Optimal policy instruments for externality-producing durable goods under present bias

When consumers exhibit present bias, the standard solution to market failures caused by externalities—Pigouvian pricing—is suboptimal. I investigate policies aimed at externalities for present-biased consumers. Optimal policy includes an instrument to correct the externality and an instrument to correct the present bias. Either instrument can be an incentive-based policy (e.g. a tax on fuel economy) or a command-and-control policy (e.g. a fuel economy mandate). Under consumer heterogeneity, a command-and-control policy may dominate an incentive-based policy. Calibrated to the US automobile market, simulation results suggest that the second-best gasoline tax is 3–30% higher than marginal external damages. The optimal price policy includes a gasoline tax set about equal to marginal external damages and a fuel economy tax that increases the price of an average non-hybrid car by about $550–$2200 relative to the price of an average hybrid car.     

Carbon abatement in the fuel market with biofuels: Implications for second best policies

A carbon tax on fuel would penalize carbon intensive fuels like gasoline and shift fuel consumption to less carbon intensive alternatives like biofuels. Since biofuel production competes for land with agricultural production, a carbon tax could increase land rents and raise food prices. This paper analyzes the welfare effect of a carbon tax on fuel consisting of gasoline and biofuel in the presence of a labor tax, with and without a biofuel subsidy. The market impacts of a carbon tax are also compared with that of a subsidy. Findings show that if a carbon tax increases biofuel demand, the tax interaction effect due to higher fuel prices is exacerbated by higher land rent and food prices and greater erosion of the carbon tax base. Thus, the second best optimal carbon tax for fuel is lower with biofuel in the fuel mix, especially if biofuel is subsidized.     

Alternative transportation fuel standards: Welfare effects and climate benefits

This paper develops an integrated model of the fuel and agricultural sectors to analyze the welfare and greenhouse gas emission (GHG) effects of the existing Renewable Fuel Standard (RFS), a Low Carbon Fuel Standard (LCFS) and a carbon price policy. The conceptual framework shows that these policies differ in the incentives they create for the consumption and mix of different types of biofuels and in their effects on food and fuel prices and GHG emissions. We also simulate the welfare and GHG effects of these three policies which are normalized to achieve the same level of US GHG emissions. By promoting greater production of food-crop based biofuels, the RFS is found to lead to a larger reduction in fossil fuel use but also a larger increase in food prices and a smaller reduction in global GHG emissions compared to the LCFS and carbon tax. All three policies increase US social welfare compared to a no-biofuel baseline scenario due to improved terms-of-trade, even when environmental benefits are excluded; global social welfare increases with a carbon tax but decreases with the RFS and LCFS due to the efficiency costs imposed by these policies, even after including the benefits of mitigating GHG emissions.     

Environmental policy and macroeconomic dynamics in a new Keynesian model

This paper studies the dynamic behavior of an economy under different environmental policy regimes in a New Keynesian model with nominal and real uncertainty. We find the following results: (i) an emissions cap policy is likely to dampen macroeconomic fluctuations; (ii) staggered price adjustment alters significantly the performance of the environmental policy regime put in place; (iii) the optimal environmental policy response to shocks is strongly influenced by the degree to which prices adjust and by the monetary policy reaction.     

Salience of carbon taxes in the gasoline market

We demonstrate that the carbon tax imposed by the Canadian province of British Columbia caused a decline in short-run gasoline demand that is significantly greater than would be expected from an equivalent increase in the market price of gasoline. That the carbon tax is more salient, or yields a larger change in demand than equivalent market price movements, is robust to a range of specifications. As a result of the large consumer response to the tax, we calculate that during its first four years, the tax reduced carbon dioxide emissions from gasoline consumption by 2.4 million tonnes.     

Incentives and prices in an emissions trading scheme with updating

Emissions trading schemes where allocations are based on updated baseline emissions give firms less incentive to reduce emissions for a given quota (or allowance) price. Nevertheless, according to Böhringer and Lange [On the design of optimal grandfathering schemes for emission allowances, Europ. Econ. Rev. 49 (2005) 2041–2055], such allocation schemes are cost-effective if the system is closed and allocation rules are identical across firms. In this paper, we show that the cost-effective solution may be infeasible if marginal abatement costs grow too fast. Moreover, if a price cap or banking/borrowing is introduced, the abatement profile is no longer the same as in the case with an auction (or lump-sum allocation). In addition, we show that with allocation based on updated emissions, the quota price will always exceed marginal abatement costs, possibly misguiding policy makers and investors about abatement costs. Numerical simulations indicate that the quota price most likely will be several times higher than marginal abatement costs, unless a significant share of allowances is auctioned.     

Announcing climate policy: Can a green paradox arise without scarcity?

