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.     

How Large are the Welfare Gains from Technological Innovation Induced by Environmental Policies?

This paper examines whether the welfare gains from technological innovation that reduces future abatement costs are larger or smaller than the Pigouvian welfare gains from optimal pollution control. The relative welfare gains from innovation depend on three key factors—the initially optimal level of abatement, the speed at which innovation reduces future abatement costs, and the discount rate. We calculate the welfare gains from innovation under a variety of different scenarios. Mostly they are less than the Pigouvian welfare gains. To be greater, innovation must reduce abatement costs substantially and quickly and the initially optimal abatement level must be fairly modest.     

CO2 abatement policy with learning-by-doing in renewable energy

This paper analyzes the implications of CO₂ abatement when there is endogenous technological change in renewable energy. A multi-sector numerical general equilibrium model for Denmark is proposed to reflect two basic assumptions about technological progress in renewable energy. First, there is learning-by-doing and unit costs of production are a decreasing function of cumulated output. Second, technological progress only benefits new vintages of capital. The learning-by-doing process is calibrated to match current projections for technological progress in wind-based electricity. The implications are a marked reduction in the total and marginal cost of abatement and a decline in the optimal level of near-term abatement.     

Induced technological change and the attractiveness of CO2 abatement policies

This paper investigates the significance of induced technological change (ITC) for the attractiveness of CO₂ abatement policies. We use analytical and numerical general equilibrium models in which technological change results from profit-maximizing investments in R&D. We show that carbon abatement policies have very different impacts on R&D across industries, and do not necessarily raise the economy-wide rate of technological progress. Focusing only on the sectors with positive R&D impacts can lead to substantial underassessment of the GDP costs of CO₂ abatement policies. The presence of ITC implies lower costs of achieving a given abatement target, but it implies higher gross costs (costs before netting out environment-related benefits) of a given carbon tax. Gross costs depend importantly on the efficiency of R&D markets prior to the introduction of CO₂ policies.     

Investment and emission control under technology and pollution externalities

This paper studies incentives to develop advanced pollution abatement technology when technology may spillover across agents and pollution abatement is a public good. We are motivated by a variety of pollution control issues where solutions require the development and implementation of new pollution abatement technologies. We show that at the Nash equilibrium of a simultaneous-move game with R&D investment and emission abatement, whether the free rider effect prevails and under-investment and excess emissions occur depends on the degree of technology spillovers and the effect of R&D on the marginal abatement costs. There are cases in which, contrary to conventional wisdom, Nash equilibrium investments in emissions reductions exceed the first-best case.     

Endogenous technology and tradable emission quotas

We study an international climate agreement that assigns emission quotas to each participating country. Unlike the simplest models in the literature, we assume that abatement costs are affected by R&D activities undertaken in all firms in all countries, i.e. abatement technologies are endogenous. In line with the Kyoto agreement we assume that the international climate agreement does not include R&D policies. We show that for a second-best agreement with heterogeneous countries, marginal costs of abatement differ across countries. In other words, the second-best outcome cannot be achieved if emission quotas are tradable.     

Gross world product and consumption in a global warming model with endogenous technological change

This paper analyzes the macro-economic costs and effects on consumption and energy demand of limiting the global average atmospheric temperature increase to 2 °C. We use a macro-economic model in which there are two competing energy technologies (carbon and non-carbon, respectively), technological change is represented endogenously, and energy is aggregated through a CES function implying positive demand for the relatively expensive non-carbon technology. Technological change is represented through a learning curve describing decreasing energy production costs as a function of cumulative experience. We find that energy savings constitutes an important mechanism for decreasing abatement costs in the short- and medium-term, while the acquisition of additional learning experience substantially decreases abatement costs in the longer-term.     

Joint Management of Emission Abatement and Technological Innovation for Stock Externalities

We investigate how emission abatement and technological innovation provide different solutions to reduce pollutant emissions. In the case of a stock externality emission abatement leads to a smooth and continuous adjustment of emissions. Conversely, technological innovation has to be interpreted as an option on a less polluted environment and can justify the use of a pollution threshold above which it is optimal to start a research and development programme for a less polluting technology. It is shown that technological innovation interferes with the traditional emission abatement approach. The optimal abatement level is logically lowered once the less polluting technology is available; nevertheless a temporary increase in emissions is optimal during the research and development period. The usual Pigouvian tax system proves to remain an efficient corrective instrument. A numerical application to the Greenhouse effect is provided.     

Industry-level emission trading between power producers in the EU

This paper investigates how restrictions for emission trading to the energy-intensive power sector will affect the magnitude and distribution of abatement costs across EU countries vis-à-vis a comprehensive EU emission trading regime. It is found that emission trading between European power sectors allows the harvest of a major part of the efficiency gains provided by full trade as compared to strictly domestic action. However, trade restrictions may create a more unequal distribution of abatement costs across member states than is the case for a comprehensive trade regime. The reason for this is that restricted permit trade enhances secondary terms-of-trade benefits to EU member countries with low marginal abatement costs at the expense of the other EU member states.     

