Understanding Self-Consumption Percentage
How we calculate. Self-consumption % = site-used generation ÷ site generation × 100. See our methodology and accuracy policy .
Real-world scenario: A typical Self-Consumption Percentage case uses on-site consumed (mwh) 420 and on-site generated (mwh) 600. Enter the same figures below to reproduce the worked path.
What is Self-Consumption Percentage?
A behind-the-meter / prosumer KPI for PV and CHP. Distinct from renewable share (mix of total energy) and curtailment (unused potential).
- Same meter boundary
- Consumed = generation used on site
- Generated = gross or AC per policy—label it
The Formula
Worked Example
Common Use Cases
- Solar C&I reviews: export vs self-use
- Battery pairing: raise self-consumption
- Tariff analysis: on-site use share
Pro Tips
- Separate self-sufficiency (load covered)
- Freeze AC vs DC generation basis
- Don’t confuse with renewable share %
| Scenario | When to use |
|---|---|
| Percent of a number | Finding a part of a whole (tax, tip, score) |
| Percent change | Comparing old vs new values |
Limitations: Self-Consumption Percentage results are educational energy and utilities planning aids—not engineering, grid-operations, or investment advice. Confirm definitions with your ISO/RTO, plant, and regulatory reporting standards.
Common mistakes
- Swapping part and whole: The denominator must be the full total, not a subset.
- Rounding too early: Carry extra decimal places through multi-step work before rounding the final percent.
- Mixing percent and decimal forms: Enter rates in the format the calculator labels expect.
The worked example for self consumption percentage was verified with the calculator form on this page—enter the same values to confirm the result.
When to use this calculator
- Use this page when your wording matches self consumption percentage and the form labels on screen.
- Use percent of a number for “what is X% of Y?” problems.
- Use number is what percent when you know part and whole and need the percent.
Still unsure about self consumption percentage? Start with the quick answer above, then open the linked calculator that matches your wording.
❓ Frequently Asked Questions
How do I use this self consumption percentage calculator?
For self consumption percentage, enter the values labeled on the form, then press Calculate. Compare the result to the worked example on this page.
What formula does this page use?
See the quick answer and formula box above for self consumption percentage—the same percentage calculator expression is applied to your inputs.
What if my result looks wrong?
When checking self consumption percentage, re-check part vs whole (or rate vs base), rounding, and whether percents were entered as 25 rather than 0.25 when the form expects percents.
Authoritative References
For power system and plant performance concepts, consult: