The Center for Transportation and the Environment (CTE) partnered with the California Energy Commission (CEC) and subcontracted with Sage Energy Consulting (SAGE) and The Mobility House (TMH) to determine the lowest cost method for Stockton Unified School District to charge 100% of its electric school bus (ESB) fleet based on current operations. The secondary objective was to evaluate the financial benefit and resilience (grid support) profile for Stockton Unified School District with vehicle-to-grid (V2G) based on current operations.
CTE created an operating profile summary report to determine the operating scenario and constraints for an electric fleet. This report included detailed documentation of the operating time, miles driven, and parked & charging time per bus. CTE worked with SAGE and TMH to analyze charging scenarios to determine charging arrangements for at least three scenarios (e.g., AC charging, DC shared charging, containerized DC charging, AC and DC combination). Out of this analysis, CTE created a lowest cost to charge summary report, which summarizes the lowest cost to charge analysis, capital cost summary, operating cost summary, potential revenue sources and projected value, impact of solar and/or battery storage on reducing energy costs, and a summary of total costs for each scenario analyzed.
To conclude the project, CTE created a non-technical summary presentation and report as well as a partner review report to summarize findings. CTE reviewed results with project partners and developed a final blueprint. The final blueprint, Stockton Unified School Lowest Cost to Charge Blueprint, documents findings, recommendations, and generalized conclusions.