Static and dynamic efficiency of pollution control strategies

A great deal of the economic literature on pollution control strategies concentrates on the efficiency of environmental policy instruments. Most analytical studies in this field show that market instruments are more efficient with respect to the cost of pollution abatement of a given number of polluters than non-market instruments. According to several analytical studies, market instruments should also be more efficient with respect to innovation in pollution abatement equipment than non-market instruments. In the empirical literature a great number of case studies exist with estimations of the savings of abatement costs of market instruments in a situation without technological progress. Empirical studies about the impact of environmental policy market instruments on the abatement costs in situations with technological progress are lacking.The purpose of this paper is to fill this gap. The paper deals with an empirical estimation of abatement costs for the emission of SO₂ of coal-fired electricity units in the Netherlands from 1985 to 2000. First, the working of market instruments and non-market instruments (the existing environmental policy of the Dutch government) is simulated in a static situation. Second, we analyse the learning effects of flue gas desulphurization. The efficiency advantage of market instruments turns out to be larger in a situation of technological progress than in a static situation.     

Long-Run Implications for Developing Countries of Joint Implementation of Greenhouse Gas Mitigation

Joint Implementation (JI) calls for cooperation between industrialized and developing countries in the mitigation of greenhouse gas (GHG) emissions. However, a major concern of potential host countries is that, if they utilize their low-cost options for JI now, they will be left with only high cost options in the future, thereby penalizing them at a time when they may be obligated to mitigate GHGs themselves. This paper formalizes this hypothesis by utilizing an optimal control framework analogous to the Hotelling model of non-renewable resource extraction. The results are that cumulative abatement effects can impose costs on the future, but that they can be offset by technological change, market power, or compensation.     

Optimal environmental taxation and enforcement policy

We study the optimal environmental taxation and enforcement policy when (i) the regulator does not know the firms’ abatement costs, (ii) penalties for tax evasion are limited, and (iii) monitoring of pollution is costly. We show that the threat of being audited alter the usual firms’ incentives to over-estimate their abatement costs. In particular, depending on the firms’ abatement costs, the optimal policy may involve over or under-deterrence compared to the full information outcome. We then investigate the properties of a pollution standard. We show that this policy comes close to an environmental tax once the economic incentives of the accompanying enforcement policy are considered.     

Optimal dynamic environmental policies of a profit maximizing firm

In this paper we study the optimal environmental policy of the firm for different scenarios dependent on (costs of) production technologies, financing costs, and governmental policy. The governmental instruments to be considered are:

Using Tradeable Permits to Achieve Sustainability in the World's Large Cities: Policy Design Issues and Efficiency Conditions for Controlling Vehicle Emissions, Congestion and Urban Decentralization with an Application to Mexico City

Many large cities in the world have serious ground level ozone problems, largely the product of vehicular emissions and thus the argued unsustainability of current urban growth patterns is frequently blamed on unrestricted private vehicle use. This article reviews Mexico City's experience with vehicle use restrictions as an emissions control program and develops the conditions for optimal quantitative restrictions on vehicle use and for complementary abatement technologies. The stochastic nature of air pollution outcomes is modelled explicitly in both the static and dynamic formulations of the control problem, in which for the first time in the literature the use of tradeable vehicle use permits is proposed as a cost-effective complement to technological abatement for mobile emissions control. This control regime gives the authorities a broader and more flexible set of instruments with which to deal more effectively with vehicle emissions, and with seasonal and stochastic variation of air quality outcomes. The market in tradeable vehicle use permits would be very competitive with low transactions costs. This control policy would have very favorable impacts on air quality, vehicle congestion and on urban form and development. Given the general political resistance to environmental taxes, this program could constitute a workable and politically palatable set of policies for controlling greenhouse gas emissions from the transport sector.     

Environmental Regulations,Producer Responses,and Secondary Benefits: Carbon Dioxide Reductions Under the Acid Rain Program

This paper derives a production analysis framework for modeling secondary benefits from environmental regulation, i.e. induced changes in yet unregulated pollutants. We emphasize the various ways in which the producers can respond to environmental regulations, and evaluate them in terms of their costs and their generation of secondary benefits. An application on the US electricity sector illustrates our main point: In our case, abatement technologies that reduce regulated emissions while leaving the plants’ unregulated emissions unchanged appear to be among the least costly producer responses to the existing sulfur and nitrogen regulations, but at the expense of limited secondary reductions in carbon dioxide emissions. This finding raises questions about the magnitude of the much debated secondary benefits from future regulations on carbon dioxide emissions, since similar abatement technologies are currently being developed for carbon dioxide. With new environmental issues emerging over time, our findings suggest that regulators should signal the possibilities of new regulations on connected pollutants to producers. Such information may be relevant for producers when choosing current abatement strategies—with minor cost increases to deal with today’s issues, overall compliance costs for near-future environmental problems may be lowered.     