Unintended consequences of a pre-announced climate policy are studied within a framework that allows for competition between polluting and clean energy sources. We show that early announcement of a carbon tax gives rise to a “green-paradox,” in that it increases emissions in the interim period (between announcement and actual implementation), irrespective of the scarcity of fossil fuels. The paradoxical outcome is driven by consumption-saving tradeoffs facing households who seek to smooth consumption over time and holds both when the announced implementation date is taken as a credible threat and when households are skeptical about the (political) will or capability of the government to implement the policy as announced.     

Cost-effective environmental policy: implications of induced technological change

Cost-effective environmental policy generally requires that all emission sources are faced with the same tax. In this paper I discuss how the existence of induced technological change may alter this result, if at least some of the effect is external to the firm. Focusing on Learning by doing (LBD) effects in abatement activities, it is shown that emission sources with external learning effects should be faced with a higher tax than emission sources with only autonomous technological change. By using simple numerical simulations, it is further investigated to what degree a cost-effective climate policy differs from a free quota market, under various assumptions about learning effects, diffusion of technology and environmental targets. The results indicate that optimal taxes may be significantly higher in the industrial world than in the developing world. Moreover, the industrial world's share of global abatement may be much higher in a cost-effective solution than in a free quota market. The global cost savings of a fully flexible implementation of the Kyoto Protocol are further questioned, as potential spillover effects of technological growth in the industrial world are not internalised in the market.     

Oil Exploration under Climate Treaties

In this paper we focus on how an international climate treaty will influence the exploration of oil in non-OPEC countries. We present a numerical intertemporal global equilibrium model for the fossil fuel markets. The international oil market is modelled with a cartel (OPEC) and a competitive fringe on the supply side, following a Nash–Cournot approach. An initial resource base for oil is given in the non-OPEC region. However, the resource base changes over time due to depletion, exploration, and discovery. When studying the effects of different climate treaties on oil exploration, two contrasting incentives apply. If an international carbon tax is introduced, the producer price of oil will drop compared to the reference case. This gives an incentive to reduce oil production and exploration. However, the oil price may increase less rapidly over time, which gives an incentive to expedite production and exploration. In fact, in the case of a rising carbon tax we find the last incentive to be the strongest, which means that an international climate treaty may increase oil exploration in non-OPEC countries for the coming decades and reduce OPEC's market share.     

Emissions cap or emissions tax? A multi-sector business cycle analysis

We develop a multi-sector business cycle model to analyze stochastic implications of reducing CO₂ emissions with carbon permits or with carbon taxes in the presence of multiple sources of macroeconomic uncertainty. The model is calibrated to reflect the U.S. experience. As in previous studies, using a single-sector version of our model, we find that the cap regime generates lower volatility of real variables than the tax regime, but the latter may be preferable from the welfare perspective. Still, our multi-sector analysis points to the importance of the origin of the shocks in the ranking of the two instruments and to the desirability of going beyond a single-sector analysis in evaluating their merits. We find no significant difference between the cap and the tax regimes when shocks come from non-energy sectors. In contrast, the cap has lower volatility but higher welfare costs than the tax for the shocks to energy production.     

Prices vs quantities with multiple pollutants

We examine the choice of policy instruments (price, quantity or a mix of the two) when two pollutants are regulated and firms' abatement costs are private information. Whether abatement efforts are complements or substitutes is key determining the choice of policies. When pollutants are complements, a mixed policy instrument with a tax on one pollutant and a quota on another is sometimes preferable even if the pollutants are identical in terms of benefits and costs of abatement. Yet, if they are substitutes, the mixed policy is dominated by taxes or quotas.     

The Weitzman price corner

The standard theoretical approach to comparing price and quantity policies is strictly interior. We extend the comparison to account for the possibility of corner outcomes, where a polluting industry responds to a tax by abating either completely or not at all. We show that, when the uncertainty in marginal costs is high, the inclusion of corner outcomes confers an extra and unnoticed advantage upon an emissions tax. In situations where the standard approach would recommend a quantity policy, the possibility of corners can reverse that recommendation.     

Cumulative carbon emissions and economic policy: In search of general principles

We exploit recent advances in climate science to develop a physically consistent, yet surprisingly simple, model of climate policy. It seems that key economic models have greatly overestimated the delay between carbon emissions and warming, and ignored the saturation of carbon sinks that takes place when the atmospheric concentration of carbon dioxide rises. This has important implications for climate policy. If carbon emissions are abated, damages are avoided almost immediately. Therefore it is optimal to reduce emissions significantly in the near term and bring about a slow transition to optimal peak warming, even if optimal steady-state/peak warming is high. The optimal carbon price should start relatively high and grow relatively fast.     

Strategic environmental policy; eco-dumping or a green strategy?

