Economic, System, and Environmental Implications of High Renewables in the Western U.S.

This report examines the impacts of higher renewable portfolio standards (RPS) on electric sector planning in Arizona and the Western United States. The analysis explores the role of renewables in achieving CO2 reductions and the economic, environmental, and power sector investment implications of renewable standards vis-à-vis alternate approaches to reaching equivalent CO2 goals. Using the U.S. Regional Economy, Greenhouse Gas, and Energy (REGEN) model, results compare differences in generation mixes, system costs, and emissions between scenarios with renewable targets from 30–70% by 2030, increasing to 50–90% by 2050.