This bill, titled the State Planning for Reliability and Affordability Act, amends the Public Utility Regulatory Policies Act of 1978 (PURPA) by adding a new standard concerning electric reliability. It requires electric utilities that utilize integrated resource planning to establish measures ensuring the reliable availability of electric energy over a 10-year period. These measures must focus on maintaining the operation of, or procuring energy from, reliable generation facilities . A reliable generation facility is specifically defined as one capable of continuous operation for at least 30 days, possessing adequate on-site fuel or continuous energy sources, or having contractual fuel supply obligations for the same duration. Furthermore, such facilities must be able to generate electricity during emergency and severe weather conditions and provide essential services like frequency and voltage support. State regulatory authorities and nonregulated utilities are mandated to commence consideration of this new standard within one year of the bill's enactment and complete their determination within two years. However, these obligations do not apply if a State has already implemented a comparable standard, conducted a proceeding to consider it, or if the State legislature voted on its implementation within the three years prior to the bill's enactment.