Using Sensitivity and Scenario Analysis to Examine the Costs and Benefits of Solar to Duke Energy Carolinas

Abstract

The issue of compensation for solar energy is a hotly debated national issue, with numerous solar cost/benefit studies commissioned in recent years. This project builds on existing studies by identifying a feasible range of values for the various benefits and costs that can be attributed to solar power. This range of values is then applied to 15-year (2015-2029) solar power projections from Duke Energy Carolina’s (DEC) 2014 Integrated Resource Plan to provide a net present value (NPV) of solar power to DEC. Since the benefits and costs of solar are controversial, three different scenarios are created, each incorporating different benefit and cost values from the identified feasible range. The results of the three scenarios ranged from a NPV of $ -188M to a NPV $163M. The NPV figures are highly dependent on the values attributed to the various costs and benefits of solar, which the North Carolina Utilities Commission (NCUC) sets biennially in avoided cost proceedings. The variability between the NPVs of solar to DEC in the three different scenarios highlights the necessity for the NCUC to closely evaluate and examine the various costs and benefits of solar in future avoided cost proceedings.