Daylight Autonomy Calculator
Observed duration-weighted occupied threshold exceedance, inclusive equality, not daylight factor/instantaneous uniformity or annual extrapolation. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
Daylight autonomy measures occupied time meeting a chosen illuminance threshold.
Daylight autonomy measures occupied time meeting a chosen illuminance threshold.1
Duration weighting matters when observations represent unequal intervals. Use Daylight Autonomy Calculator to evaluate the supplied inputs under the specific model below.
When to use Daylight Autonomy Calculator
Use Daylight Autonomy Calculator to evaluate the supplied inputs under the specific model below. Establish the units, measurement scope and applicable model or recipe assumptions before entering values.
How to use Daylight Autonomy Calculator and understand its results
- Establish the units, measurement scope and applicable model or recipe assumptions before entering values.
- Enter Observed occupied light lux, Observed matched occupied hours, Caller daylight threshold lux using the field table and validation rules below, then run the tool.
- Read Occupied daylight autonomy fraction and interpret units, signs, ordering and placeholders as explained below.
- If the tool reports an input error, correct that field and rerun. A successful false result, empty match list or unknown-evidence placeholder has the specific meaning described here; check the limitations before applying the result.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedOccupiedLightLux | Observed occupied light lux | array of number | Required; constraints below |
| observedMatchedOccupiedHours | Observed matched occupied hours | array of number | Required; constraints below |
| callerDaylightThresholdLux | Caller daylight threshold lux | number | Required; constraints below |
Enter aligned nonempty nonnegative illuminances in lux and occupied durations in hours, plus a nonnegative caller threshold. Occupied durations must have positive total. Sum durations whose illuminance is greater than or equal to the threshold and divide by all supplied occupied hours. No sampling schedule or daylight simulation is generated.
autonomyFraction = Σduration[lux≥threshold]/Σduration Field order, units and branch conditions follow the implementation explanation above.
| Output field | Meaning | Value type |
|---|---|---|
| occupiedDaylightAutonomyFraction | Occupied daylight autonomy fraction | number |
{
"input": {
"observedOccupiedLightLux": [
100,
300,
500
],
"observedMatchedOccupiedHours": [
1,
2,
1
],
"callerDaylightThresholdLux": 300
},
"output": {
"occupiedDaylightAutonomyFraction": 0.75
}
}Limitations and assumptions
Duration weighting matters when observations represent unequal intervals. Apply the exact scope and assumptions described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are stated above; extremely large inputs or outputs can also be rejected. These errors differ from successful results such as false, no matches or unknown evidence.
Alternative or Complementary methods
Use Daylight Factor for a related task: Compare simultaneous indoor and outdoor daylight illuminance as a percentage; this is distinct from duration-weighted autonomy.
Use Illuminance Uniformity for a related task: Compare minimum and mean illuminance on a measurement grid when spatial uniformity is the question.
References
-
Daylight Autonomy Calculator — tool.io
Similar or alternative tools
- Daylight Factor
Compare simultaneous indoor and outdoor daylight illuminance as a percentage; this is distinct from duration-weighted autonomy.
- Illuminance Uniformity
Compare minimum and mean illuminance on a measurement grid when spatial uniformity is the question.