Path-Q Solar

How can I estimate the solar production my roof should deliver before accepting a quote?

Answer

Use the proposed system size, panel layout, roof orientation and tilt, shading, local solar resource, equipment assumptions, and expected losses to create an independent annual and monthly estimate. Compare that estimate with the provider's production model and require the assumptions and expected output in writing.

Key points

  • Review the exact panel count, rated power, inverter design, roof planes, orientation, tilt, and shading assumptions.
  • Include losses from temperature, wiring, inverter conversion, soiling, snow, shading, and system availability.
  • Compare monthly estimates rather than relying only on an annual total.
  • Use measured roof or shade data when available and distinguish modeled production from a guarantee.
  • Check whether the quote's savings calculation uses the same production estimate.

What it depends on

  • Site layout and shading
  • Equipment specifications and loss assumptions
  • Local weather and solar-resource data

Risks and trade-offs

  • Small layout or shading changes can materially affect output.
  • A high production estimate may depend on optimistic assumptions.
  • Production is variable and may not match any particular year's result.

Information you may need

  • Detailed proposal and production model
  • Roof measurements, orientations, tilt, and shading assessment
  • Historical utility use and any available local solar data

Your next step

What to do next

Ask for the provider's production model and assumptions, then compare them with an independent solar estimate before accepting the quote.

Path-Q

Find the right next step

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

Loading…

SQ01309