TODAY’S STUDY: Why The U.S. Needs A Western Energy Market
Enhanced Western Grid Integration: A Legal and Policy Analysis of the Effects on California’s Clean Energy Laws
Juliana Brint, Josh Constanti, Franz Hochstrasser, and Lucy Kessler, May 2017 (Yale Law School and Yale School of Forestry & Environmental Studies)
This analysis addresses the legal and policy merits of a transition to a fully integrated electricity grid in the Western United States through the creation of a regional independent system operator. We summarize the increasing constraints that today’s balkanized grid imposes on system-wide electricity costs and reliability, address the potential benefits of enhanced grid integration, and evaluate potential legal risks for key California clean energy policies.
Wind and solar power are the dominant sources of new renewable energy in the United States and can provide numerous benefits to the economy and the environment. However, the variable nature of these technologies can create grid integration challenges for electricity system operators in some circumstances because renewable energy supply does not necessarily track demand. As California increases its renewable energy generation, it often has to curtail or shut down clean energy that is produced when demand is low. In February 2017, the California Independent System Operator (CAISO) warned that it may need to curtail 6,000 megawatts (MW) to 8,000 MW of renewable energy capacity during some hours in the spring of 2017,1 which is equivalent to 60 to 80% of the total installed large-scale solar generating capacity in the CAISO.2 This means that CAISO will not be able to take full advantage of this inexpensive and pollution-free generation. One way to improve grid reliability, minimize curtailments, and reduce the variability of renewable energy is to create a regional independent system operator to balance supply and demand across a larger geographic area.
Within the Western grid (known as the “Western Interconnection”), electricity is managed by 38 separate balancing authorities (BA) across the United States, Canada, and Mexico. All 38 BAs, including CAISO, are part of the synchronized Western Interconnection but each BA is independently responsible for balancing supply and demand in its own territory. In order to improve reliability, cut costs, and increase efficiency, a number of these balancing authorities are partnering in the Western energy imbalance market (EIM), which is managed by CAISO. The EIM is a “real-time market” that adjusts for forecast errors between supply and demand every five minutes. This regional market has demonstrated numerous benefits of enhanced regional grid integration, such as reducing costs and greenhouse gas (GHG) emissions. However, the EIM is limited in that it only allows for incremental adjustments to generation dispatch schedules and only captures a small portion of the region’s wholesale electricity market. CAISO, Western states, and other stakeholders throughout the West are exploring the creation of a more fully integrated regional electricity market that would be comprehensively managed by a single system operator and include a day-ahead market and other benefits. Such a market could enhance utilities’ resource planning, improve grid efficiency and reliability, and save utility customers money while meeting the West’s demand for reliable, affordable, and clean electricity.
This report examines the potential impacts of an integrated Western electricity market on California’s clean energy policies, including the state’s renewable portfolio standard (RPS), the greenhouse gas emissions performance standard (EPS) for long-term contracts with baseload power plants, and the cap-and-trade program established by AB 32, the state’s groundbreaking climate law. We find that enhanced Western grid integration—through the creation of a regional ISO—does not interfere with these clean energy policies, and it instead can assist California in meeting its objectives by creating more market opportunities for renewable energy, reducing greenhouse gas emissions and other pollution, and improving the transmission system’s efficiency and reliability. CAISO is not now, and would not become a policy-making body, but like other multi-state grid operators it would assist the states it serves in achieving their own policy objectives at lower cost while improving electric system reliability.
While California’s clean energy policies could be the subject of future legal challenges, the likelihood and prospects of such challenges would not be affected by enhanced Western grid integration.
Two provisions of the U.S. Constitution pose theoretical threats to California’s clean energy laws: the Supremacy Clause3 and the Commerce Clause.4 Under the Supremacy Clause, a state law is preempted and invalid if it conflicts with a federal law,5 such as the Federal Power Act (FPA) or the Public Utility Regulatory Policies Act (PURPA). Additionally, the “dormant” Commerce Clause imposes limits on state actions that discriminate against out-of-state commerce,6 unduly burden interstate commerce,7 or assert control over conduct that occurs outside the state’s borders.8 Opponents of regional grid integration might argue that the creation of a regional power market could call the legality of California’s clean energy laws into question under either of these two provisions.
Our analysis indicates that the expansion of CAISO into a regional system operator across several states would not make these challenges any more likely to succeed.9 Given the highly interconnected nature of the electric grid in the Western United States through the Western Interconnection, wholesale sales and transmission of electricity in the CAISO footprint are already treated as forms of “interstate commerce”10 subject to regulation by the Federal Energy Regulatory Commission (FERC) under the FPA. California laws and regulations affecting wholesale electricity transactions could be subject to challenges today if they conflict with federal energy law, and those same laws and regulations are already subject to scrutiny under the dormant Commerce Clause. As long as California and other Western states remain within the Western Interconnection, the potential for Supremacy Clause and dormant Commerce Clause challenges will not change. It is noteworthy that to date there have been no such challenges.
In sum, enhanced Western grid integration under a regional system operator would not expose California’s clean energy policies to additional risks of preemption under the FPA or challenges based on the dormant Commerce Clause. Shifting to a regional grid operator would enable more efficient, affordable, and reliable integration of renewable resources without increasing the legal risk to California’s clean energy policies.