Chapter 3 Externalities and Public Policy
Externalities • Externalities are costs or benefits of market transactions not reflected in prices. • Negative externalities are costs to third parties. • Positive externalities are benefits to third parties .
Externalities and Efficiency • The marginal external cost is the dollar value of the cost to third parties from the production or consumption of an additional unit of a good.
Social Costs MSC = MPC + MEC
Figure 3.1 Market Equilibrium, A Negative Externality and Efficiency MPC + MEC = MSC G S = MPC 110 B 10 105 A 100 Price, Benefit, and Cost (Dollars) D = MSB 4.5 5 Tons of Paper Per Year (Millions)
Positive externalities • The marginal external benefit is the dollar value of the benefit to third parties from an additional unit of production or consumption of a good.
Social Benefit MSB = MPB + MEB
Figure 3.2 Market Equilibrium, A Positive Externality and Efficiency Z 45 S = MSC 30 V Price, Benefit, and Cost (Dollars) 25 U H 10 MPB + MEB = MSB MPB 0 Inoculations Per Year (Millions) 10 12
Figure 3.3 A Positive Externality for Which MEB Declines With Annual Output MPBi + MEB = MSB S = MSC F 30 B S' = MSC' A 25 C 20 Price, Benefit, and Cost (Dollars) MPBi 0 10 12 16 20 Inoculations per Year (Millions)
Internalization of Externalities • An externality can be internalized under policies that force market participants to account for the costs of benefits of their actions.
Corrective Taxes to Negative Externalities • Setting a tax equal to the MEC will internalize a negative externality.
Figure 3.4 A Corrective Tax S’ = MPC + T = MSC S = MPC G 110 B Net Gains in Well-Being 105 Tax Revenue = Total External Costs 100 A T 95 Price, Benefit, and Cost (Dollars) D = MSB 4.5 5 Tons of Paper Per Year (Millions)
Results of a Corrective Tax • Price rises. • The tax revenue is sufficient to pay costs to third parties. • Socially optimal levels of production are achieved.
A Polluting Monopolist • Monopoly creates a loss to society. • A negative externality causes a loss as well. • The losses do not necessarily add to one another. In fact, they can cancel each other out.
Figure 3.5 A Second Best Efficient Solution MPC + MEC = MSC F MPC A P M B Price C D = MSB MR Q Q* 0 M Output per Year
Theory of the Second Best • When two opposing factors contribute to efficiency losses, the can offset one another’s distortions.
Corrective Subsidies • Setting a subsidy equal to MEB will internalize a positive externality.
Figure 3.6 A Corrective Subsidy Z 45 S = MSC R 30 V Price, Benefit, and Cost (Dollars) 25 U Subsidy Payments X 10 = MSB D' = MPBi + $20 Y D = MPBi 0 10 12 Inoculations per Year (Millions)
Property Rights and Internalization of Externalities • Externalities arise because some resource users’ property rights are not considered in the marketplace by buyers or sellers of products. • Governments can give businesses the right to emit wastes in the air and water or it can give individuals the right to clean air and water.
Coase's Theorem • By establishing rights to use resources, government can internalize externalities when transactions or bargaining costs are zero.
Limitations of Coase’s Theorem • Transactions costs are not zero in many situations. • However you allocate the property rights, the distribution of income is affected.
Applying Coase's Theorem • The Clean Air Act of 1990 allows for the sale of the "right to pollute." Firms face a tradeoff when they pollute. If they pollute, they forgo the right to sell their emission permits to others. • In markets for electricity, Clean Air Act has motivated firms to shift to natural gas and away from coal as a means of producing electricity.
Figure 3.8 Pollution Rights and Emissions S = Supply of Pollution Rights Price and Marginal Social Benefit D = MSB of Emitting Wastes $20 0 75,000 100,000 Tons of Annual Emissions and Number of Pollution Rights
Figure 3.9 The Efficient Amount of Pollution Abatement MSC Marginal Social Cost and Benefit E MSB A* 0 100 Percent Reduction in Waste Emitted per Year
Regulatory Solutions • Instead of using market forces to force firms to internalize externalities, we can use emission standards and apply these to all market players.
Figure 3.10 Regulating Emissions: Losses in Efficiency From Differences in the Marginal Social Benefit of Emissions Firm A B MEC = MSC C 10 A DQRA MSB Cost and Benefit (Dollars) QA* QA1 Tons of Emissions per Year Firm B MEC = MSC F G 10 H DQRB MSB 0 QB* QR QB1
Figure 3.11 Losses in Efficiency From Emissions Standards When MEC Differs Among Regions Firm C Firm D MSB MEC = MSC X Y Cost and Benefit (Dollars) 20 S Z T MEC = MSC R MSB DQRC QC* QR QR DQRD QD* Tons of Emissions per Year
Costs and Benefits to the EPA • The EPA estimates that annual compliance costs could be in the range of $225 billion per year. • The EPA estimated in 1990 that the benefits of the Clean Air Act were nearly 50 times the costs. • Ninety percent of the benefits are estimated to come from laws pertaining to power plants and factories.