This report explores a modular approach to multi-state compliance with the EPA’s Clean Power Plan. Under this approach individual states would develop their own state compliance plans and meet their own state targets, but would develop portions of their plans…

This report concerns the issue of methane leakage during the life cycle of natural gas-fired power generation. Methane leakage is an important issue because methane is a greenhouse gas (GHG) of much greater global warming potential than carbon dioxide (as…

Distributed Energy Resources (DER) are, and will continue to be, a growing component of WECC resources. Historically, new facility investment in distribution systems has been for load growth; more recently, investment in distribution systems has expanded to include DER (on…

This report documents the assumptions in four planning scenarios developed in consultation with an SPSC modeling work group. These scenarios illustrate future state-level resource mixes that could result from strategies that state may employ to comply with the Clean Power…

These reports develop a new methodology for calculating transmission path transfer capabilities that better reflect actual system operating conditions. The new methodology would allow for more active management of path flows by automating the path rating process and using data…

Energy and Environmental Economics (E3) completed the Interim Project Report of the Western Interconnection Flexibility Assessment. This is a collaborative project among WECC, WIEB, NREL and E3 to investigate the operational challenges of increasing levels of variable generation in the…

This report provides an overview of the state of transmission planning in the Western Interconnection. It covers the planning done by the Western Electricity Coordinating Council (WECC), the California Independent System Operator (CAISO), the Northern Tier Transmission Group (NTTG), ColumbiaGrid…

This report provides a roadmap for assessing the reliability challenges associated with high levels of variable energy resources and the retirement of coal plants in the Western Interconnection. The report discusses the types of analysis and data needed to identify…

This report updates and expands upon the information in the National Renewable Energy Laboratory (NREL) report titled “A Review of Variable Generation Integration Charges” published in March 2013. The study found significant differences in western utility VER integration cost study…

This report identifies the capabilities of resource planning models to model flexible generation, as well as determine how utilities and state regulators are assessing the need for flexibility. The study found that the resource planning or load flow models do…