San Juan Replacement Study
On behalf of the Sierra Club, Synapse modeled the electric system in New Mexico using the EnCompass model in both capacity expansion and production cost modes. Synapse comprehensively modeled zero-emission alternatives to a new utility-proposed gas-fired generation option intended to replace the retiring San Juan Generating Station units in New Mexico in 2023. The modeling accounts for the interconnectedness of the electric power grid in the Desert Southwest region, including detailed representation of generation units in Arizona and New Mexico (and portions of Texas and California), and aggregated treatment for resources in the rest of the West.
Synapse finds that a combination of utility-scale and small-scale solar PV, utility-scale battery storage, incremental wind resource procurements, and increased deployment of demand response will provide Public Service of New Mexico with a less-expensive, and lower-emitting alternative than its proposed gas-fired generation, while meeting all reliability requirements. Utility-scale battery storage in particular is a key part of the resource portfolio. Storage resources can be deployed incrementally to provide a firm capacity resource that can be directly controlled by the utility, charged by any grid resources, and provide valuable regulation up and down and ancillary services.