Path-Q Solar

How does selling excess solar electricity affect the system's payback period?

Answer

Selling or exporting excess electricity shortens payback only to the extent that the credited value of those exports contributes meaningful cash or bill credits. If exports are compensated below the value of self-consumed energy, a system that produces large excesses may have a longer payback than one sized closer to on-site use.

Key points

  • Model self-consumed energy and exported energy separately.
  • Use the applicable export price, credit, settlement period, and any limits or curtailment assumptions.
  • Export value may change over time and may not equal the retail purchase rate.
  • Oversizing for exports can increase cost without producing proportional value.

What it depends on

  • Export compensation and tariff rules
  • Load profile and self-consumption rate
  • System size and production profile
  • Future changes to export treatment

Risks and trade-offs

  • Assuming retail value for all generation can overstate savings.
  • Export rules may change during the system's life.
  • A smaller system may have better economics but provide less energy or resilience.

Information you may need

  • Current export tariff or credit terms
  • Hourly load and production profiles
  • System-size alternatives
  • Sensitivity analysis for future export value

Your next step

What to do next

Compare system sizes using separate values for self-consumption and exports under current and conservative export assumptions.

Path-Q

Find the right next step

Answer a few questions and we’ll narrow your options.

Loading…

SQ01189