Climate change, public health, and resilience to power outages are of critical concern to local governments and are increasingly motivating investments in on-site solar and storage. However, designing a solar-plus-storage system to co-optimize for climate, health, resilience, and energy bill benefits requires complex trade-offs that are not captured in current analyses. To fill this gap, we integrate the climate and health impacts of grid-purchased electricity into the REopt Lite optimization model using forwardlooking marginal emissions costs. Using this new model, we quantify the impact of including energy bill, climate, health, and/or power outage cost savings on the optimal sizing, battery dispatch, and economic returns of solar-plus-storage on three public building types (a hospital, school, and warehouse) across 14 U.S. cities. We find that monetizing and co-optimizing for climate and health benefits, as compared to only energy bill savings and resilience, increases the net present value of the solar-plus-storage systems by $200k to $5.2M and makes larger systems financially attractive. Our results illustrate significant differences across geographies and building types, highlighting the need for site-specific analyses and associated policies regarding the costs and benefits of solar-plus-storage.