Biofuels and Climate Change Mitigation: A CGE Analysis Incorporating Land-Use Change

We examine the impact of a “green network effect” in a market characterized by consumers’ environmental awareness and competition between firms in terms of both environmental quality and product prices. The unique aspect of this model comes from the assumption that an increase in the number of consumers of green (brown) product increases the satisfaction of each green (brown) consumer. We show that, paradoxically, when the network effect of a green product is higher than that of a brown product, this externality reduces product environmental quality and raises consumption of the green product. Conversely, when the network effect of the brown product is higher, the externality improves product environmental quality and raises consumption of the brown product. In both cases, the network effect does not affect the overall pollution level. The externality correction requires the use of three optimal fiscal policies: an ad valorem tax on products, an emission tax, and a subsidy or a tax on the green purchase. A second-best optimum can also be reached through the green taxation.     

Emission tax and optimal privatization in Cournot–Bertrand comparison

We compare a Cournot with a Bertrand duopoly in a differentiated mixed market when both emission tax and privatization policies are used together. We find that the optimal emission tax is always lower than the marginal environmental damage, and it is always lower under Cournot than under Bertrand. We also find that the optimal privatization is always a partial privatization, and it is always higher under Cournot than under Bertrand. The socially optimal combinations of emission tax and privatization will damage the environment most, but Cournot yields lower environmental damage and social welfare than those under Bertrand. Finally, we show that the environmental damage is non-monotone in the level of privatization under both Cournot and Bertrand competitions.     

Optimal Emissions Taxation under Imperfect Competition in a Durable Good Industry

This paper investigates optimal emissions taxation under imperfect competition in a durable good industry where products are sold (instead of rented). As a benchmark, attention is paid to the special case of monopoly with exogenously given product durability. In line with previous literature, the optimal emission tax in this benchmark model falls short of marginal damage (underinternalization). Extending the benchmark model either to the case of an oligopolistic market structure and/or to the case of endogenous product durability then provides two cases in which the optimal emission tax overinternalizes marginal damage.     

Optimal Tax Policy under Environmental Quality Competition

This paper studies the socially optimal emission and commodity tax policy when consumers are willing to pay a price-premium for environmentally friendlier variants of a commodity vertically differentiated in environmental quality. The first-best levels of quality can be obtained by a combination of a uniform ad valorem tax and an emission tax (or a subsidy for buying green products). The first-best emission tax is higher than the social valuation of the positive externality associated with average environmental quality. Regardless of environmentally conscious consumers, if only one instrument is available, the second-best emission tax is equal to the social valuation of the positive externality associated with average environmental quality. A uniform ad valorem tax increases welfare only if the social valuation of the positive externality associated with average environmental quality is low enough.     

Optimal combination of innovation and environmental policies under technology licensing

Under what conditions will a carbon tax encourage environmental innovation? Can a regulator design an optimal environmental policy to reduce emissions and to promote clean technologies? This paper studies optimal environmental policy in the situation where a monopoly innovator develops and licenses clean production technologies to downstream polluting firms. We find that (i) a higher emission tax will encourage innovation when the burden of the tax payment in the polluters' costs and/or the price-elasticity of the demand for polluting goods are small, (ii) the innovation-inducing effects of emission tax are inversely related to the emission-reduction (Pigouvian) effects of the tax, and (iii) the social optimum can be achieved by the mix of tax and subsidy. We also show that if the policy instrument is limited to the tax, the second-best tax rate would lie between the marginal damage and the first-best rate. By performing numerical simulations, we also demonstrate that the optimal mix of the emission tax and R&D subsidy can have “double dividend” benefits.     

Strategic Voting for Noncooperative Environmental Policies in Open Economies

In this paper, we construct a political-economy model of strategic environmental policymaking with different degrees of product differentiation and different market structures, and examine how strategic voting decisions are affected by the choice of environmental policy instruments (tax or standard). We show that in a Cournot market structure, voters elect tax-setting policymakers who are more green than themselves when product differentiation and/or environmental externalities are more prominent. In a Bertrand market structure, they elect more green tax-setting policymakers than themselves. On the other hand, they elect standard-setting policymakers who are less green than themselves. The results confirm the advantage of the overall use of emission tax over that of emission standard regarding the welfare effect of strategic voting.     

Does a Recession Call for Less Stringent Environmental Policy? A Partial-Equilibrium Second-Best Analysis

This paper analyses second-best optimal environmental policy responses to real and financial shocks in a two-period partial equilibrium model with heterogeneous firms, an environmental externality, and credit constraints. We show that, to alleviate credit constraints and encourage investment, the second-best optimal emission tax falls short of marginal emission damages. The optimal response to shocks depends on how the shock affects the size of the environmental and credit market failures and the effectiveness of the tax in alleviating these market failures. Under mildly restrictive assumptions on functional forms, the optimal response to a (persistent) negative productivity shock or a tightening of credit is to reduce the emission tax. Our results are informative for how climate change policy should optimally change with the business cycle.     

