Power systems of the future are likely to require additional flexibility due to the operating characteristics of many clean energy technologies, particularly those relying on renewable energy sources. This subject has been well studied from an operational perspective, but it has been more difficult to incorporate into capacity expansion models (CEMs) that study investment decisions on the decadal scale. The primary purpose of this report is to present new capabilities that were developed for a particular CEM, NREL's Resource Planning Model (RPM), to better reflect the impact of variable wind and solar generation on system operations and resource adequacy, and, complementarily, to model energy-constrained flexibility resources.
