Samuel Kortum, David A. Weisbach

We derive the optimal unilateral policy in a general equilibrium model of trade and climate change where one region of the world imposes a climate policy and the rest of the world does not. A climate policy in one region shifts activities—extraction, production, and consumption—in the other region. The optimal policy trades off the costs of these distortions. The optimal policy can be implemented through: (i) a nominal tax on extraction at a rate equal to the global marginal harm from emissions, (ii) a tax on imports of energy and goods, and a rebate of taxes on exports of energy but not goods, both at a lower rate than the extraction tax rate, and (iii) a goods-specific export subsidy. The policy controls leakage by combining supply-side and demand-side taxes to control the price of energy in the non-taxing region. It exploits international trade to expand the reach of the climate policy. We calibrate and simulate the model to illustrate how the optimal policy compares to more traditional policies such as extraction, production, and consumption taxes and combinations of those taxes. The simulations show that combinations of supply-side and demand-side taxes are much better than simpler policies and can perform nearly as well as the optimal policy.

Areas of Focus: Climate Change
Definition
Climate Change
Climate change is an urgent global challenge. EPIC research is helping to assess its impacts, quantify its costs, and identify an efficient set of policies to reduce emissions and adapt...
Climate Law & Policy
Definition
Climate Law & Policy
As countries around the world implement policies to confront climate change, EPIC research is calculating which policies will have the most impact for the least cost.
A Solution to the Leakage Problem
Definition
A Solution to the Leakage Problem
A simple, clearly legal, and more effective alternative to border tax adjustments could be to tax domestic extraction along with border adjustments on imports and exports of energy.
Energy Markets
Definition
Energy Markets
Well-functioning markets are essential for providing access to reliable, affordable energy. EPIC research is uncovering the policies, prices and information needed to help energy markets work efficiently.
Fossil Fuels
Definition
Fossil Fuels
Under current policies, fossil fuels will play an important role in the energy system for the foreseeable future. EPIC research is exploring the costs and benefits of these fuels as...