Environmental taxation and mergers in oligopoly markets with product differentiation

We analyze the effect of mergers on optimal environmental taxation in a Cournot oligopoly market with product differentiation. Our result indicates that the adjustment in emission tax crucially depends on the post-merger output distortion and pollution intensities. Specifically, we find that the optimal emission tax increases post-merger as long as pollution intensity of firms is higher and output distortion smaller post-merger than pre-merger. Furthermore, our result suggests that there is no need to revise environmental policy in markets where pollution intensity of firms does not change post-merger and (i) products are completely differentiated, or (ii) there are many firms for any degree of product differentiation.     

Tax Competition in Vertically Differentiated Markets with Environmentally Conscious Consumers

This paper analyses the effects of tax competition on environmental product quality, pollution and welfare in a two-country, vertically differentiated, international duopoly, in which consumers are environmentally conscious. The firm in each country chooses first the environmental quality of its product (which reflects the emissions generated in the production process) and then the price. In equilibrium one country will be more polluted than the other because firms choose different levels of environmental quality of their products. We find that a country’s optimal commodity tax is higher if the domestic firm is the more polluting supplier. Furthermore, non-cooperative commodity tax rates are inefficiently high in equilibrium. This is because, in this framework with environmentally aware consumers, commodity taxes affect the choice of firms regarding their emissions. Therefore, a domestic tax reduction not only raises the profits of the foreign firm but also lowers its emission levels, resulting in higher welfare for the other country. We also analyse the optimal cooperative and non-cooperative commodity and emission taxes with border tax adjustments. With these two policy instruments available, commodity taxes are higher.     

On the effects of emission standards as a non-tariff barrier to trade in the case of a foreign Bertrand duopoly: A note

Employing a model of an environmentally differentiated product market, we analyze how an emission regulation as non-tariff barriers to trade affects imports, the environment, and welfare in the case of a foreign Bertrand duopoly. Related to this issue, we reconsider the result of Moraga-González and Padrón-Fumero [Moraga-González, J.L., Padrón-Fumero, N., 2002. Environmental policy in a green market. Environmental and Resource Economics 22, 419–447] that a strict emission standard on a dirtier product degrades the environment and reduces the net social surplus associated with the valuation of environmental damage, if the marginal social valuation of environmental damage is larger. On the other hand, we show that a strict emission standard on a cleaner product always improves the environment and the net social surplus associated with the valuation of environmental damage.     

On the paradoxical case of a consumer-based environmental subsidy policy

We apply an environmentally differentiated duopoly model to the analysis of environmental policy involving consumer subsidies based on the emission levels of the products consumers purchase. More specifically, we consider the environmental and welfare effects of subsidizing consumers who purchase environmentally friendly goods in the case of a partially covered market with a Cournot duopoly. We show that, paradoxically, the subsidy policy degrades the environment, and that the optimal policy depends on the degree of marginal social valuation of environmental damage. That is, if the marginal social valuation of environmental damage is larger than a certain value, a consumer-based environmental subsidy policy is not socially optimal.     

Mixed Oligopoly and Environmental Policy

We show in this paper that when there are both public and private firms in product markets (a mixed oligopoly) the decision whether to privatize a public firm interacts with the environmental policy of governments. Therefore, the outcome of the decision whether to privatize a public firm may be different if the government internalizes the environmental damage than if the government ignores it. When the government sets a tax to protect the environment, the tax is lower in the mixed oligopoly than in the private one even though the environmental damage is greater. In the mixed oligopoly the marginal cost of the public firm is lower than the market price.     

The Welfare Effects of Environmental Taxation on a Green Market Where Consumers Emit a Pollutant

This paper examines the welfare impact of emission taxes and subsidies in a green market where consumers emit a pollutant through their usage of products produced by duopolists. For this purpose, we employ a discrete?Ccontinuous model including both consumer choice and usage of an environmentally differentiated product in a utility-consistent framework. The findings indicate that an emission tax is always welfare dominant over a subsidy on consumer purchases of the clean product because of its contribution to a reduction in environmental damage. It does this by both inducing firms to improve the environmental qualities of their products and by constraining consumer usage of these products.     

The Timing of Environmental Policy: A Note on the Role of Product Differentiation

We examine the role that product differentiation can play in the design of environmental policy under full commitment and no commitment on the part of the environmental regulator. We consider a setting with two firms selling a differentiated product which generates pollution through emissions. Firms can reduce their emissions by undertaking abatement activities while an environmental regulator taxes emissions. The main results are: (1) When products are highly differentiated, the optimal time-consistent (no commitment) tax is always lower than the optimal pre-commitment tax. As the degree of product differentiation decreases, for relatively efficient abatement technology and high damages, the time-consistent emission tax exceeds the optimal pre-commitment one. (2) Abatement when product differentiation is extensive is higher under the time-consistent regime unless the abatement technology is extremely efficient. The same ranking applies to social welfare. However, as products become more and more similar, these results are (partially) reversed and pre-commitment could lead to both higher levels of abatement and welfare.     

