. Climate policies should seek both quantity and quality of abatement, by combining two approaches: a ‘synergy approach’ that focuses on the cheapest mitigation options and maximizes co-benefits, and an ‘urgency approach’ that starts from a long-term objective and works backward to identify actions that need to be implemented early. Accordingly, sector-specific policies may be used (1) to remove implementation barriers on negative- and low-cost options and (2) to ensure short-term targets are met with abatement of sufficient quality. Indeed, such policies can avoid under-investment in the long-to-implement options required to reach long-term targets, which are otherwise difficult to enforce.

Long-Term Mitigation Strategies and Marginal Abatement Cost Curves: A Case Study on Brazil

Energy security improvement is often presented as a co-benefit of climate policies. This paper evaluates this claim. It investigates whether climate policy would improve energy security, while accounting for the difficulties entailed by the many-faceted nature of the concept and the large uncertainties on the determinants of future energy systems. A multi-dimension analysis grid is used to capture the energy security concept, and a database of scenarios allows us to explore the uncertainty space. The results, focusing on Europe, reveal there is no unequivocal effect of climate policy on all the perspectives of energy security. Moreover, time significantly matters: the impact of climate policies is mixed in the short term and globally good in the medium term. In the long term, there is a risk of degradation of the energy security. Lastly, we examine the robustness of our results to uncertainties on drivers of economic growth, availability of fossil fuels and the potentials and low-carbon technologies, and find that they are sensitive mainly to fossil fuels availability, low carbon technologies in the energy sector and improvements in energy efficiency.

Optimal transition from coal to gas and renewable power under capacity constraints and adjustment costs

Decision makers facing abatement targets need to decide which abatement measures to implement, and in which order. This paper investigates the ability of marginal abatement cost (MAC) curves to inform this decision, reanalysing a MAC curve developed by the World Bank on Brazil. Misinterpreting MAC curves and focusing on short-term targets (e.g., for 2020) would lead to under-invest in expensive, long-to-implement and large-potential options, such as clean transportation infrastructure. Meeting short-term targets with marginal energy-efficiency improvements would lead to carbon-intensive lock-ins that make longer-term targets (e.g., for 2030 and beyond) impossible or too expensive to reach. Improvements to existing MAC curves are proposed, based on (1) enhanced data collection and reporting; (2) a simple optimization tool that accounts for constraints on implementation speeds; and (3) new graphical representations of MAC curves. Designing climate mitigation policies can be done through a pragmatic combination of two approaches. The synergy approach is based on MAC curves to identify the cheapest mitigation options and maximize co-benefits. The urgency approach considers the long-term objective (e.g., halving emissions by 2050) and works backward to identify actions that need to be implemented early, such as public support to clean infrastructure and zero-carbon technologies.