Path-Q Solar
What should I do if every solar quote recommends a different system size?
Answer
Do not choose by size alone. Ask each provider to explain its load forecast, usable roof area, shading, production target, export assumptions, equipment limits, and future-load assumptions, then compare the proposals using the same inputs.
Key points
- Different sizes may be reasonable if providers are optimizing different objectives.
- A smaller design may focus on self-consumption or constraints; a larger design may anticipate future loads.
- The quote should state expected annual production and the assumptions behind it.
What it depends on
- Historical and future electricity use
- Roof area, orientation, and shading
- Export treatment and bill structure
- Equipment and interconnection limits
- Financial objective and budget
Risks and trade-offs
- Oversizing can increase cost and produce energy with lower value.
- Undersizing can leave future loads dependent on grid purchases.
- Unstated assumptions make production and savings claims impossible to compare.
Information you may need
- Normalized annual and monthly usage
- Future loads such as EVs, heating, or storage
- Roof layout and shade analysis
- System production, price, and export assumptions from each quote
Your next step
What to do next
Create a common assumptions brief and request revised proposals or a written explanation for each size difference.
Path-Q
Find the right next step
Answer a few questions and we’ll narrow your options.
Loading…
SQ01564