Research Areas

My research on biofuel politics began with research on the US Renewable Fuel Standard (RFS) in my dissertation on US alternative fuels policy. During my post-doc at UC Berkeley's Energy Biosciences Institute, I expanded my research to the California Low Carbon Fuel Standard (LCFS). I also got deeper into the science politics around carbon accounting. The RFS and LCFS are the first two environmental performance standards in the US that are implemented using life cycle assessment (LCA) models, and their inclusion of indirect emissions sets an important and highly contested precedent for future regulations. 

I've published three case studies on biofuel policymaking: (1) Breetz (2015) traces the decision-making for indirect land use change (ILUC) emissions in the LCFS through policy design in the governor's office, scientific advisory reports, and  agency rulemaking. It shows how science-based and values-based arguments were blending during the policymaking. (2) Breetz (2017) compares initial policymaking for the US RFS (2005-2007) and CA LCFS (2006-2009) to identify key policy entrepreneurs and policy windows. (3) Breetz (2020) applies policy feedback theory to the cellulosic biofuel mandates in the RFS, showing how policy design led to political feedbacks that alternately weakened and strengthened the policy over time. These dynamic feedbacks helps to explain both the successes and failures of the policy. 

My research on electric vehicles (EVs) began when I moved to Arizona and discovered the ad valorem property tax on vehicles. This got me curious about how state and local policies might worsen the cost-effectiveness of EVs through value-based taxes and fees. This has developed into a larger research agenda on the costs and benefits of EVs. Much of this work continues to emphasize how these factors are or could be shaped by policy. 

Three projects analyze the cost-effectiveness of EVs using Total Cost of Ownership (TCO)  cost modeling. These papers highlight spatial variation in ownership costs due to policy, prices, and driving behavior. (1) Breetz and Salon (2018) compared the TCO of electric, hybrid, and conventional vehicles in 14 U.S. cities, showing how policies such as sales tax and purchase subsidies significantly impact EV costs. (2) Parker et al. (2021) models TCO by zip code in Los Angeles, accounting for variation in vehicle miles traveled, electricity rates, insurance rates, taxes, and local and utility subsidies. (3) Breetz et al (in prep) develops TCO cost models for 33 emerging market economies, with large variation in costs due to fuel prices as well as import duties, sales taxes, and luxury taxes. 

Two emerging projects explore questions related to EVs and low-income households, addressing a critical gap in EV research: (1) With colleagues from geography and urban planning, I'm running a survey and focus groups on attitudes, infrastructure access, and other factors affecting EV preferences in low- and moderate-income households. (2) With colleagues from sustainability,  I'm studying how EV adoption could affect vehicle emissions in environmental justice neighborhoods in Phoenix. We are designing our adoption scenarios and data visualizations in consultation with cities and other stakeholder groups to enhance their policy relevance. 

Fundamentally, my deepest interests focus on the interplay between politics, policymaking, and technological change. This reflects a perspective of energy as a socio-technical system with dynamic interaction between social, institutional, and technical dimensions. 

Many of my empirical papers make theoretical contributions to understanding policy windows, policy entrepreneurship, and processes of policy feedback. In addition, two theoretically-oriented papers synthesize across multiple cases to identify common patterns of policy and politics: (1) Stokes and Breetz (2018) examines solar, wind, electric vehicle, and biofuel policies at the state and federal levels in the US. It finds that many important policies began as low-profile, minor provisions tucked into omnibus energy legislation, but over time as the clean energy technology industries began to grow, the political conflicts expanded. (2) Breetz, Mildenberger, and Stokes (2018) developed a conceptual model of the policy and political dynamics behind technology cost curves. Cost curves (also known as experience curves) are often misused to tell stories of technological determinism, and we sought instead to show how both the price and quantity dimensions of new energy technologies are affected by policy and politics. 

My research on policies for electricity-sector transitions span several areas, all highlighting how energy transition policies are shaped by institutions and politics. 

Two papers examine the drivers and implementation challenges for a rapidly growing new policy trend: pledges for 100% Renewable Electricity (100RE) in US municipalities. 100RE pledges have been adopted by over 180 cities and towns, but their implementation is uncertain in many cities that lack operational control over electricity procurement. (1) Breetz et al. (2022) uses a matched-pair research design to examine the drivers of adoption, while also raising concerns about what the institutional variables tell us about implementation. (2) Kunkel et al. (2022) uses a mixed-methods design with regression analysis of adoption and case studies of implementation. It finds that cities in different states are pursuing significantly different implementation strategies, with varying success. Cities without municipal utilities, locally responsive co-ops, or community choice aggregation often struggle to implement these ambitious goals, although there are examples of institutional innovation to find new implementation pathways. 

Another current project, in collaboration with three PhD students, examines how five US states are grappling with policies for transition funding in coal communities. Although the states have similar levels of coal dependency, they have adopted significantly different strategies to providing funding for just transitions. We are using comparative case studies to understand these divergent policy pathways and deepen our understanding of advocacy for just transitions. 

In collaboration with my PhD students, I am a co-author on several projects examining energy transitions in the global south.

Two papers examine the evolution of rural solar energy transitions in India: (1) Rajagopalan and Breetz (2022) traces how India's off-grid solar sector developed over a 30-year period. It shows how the locus of innovation gradually shifted from the national government to the private sector, and it also emphasizes how the sector was shaped by shifting national and international policy narratives over time. This contributes to a growing body of literature applying the Multi-Level Perspective to transitions in the global south. (2) Rajagopalan and Breetz (under review) uses fieldwork with rural communities in India to investigate the justice implications of various waves of village electrification (solar lanterns, solar home systems, solar microgrid, and grid electrification). 

Two papers examine innovation systems for clean energy in Mexico: (1) Aguiar Hernandez and Breetz (in prep) uses interviews with industry, research, and policy stakeholders to assess the functional performance of the sectoral innovation system (SIS) for wind and solar. (2) Aguiar Hernandez and Breetz (in prep) similarly maps the technology innovation system (TIS) for green hydrogen in Mexico and identifies technology-push and market-pull strategies for enhancing hydrogen innovation.