Punctuated shifts or incremental change? A comparative analysis of U.S. state-level renewable energy mandates

Abstract

In the U.S., regulatory policies designed to reduce carbon dioxide emissions from the electric power sector have primarily occurred through the adoption of state-level renewable portfolio standards (RPS). In recent years several states have amended existing renewable energy mandates to establish targets that require 100 % of electricity to be generated from zero-emissions energy sources while, in others, renewable energy objectives have remained stagnant. This study applies Punctuated Equilibrium Theory (PET) to assess whether recent modifications to state-level renewable energy objectives are indicative of punctuated shifts or incremental change. Examination of the dynamics of RPS policy change occurs through a distribution analysis of amendments to renewable energy objectives. The PET framework is then applied to two case studies to examine the factors that contribute to policy stasis and punctuated change to renewable energy targets. The quantitative analysis demonstrates that state-level renewable energy amendments reflect the characteristics of policy change described by PET. The qualitative analysis validates the applicability of the PET framework to understand and explain the dynamics of policy change within this policy subsystem.