The cost of building a commercial scale solar project has dropped dramatically in the last decade. Based on the average cost to build a commercial-scale project compared to the average price paid by commercial utility customers, it is already cheaper to build a solar project. The cost of self-generation is forecast to continue going down, widening the gap with the cost of electricity from the grid.

The forecast component is built on NREL’s ATB models, assuming

  • 300KW system
  • 15.2% capacity factor (Kansas City)
  • 20-year financing (NREL’s default was 30 years)
  • no ITC in prior years or in forecasts (NREL’s R&D model)

Download the full spreadsheet here by clicking on the bottom right of the embedded Excel spreadsheet.

This analysis is used in: Energy Fact; Building a commercial-scale solar project is cheaper than buying from the grid

Additional data

  • EIA commercial electricity 2019-2050:
    • https://www.eia.gov/outlooks/aeo/data/browser/#/?id=8-AEO2020&cases=ref2020&sourcekey=0
    • Browser row: End-use prices > (2019 cents per kilowatt hour) > Commercial (2019 $/kWh)
  • Commercial electricity 2010-2018: EIA https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_3
  • Commercial solar LCOE 2010-2018 NREL: https://www.nrel.gov/docs/fy19osti/72399.pdf
  • Commercial solar LCOE 2019-2060 NREL: ATB forecasts

Code: m161 FinComSolGrid math xbMath