Planning for electric power system reliability requires strategic changes when large-scale use of solar electric generation technologies is contemplated. Bulk storage will be required in any long-term evolution of power systems that are dominated by baseload central station plants. The basic relations among loads, conversion technologies, storage, and reliability are characterized. The responses of systems to exogenous uncertainties are studied. Solar electric technologies produce a more diffuse risk profile than systems dominated by central station plants. This makes solar electric power generation more resilient to unplanned disturbances.