A Brattle team built and ran simulation models to forecast power prices and GHG allowance prices in California and the Western U.S. through 2050, and to assess how the GHG prices and electric sector emissions would be affected by the early retirement of nuclear plants. The modeling team simulated the GHG emissions and price-sensitive emissions reductions from the electric and non-electric (transportation, industrial and commercial) sectors covered under the AB32 program. The model accounts for the banking of allowances over time, as well as the GHG allowance requirements for power imports into California, with and without the additional GHG restrictions under the Clean Power Plan.