Strategic Investment in Climate Friendly Technologies: The Impact of Global Emissions Trading

Our point of departure is that a group of industrialized countries invest in research and development (R&D) of greenhouse gas (GHG) abatement technologies. R&D investments influence the future GHG abatement choices of both industrialized and developing countries. We distinguish between investments that reduce industrialized countries’ abatement costs and investments that reduce developing countries’ abatement costs. Unlike earlier contributions, we include global trading in emission permits. This changes the nature of the game. With global permit trading, industrialized countries should in many cases invest strategically in technologies that only reduce abatement costs at home. This comes in addition to investments abroad. Second, we show that R&D investments always decrease total emissions. Finally, we find that the developing region receiving investments always benefits.     

行业视角下减排成本估算及减排路径研究

碳达峰碳中和是中国经济发展环境治理的战略目标,减排成本与减排路径是该战略实施中两大现实问题。基于行业视角,利用投入产出方法,对行业减排成本、技术减排效应及减排路径展开研究,基本结论如下：①行业减排成本差异大,整体减排成本逐年上升。在三个代表性年份行业最高与最低减排成本相差40-60倍,减排成本绝对差值在1500-3000$/t。在2000-2010年间, 32个行业减排成本均有不同程度的上升, 全社会整体减排成本上升了56.98%。②技术进步的减排贡献较大,部分行业技术减排有限。在产出固定假设下,2000-2010年技术进步实现累计减排57.09亿t,累计技术减排率达到47.88%；但在旅游、住宿餐饮等行业技术减排率为负,技术因素导致的排放不减反增。③行业减排路径应遵循从高碳到低碳的顺序。基于减排成本与技术减排两大因素的减排路径规划显示,优先和重点减排行业主要集中在能源生产供给、加工制造、交通运输、采矿及设备制造等高能耗高排放行业；可相对延后和非重点减排行业主要为食品烟草等传统加工制造业以及金融、房地产等现代服务业。     

Do technology externalities justify restrictions on emission permit trading?

International emission trading is an important flexibility mechanism, but its use has been often restricted on the ground that access to international carbon credits can undermine the domestic abatement effort reducing the incentive to innovate and, eventually, lowering the pace of climate policy-induced technological change. This paper examines the economics that is behind these concerns by studying how a cap to the trade of carbon offsets influences innovation, technological change, and welfare. By using a standard game of abatement and R&D, we investigate the main mechanisms that shape these relationships. We also use a numerical integrated assessment model that features environmental and technology externalities to quantify how limits to the volume, the timing, and the regional allocation of carbon offsets affect climate policy costs and the incentive to invest in innovation and low-carbon technologies.Results indicate that, for moderate caps on the amount tradable emissions permits and sufficiently high technology spillovers, global innovation and technical change would increase and that this additional innovative effort could lead to economic efficiency gains. The numerical analysis confirms that when constraints are close to 15% of domestic abatement, efficiency losses are small because they are partly compensated by more technological spillovers and lower energy prices. Under a broad range of parameters, restrictions are costly for the constrained countries, but always beneficial for unconstrained ones.     

Emission Taxes and Product Differentiation in the Presence of Foreign Firms

Industries characterized by differentiated products are important contributors of greenhouse gases and currently subject to market‐based policies such as emission taxes. In the context of developing countries, fears about foreign investment leaving the country are often used as an argument not to address industry emissions through emission taxes. This paper develops a Cournot model with product differentiation in the presence of abatement efforts where host and foreign firms are subject to an emission tax. The analysis indicates that abatement efforts and differences in pollution intensity coefficients across firms may play a significant role in the characterization of optimal policy. The analysis also suggests that the government may opt to encourage foreign, less pollution‐intensive firms via higher taxation. Additionally, this paper examines how an optimal emission tax may be adjusted as products become more differentiated; industry emissions may fall/rise as a result of more differentiated products. One important contribution of this paper is that it emphasizes the role of abatement efforts, product differentiation, and differences in pollution intensity coefficients across firms in the characterization of the optimal emission tax.     

Dynamic economic analysis of marine pollution prevention technologies: An application to double hulls and electronic charts

Marine pollution associated with shipping accidents has resulted in a Congressional mandate for double hulls on tankers in U.S. waters. In this paper, we formulate a social planner's problem using optimal control theory to examine the relative cost-effectiveness of double hulls and alternative pollution prevention technologies, and the optimal installation strategy for such technologies. The model encompasses the costs and benefits associated with shipping operations, damage to the marine environment, and investment in each technology. A computer simulation of the model is used to evaluate investment strategies for two technological options: double hulls and electronic chart systems. Results indicate that electronic charts may be a far more cost-effective approach to marine pollution control.