Managerial firms’ profitability,unions, and environmental taxes

This article examines how determining an optimal environmental tax in a Cournot duopoly with unionized labour markets and managerial firms departing from the strict profit-maximization. It is shown that firm-specific monopoly unions that set wages (1) reduce both the environmental tax and environmental damage and (2) counterintuitively, increase firms’ profitability when the abatement technology is not too “efficient”, and the public evaluation of environmental quality is sufficiently high. Within this framework, the work also develops the endogenous game played by firms that must choose between sales delegation (SD) and profit-maximization. Results show that the SD contract always emerges as the unique, deadlock sub-game perfect Nash equilibrium, thereby solving the (prisoner's) dilemma emerging in the related existing literature assuming a competitive labour market.     

Optimal environmental taxes and standards: Implications of the materials balance

This paper investigates the implications of the materials balance for optimal environmental policy. We find that neglecting the materials-emissions relationship - as is common in models of optimal environmental regulation - implies biases, whose sign depends on the regulatory instrument chosen. When emissions are regulated through an emission tax, the seemingly optimal tax is too high. When regulation proceeds through the use of an emission standard, the seemingly optimal standard is too lax.     

Rethinking the optimal level of environmental quality: justifications for strict environmental policy

Traditional environmental theory suggests that the optimal level of a pollution emission occurs when the marginal damage created by the emissions is equal to the marginal cost of reducing the emissions. We argue that the benefits from reducing pollution should be much more broadly defined to include at least three other sources of benefits. First, we develop a game-theoretic model in which firms may under-invest in cost-saving ‘green technologies’. Second, we demonstrate that consideration of future damages and abatement costs leads to a lower current optimal pollution level than that obtained in traditional models. Finally, we show that ecological complexity creates indirect pathways by which greater pollution increases the likelihood of generating irreversible environmental damage. This broader definition of the benefits of pollution abatement yields an optimal level of pollution that may actually be less than the level at which conventionally-measured marginal damages are equal to marginal abatement costs. Thus, environmental policy should be stricter.     

Who should bear the administrative costs of an emissions tax?

All environmental policies involve costs of implementation and management that are distinct from pollution sources’ abatement costs. In practice, regulators and sources usually share these administrative costs. We examine theoretically an optimal policy consisting of an emissions tax and the distribution of administrative costs between the government and regulated sources of pollution. Our focus is on the optimal distribution of administrative costs between polluters and the government and the optimal level of the emissions tax in relation to marginal pollution damage. We demonstrate how the policy variables affect aggregate equilibrium administrative costs and show that these effects are generally indeterminate, as is the effect of the distribution of administrative costs on aggregate emissions. Consequently, the optimal sharing of administrative costs and whether the optimal emissions tax is higher or lower than marginal damage depend on specific contexts.     

Regulating a Polluting Oligopoly: Emission Tax or Voluntary Agreement?

This paper compares, in a polluting oligopoly, an emission tax and a form of environmental policy called voluntary agreement (VA). Here there are two ways of reducing pollution: output contraction and end‐of‐pipe abatement. Given the imperfect competition, firms’ reaction to the tax is sub‐optimal. They reduce output excessively in order to raise the price and do not abate enough. The VA is a take‐it‐or‐leave‐it contract on abatement effort, offered to the firms with the threat of a tax. It has a limited effect on output and always allows higher abatement than the tax. We find that this kind of VA may be more efficient than the tax in a concentrated industry, when pollution is not too harmful and when the abatement technology is rather efficient and cheap.     

The Welfare Effects of Environmental Taxation

Recent literature has investigated whether the welfare gains from environmental taxation are larger or smaller in a second-best setting than in a first-best setting. This question has mainly been addressed indirectly, by asking whether the second-best optimal environmental tax is higher or lower than the first-best Pigouvian rate. Even this indirect question has itself been approached indirectly, comparing the second-best optimal environmental tax to a proxy for its first-best value, marginal social damage (MSD). On closer examination, however, MSD becomes ambiguously defined and variable in a second-best setting making it an unreliable proxy for the Pigouvian rate. Given these observations, the current analysis reevaluates these welfare questions and finds that when compared directly to its first-best value, the second-best optimal environmental tax generally rises with increased revenue requirements. Even in cases where the second-best environmental tax is lower than its first-best value, the welfare gains may be greater than in a first-best setting. These results suggest that the marginal fiscal benefit (revenue recycling effect) exceeds the marginal fiscal cost (tax base effect) over a range of environmental tax rates that, for benchmark models, extends above the first-best Pigouvian rate. These findings reinforce the intuition that environmental policy complements rather than competes with the provision of other public goods.