Prices vs. Quantities and the Intertemporal Dynamics of the Climate Rent

This paper provides a formal survey of price and quantity instruments for mitigating global warming. We explicitly consider policies’ impact on the incentives of resource owners who maximize their profits intertemporally. We focus on the informational and commitment requirements of the regulator. Furthermore, we study the interplay between (private) resource extraction rent and (public) climate rent and ask how property and management of the climate rent can be assigned between regulator and resource sector. There are only two instruments that unburden the regulator from the complex intertemporal management of the climate rent and associated commitment problems: in the cost-benefit world, we derive a stock-dependent tax rule; in the cost-effective (carbon budget) world, only an emissions trading scheme with free banking and borrowing can shift intertemporal timing decisions completely to the market.resource extraction, climate rent, intertemporal policy instruments, prices vs. quantities, Hotelling

Adapt, Mitigate, or Die? The Fallacy of a False Trade-off by Ottmar Edenhofer and Steffen Brunner

Klimaveränderung; Internationale Umweltpolitik; Welt

Mitigation Strategies and Costs of Climate Protection: The effects of ETC in the hybrid Model MIND

MIND is a hybrid model incorporating several energy related sectors in an endogenous growth model of the world economy. This model structure allows a better understanding of the linkages between the energy sectors and the macro-economic environment. We perform a sensitivity analysis and parameter studies to improve the understanding of the economic mechanisms underlying opportunity costs and the optimal mix of mitigation options. Parameters representing technological change that permeates the entire economy have a strong impact on both the opportunity costs of climate protection and on the optimal mitigation strategies, e.g. parameters in the macro-economic environment and in the extraction sector. Sector-specific energy technology parameters change the portfolio of mitigation options but have only modest effects on opportunity costs, e.g. learning rate of the renewable energy technologies. We conclude that feedback loops between the macro-economy and the energy sectors are crucial for the determination of opportunity costs and mitigation strategies.Endogenous technological change, Climate change mitigation costs, Integrated assessment, Growth model, Energy sector, Integrated assessment

Learning or Lock-in: Optimal Technology Policies to Support Mitigation

We investigate conditions that aggravate market failures in energy innovations, and suggest optimal policy instruments to address them. Using an intertemporal general equilibrium model we show that “small” market imperfections may trigger a several decades lasting dominance of an incumbent energy technology over a dynamically more efficient competitor, given that the technologies are very good substitutes. Such a “lock-in” into an inferior technology causes significantly higher welfare losses than market failure alone, notably under ambitious mitigation targets. More than other innovative industries, energy markets are prone to these lock-ins because electricity from different technologies is an almost perfect substitute. To guide government intervention, we compare welfare-maximizing technology policies in addition to carbon pricing with regard to their efficiency, effectivity, and robustness. Technology quotas and feed-in-tariffs turn out to be only insignificantly less efficient than first-best subsidies and seem to be more robust against small perturbations.renewable energy subsidy, renewable portfolio standard, feed-in-tariffs, carbon pricing

Avoiding Carbon Lock-In: Policy Options for Advancing Structural Change

A major obstacle for the transformation to a low-carbon economy is the risk of a carbon lock-in: fossil fuel-based ('dirty') technologies dominate the market although their carbon-free ('clean') alternatives are dynamically more efficient. We study the interaction of learning-by-doing spillovers and the substitution elasticity between the clean and the dirty sector in an intertemporal general equilibrium model. We find that the substitution possibilities between the two sectors have an ambivalent effect: although a high substitution elasticity requires less aggressive mitigation policies than a low one, it creates a greater lock-in in the absence of regulation. The optimal policy response consists of a permanent carbon tax as well as a learning subsidy for clean technologies. A single policy instrument can also avoid high welfare losses, but a more stringent mitigation target can only be achieved at painful costs. We demonstrate that the policy implication of [Acemoglu et al. 2012] is limited in scope. Our numerical results also highlight that infrastructure provision is crucial to facilitate the low-carbon transformation.structural change, low-carbon economy, carbon lock-in, mitigation policies, learning-by-doing

Renewable Energy Subsidies: Second-Best Policy or Fatal Aberration for Mitigation?

