DLC (DesignLights Consortium) has two tiers as of V5.1:
DLC Standard:
- Minimum efficacy: typically 100-120 lm/W (varies by category)
- L70 lifetime: ≥ 50,000 hours
- CRI: ≥ 80
- Power factor: ≥ 0.90
- THD: ≤ 20%
DLC Premium:
- Higher efficacy: typically 120-145+ lm/W
- L70: ≥ 50,000 hours (but at higher ambient temp testing)
- Additional requirements: dimming capability, better color consistency, stricter THD limits (≤ 10% or ≤ 20% depending on category)
- Qualifies for HIGHER utility rebates — typically 30-50% more than Standard
The math that matters:
- Warehouse retrofit, 100 high bays, DLC Standard rebate: $50/fixture = $5,000
- Same project, DLC Premium rebate: $80/fixture = $8,000
- DLC Premium product cost premium: typically $15-25/unit
- Net benefit on 100 units: $3,000 - $8,000 extra rebate minus $1,500-2,500 extra product cost = $500-6,500 net savings
When to use Standard: residential, small commercial, non-utility-rebate projects, or when the project size makes the rebate delta irrelevant.
When to use Premium: any project over ~50 fixtures with utility rebates available. The rebate multiplier almost always pays for the product premium.
Pro tip: Check your local utility's qualified products list BEFORE specifying. Some utilities only rebate DLC Premium for certain categories (e.g., high bays, exterior). DLC's QPL is at https://www.designlights.org/search/