Distributed Energy Resources at Naval Base Ventura County Building 1512: A Sensitivity Analysis

This report is the second of a two-part study by Berkeley Lab of a DER (distributed energy resources) system at Navy Base Ventura County (NBVC). First, a preliminary assessment of the cost effectiveness of distributed energy resources at Naval Base Ventura County (NBVC) Building 1512 was conducted in response to the base's request for design assistance to the Federal Energy Management Program (Bailey and Marnay, 2004). That report contains a detailed description of the site and the DER-CAM (Consumer Adoption Model) parameters used. This second report contains sensitivity analyses of key parameters in the DER system model of Building 1512 at NBVC and additionally considers the potential for absorption-powered refrigeration. The prior analysis found that under the current tariffs, and given assumptions about the performance and structure of building energy loads and available generating technology characteristics, installing a 600 kW DER system with absorption cooling and recovery heat capabilities could deliver cost savings of about 14%, worth $55,000 per year. However, under current conditions, this study also suggested that significant savings could be obtained if Building 1512 changed from its current direct access contract to a SCE TOU-8 (Southern California Edison time of use tariff number 8) rate without installing a DER system. Evaluated on this tariff, the potential savings from installation of a DER system would be about 4% of the total bill, or $16,000 per year. This second report determines the potential DER energy savings and the robustness of such a system by revealing the critical points of various parameters and their effects on the system's design and cost effectiveness. Because energy consumption in Building 1512 is so high, the impact of changing electricity costs and tariff structure is investigated in depth. This study also considers many of the model's other parameters, including technology turnkey and O&M (operation and maintenance) costs, technology lifetime, electricity and demand tariffs, standby charges, cost of capital (real interest rate), and natural gas prices using sensitivity analysis.