Cost Analysis of Renewable Technologies for NCPA

CLIENT: Northern California Power Authority

NCPA was interested in the cost differences between independently developing renewable energy projects or purchasing renewable energy through power purchase agreements (PPAs). IEC provided NCPA with an analysis of the Levelized Cost of Generation (i.e. Busbar Costs) and PPA contract prices for both commercially available and emerging renewable technologies.

To achieve the project objective, IEC compiled many different pieces of currently published industry information to provide a comprehensive analysis of renewable generation technologies and their respective costs. As such, the results of this study will help NCPA determine what renewable technologies will be the most economical to pursue.

For this analysis, IEC identified, collected, and analyzed publicly available data and reports regarding the financial and performance characteristics of commercially available and emerging renewable technologies including:

  • Biomass (dairy anaerobic digester, fluidized bed boiler, waste water anaerobic digester, and integrated gasification combined cycle);
  • Geothermal (binary and dual flash);
  • Small Hydro (in conduit and impoundment);
  • Solar Photovoltaic (single axis tracking, fixed tilt, thin firm fixed tilt, and concentrating dual axis tracking;
  • Solar Thermal (parabolic trough, Stirling dish, compact linear fresnel reflector, and central power tower); and
  • Wind (class 5)


Once the data was collected, IEC used our financial model that calculates the COG and PPA price for each renewable technology.IEC completed this study on a fast-track schedule and was able to provide a complete report to NCPA within the requested two-week timeframe.