Plan runway and taxiway lighting loads with clarity. Add diversity, spare margin, and phase selection easily. Get feeder current, transformer size, and energy totals.
Enter fixture quantities and ratings, then tune demand, spare capacity, and optional harmonics. The calculator returns connected load, demand kVA, current, and energy.
This example mirrors typical values. Change counts and wattages to match your lighting layout.
| Group | Qty | Watts Each | Multiplier | Group Watts |
|---|---|---|---|---|
| Runway Edge Lights | 120 | 45 | 1.00 | 5,400 |
| Threshold/End Lights | 36 | 60 | 1.00 | 2,160 |
| Taxiway Edge Lights | 80 | 30 | 1.00 | 2,400 |
| Approach Lights | 50 | 120 | 1.00 | 6,000 |
| Guidance Signs | 20 | 80 | 1.00 | 1,600 |
| Apron Floodlights | 10 | 250 | 1.00 | 2,500 |
| Total Connected | 20,060 W | |||
Harmonics multiplier uses √(1 + THD²) as a practical approximation for kVA increase from current distortion.
Airfield lighting is a safety-critical electrical load that must remain predictable under normal operations, low-visibility events, and emergency scenarios. A practical load study starts by listing each lighting system as a fixture group, then building up from connected watts to demand and finally to design capacity. This method supports feeder selection, circuit protection checks, standby power sizing, and documentation for commissioning.
Begin with a clear inventory. Typical groups include runway edge lights, threshold and end lights, taxiway edge lights, approach lighting, guidance signs, and apron floodlights. Each group may have different lamp technology, drivers, and controls. That is why this calculator provides a multiplier field: it lets you include driver losses, lamp-factor allowances, or an operational uplift when a group is known to draw more than its nameplate watts.
After connected load is calculated, the next step is realism. Not every circuit runs at full output at the same time, so a demand factor is applied to represent simultaneous operation. Add a spare margin to cover future expansions, replacement technology changes, and maintenance modes. Cable losses are included as a simple allowance that increases kW before demand is applied, helping you avoid underestimating upstream capacity requirements.
Modern LED drivers and constant-current regulators can introduce non-linear current. When you enable harmonics, the calculator applies an apparent-power uplift using THD as a practical approximation. This helps you evaluate whether transformer kVA and upstream equipment ratings remain adequate even when real power is unchanged.
Example data (matches the sample table):
With these values, you can compare connected kW to demand kVA and then select a practical transformer size from common standard ratings. Always validate results against your project constraints: circuit topology, regulator capacity, voltage-drop limits, and applicable local codes. Use the CSV and PDF exports to keep calculations consistent across design reviews, submittals, and maintenance records.
It is a correction factor for driver losses, ballast effects, aging allowances, or known measured uplift versus nameplate watts. Use 1.00 when you have verified fixture wattage.
Use demand kVA with spare margin for upstream capacity decisions like transformers and feeders. Use connected load for energy estimates and for understanding maximum possible wattage.
This allowance provides a quick uplift to avoid underestimating upstream capacity. For final design, perform detailed voltage-drop checks using conductor size, length, temperature, and installation method.
Enable it when fixtures use non-linear drivers or regulators and you have measured or specified THD. It estimates additional apparent power that can affect kVA-based equipment ratings.
Use measured PF if available. Otherwise, use a conservative value from fixture or driver specifications. Lower PF increases kVA and current, which may change feeder and transformer selections.
Phase selection only changes the current calculation. The kW and kVA totals remain the same. Choose the phase configuration that matches your supply and distribution design.
Exports use the most recent successful calculation stored in your session. If you change inputs, press Submit again before downloading CSV or PDF for the updated design set.
Accurate lighting load estimates support safer airfield operations daily.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.