This paper evaluates the consequences of renewable energy policies on welfare, resource rents and energy costs in a world where carbon pricing is imperfect and the regulator seeks to limit emissions to a (cumulative) target. We use a global general equilibrium model with an intertemporal fossil resource sector. We calculate the optimal second-best renewable energy subsidy and compare the resulting welfare level with an efficient first-best carbon pricing policy. If carbon pricing is permanently missing, mitigation costs increase by a multiple (compared to the optimal carbon pricing policy) for a wide range of parameters describing extraction costs, renewable energy costs, substitution possibilities and normative attitudes. Furthermore, we show that small deviations from the second-best subsidy can lead to strong increases in emissions and consumption losses. This confirms the rising concerns about the occurrence of unintended side effects of climate policy { a new version of the green paradox. We extend our second-best analysis by considering two further types of policy instruments: (1) temporary subsidies that are displaced by carbon pricing in the long run and (2) revenue-neutral instruments like a carbon trust and a feed-in-tariff scheme. Although these instruments cause small welfare losses, they have the potential to ease distributional conflicts as they lead to lower energy prices and higher fossil resource rents than the optimal carbon pricing policy.Feed-in-Tariff, Carbon Trust, Carbon Pricing, Supply-Side Dynamics, Green Paradox, Climate Policy

CCS-Bonds as a superior instrument to incentivize secure carbon sequestration

Geological sequestration of CO2 on a massive scale implies that large area fractions of the underground could become flooded by CO2, imposing a unprecedented regulatory challenge to environmental authorities. Therefore we propose carbon sequestration bonds as complementary, market-based instruments that should further help to manage the risk of decadal-scale CO2 leakage. Such bond schemes address market failures that could occur if the investment behavior of operators under uncertainty differed from society’s preference. For a stylized setup we demonstrate that our bond system has the potential to simultaneously address regulatory challenges stemming from information asymmetries and diverging orders of preference

Planet-proofing the global food system

Without a great food system transformation, the world will fail to deliver both on the United Nations Sustainable Development Goals and the Paris Climate Agreement. There are five grand challenges to be faced, by science and society, to effect that transformation

The strategic dimension of financing global public goods

One challenge in addressing transboundary problems such as climate change is the incentive to free-ride. Transfers from multilateral compensation funds are often used to counteract such incentives, albeit with varying success. We examine how such funds can change the incentive to free-ride in a global public-goods game. In our game, self-interested countries choose their own preferred course, deciding their voluntary public good provision, whether to join a fund that offers compensation for providing the public good and the volume of compensatory payments. We show that (i) total public-good provision is higher when those contributing are given more compensation; and (ii) non-participation in the fund can be punished if the remaining members decrease their public-good provision sufficiently. We then examine three specific fund designs. In the first, the compensation paid to each country is equal to the percentage of above-average total costs for public-goods provision. This design is best able to deter free-riding and can establish the social optimum as the equilibrium. In the second, the compensation paid to each country is a function of the marginal cost of their public-good provision. Here there are significant incentives to free-ride. In the third case, the monetary resources provided by the fund are fixed, a design frequently encountered in international funds. This design is the one least able to deter free-riding. © 2020 The Author(s

Climate policies for road transport revisited (II): Closing the policy gap with cap-and-trade

Current policies in the road transport sector fail to deliver consistent and efficient incentives for greenhouse gas abatement (see companion article by Creutzig et al., 2010a). Market-based instruments such as cap-and-trade systems close this policy gap and are complementary to traditional policies which are required where specific market failures arise. Even in presence of strong existing non-market policies, cap-and-trade delivers additional abatement and efficiency by incentivizing demand side abatement options. This paper analyzes generic design options and economic impacts of including the European road transport sector to the EU ETS. The point of regulation in a road transport cap-and-trade system should be upstream in the fuel chain to ensure effectiveness (cover all life-cycle emissions and avoid double-counting), efficiency (incentivize all abatement options) and low transaction costs. Based on year 2020 marginal abatement cost curves from different models and current EU climate policy objectives we show that in contrast to conventional wisdom road transport inclusion would not change the EU ETS allowance price. This puts concerns over industrial carbon leakage as a consequence of adding road transport to the EU ETS into perspective.Climate Policy, Road Transport, Cap-and-trade