Energy Optimisation in Lighting Design
Modern lighting can easily come in below 8 W/m² without compromising design. The five disciplines that get you there.
Why Energy Optimisation Matters
Lighting accounts for 20–30% of commercial energy use. Smart design can halve that without compromising visual quality.
W/m² Targets
| Space | W/m² Target |
|---|---|
| Open office | ≤ 8 |
| Premium office | ≤ 6 with daylight harvesting |
| Hotel public | ≤ 10 |
| Hotel guest room | ≤ 6 |
| Retail (low) | ≤ 12 |
| Retail (premium) | ≤ 18 (higher for accent-led) |
| Circulation | ≤ 4 |
Five Disciplines
- Specify high-efficacy LEDs (≥ 100 lm/W)
- Calibrate lux to the actual task, not above it
- Integrate daylight harvesting on perimeter zones
- Occupancy sensing in circulation, meeting rooms, washrooms
- Scheduled scenes that dim ambient when not needed
Common Mistakes
- Specifying only by wattage, not lm/W
- No daylight sensors on perimeter
- No scheduling, lights always on
- Over-lighting commercial zones
Professional Recommendation
Set a W/m² target in the brief. Verify in DIALux. Add controls strategy as a first-class design element, not an afterthought.
Lighting Intelligence by Alya
At Ashwamedha Design Solutions, this is part of our Lighting Intelligence practice, every recommendation is validated through DIALux simulation, lux calculations and visual comfort analysis before it reaches a construction site. Alya, our lighting intelligence platform, packages this thinking into reusable design tools.
Frequently Asked Questions
Is daylight harvesting expensive?+
Sensors and drivers add a small cost. Energy and comfort gains repay it within 1–3 years on most commercial projects.
What is a good lm/W for LEDs?+
100 lm/W and above is the modern standard. Premium architectural LEDs reach 130–160 lm/W.
Related Service
Lighting Intelligence & DIALux
See how this thinking is applied on live projects.
Need help applying this to your project?
Our team can review your space and turn these ideas into a measured lighting design.