The Porter hypothesis claims that a strong environmental policy best serves the interests of a nation's export industry. While this hypothesis seems to be based on some form of bounded rationality, this paper argues that governments may have good reasons for setting an especially strong environmental policy even though firms are fully rational. If the available abatement technology turns the environment into an “inferior input”, competitiveness is spurred by a strong environmental policy. The government should take advantage of this, and set an especially strict emission quota or an especially high emission tax. The findings in the paper also has consequences for the desirability of international cooperation with respect to national environmental policy. If a strict environmental policy spurs competitiveness, the environment is better protected without cooperation.     

Environmental policy à la carte: Letting firms choose their regulation

Under uncertainty, the optimal choice between price and quantity instruments depends on the technology of the regulated firms, which is often private information. We consider an environmental policy that delegates the prices-versus-quantities decision to the firms by offering them the choice between an emissions tax and permit trading. Such an approach is currently used in Swiss climate policy. We provide a detailed characterization of the optimal policy and show that this approach reduces expected social costs compared to a pure tax or permit-trading regime. We demonstrate that an optimal allocation of firms to instruments can be achieved despite substantial informational constraints, and that all firms gain from the introduction of the instrument choice compared to optimally designed single-instrument policies. Furthermore, we discuss the conditions under which this approach is likely to be preferable to a hybrid regulation.     

Incomplete International Cooperation to Reduce CO2 Emissions: The Case of Price Discrimination

This paper analyzes the effect of introducing a fuel tax in some countries, but not all, when the world fuel market is monopolistic. Based on the observation that price discrimination becomes possible in these circumstances, it is shown that the fuel price in countries not levying the tax may increase, in contrast to common views.     

Market equilibrium and welfare effects of a fuel tax in China: The impact of consumers' response through driving patterns

We investigate the market equilibrium and welfare effects of a fuel tax in China relative to an alternative policy instrument that rations the number of new automobile sales through auctioned quotas. Unlike those of previous studies, our modeling approach incorporates both household car purchase and utilization decisions, the latter of which have been ignored in previous studies on China's fuel tax. Ignoring this margin of choice will underestimate the fuel tax's ability to mitigate externalities. Using detailed household-level panel data and a fixed effects econometric specification, we estimate the fuel price elasticity of vehicle miles traveled is −0.59 on average. The results of the counterfactual analysis suggest that a 51% increase in tax-inclusive gasoline prices will reduce car sales by 24.9% but increase social welfare to a degree that depends on vehicles' lifetime. We find that compared to auctioned quotas, the fuel tax results in greater car sales but higher social welfare.     

Is there really a green paradox?

In the absence of a CO₂ tax, the anticipation of a cheaper renewable backstop increases current emissions of CO₂. Since the date at which renewables are phased in is brought forward and more generally future emissions of CO₂ will decrease, the effect on global warming is unclear. Green welfare falls if the backstop is relatively expensive and full exhaustion of fossil fuels is optimal, but may increase if the backstop is sufficiently cheap relative to the cost of extracting the last drop of fossil fuels plus marginal global warming damages as then it is attractive to leave more fossil fuels unexploited and thus limit CO₂ emissions. We establish these results by analyzing depletion of non-renewable fossil fuels followed by a switch to a clean renewable backstop, paying attention to timing of the switch and the amount of fossil fuels remaining unexploited. We also discuss the potential for limit pricing when the non-renewable resource is owned by a monopolist. Finally, we show that if backstops are already used and more backstops become economically viable as the price of fossil fuels rises, a lower cost of the backstop will either postpone fossil fuel exhaustion or leave more fossil fuel in situ, thus boosting green welfare. However, if a market economy does not internalize global warming externalities and renewables have not kicked in yet, full exhaustion of fossil fuel will occur in finite time and a backstop subsidy always curbs green welfare.     

Jobs and climate policy: Evidence from British Columbia's revenue-neutral carbon tax

This paper examines the employment impact of British Columbia's revenue-neutral carbon tax implemented in 2008. While all industries appear to benefit from the redistributed tax revenues, the most carbon-intensive and trade-sensitive industries see employment fall with the tax, while clean service industries see employment rise. By aggregating across industries I find the BC carbon tax generated, on average, a small but statistically significant 0.74 percent annual increases in employment over the 2007–2013 period. This paper provides initial evidence showing how a revenue-neutral carbon tax may not adversely affect employment.     

Optimal abatement of carbon emission flows

We study optimal carbon capture and storage (CCS) from point sources, taking into account damages incurred from the accumulation of carbon in the atmosphere and exhaustibility of fossil fuel reserves. High carbon concentrations call for full CCS, meaning zero net emissions. We identify conditions under which partial or no CCS is optimal. In the absence of CCS the CO2 stock might be inverted U-shaped. With CCS more complicated behavior may arise. It can be optimal to have full capture initially, yielding a decreasing stock, then partial capture while keeping the CO2 stock constant, and a final phase without capture but with an inverted U-shaped CO2 stock. We also introduce the option of adaptation and provide a unified theory regarding the optimal use of CCS and adaptation.