LED Light Bulb (10W A19)

Product Profile

The 10W A19 LED light bulb is the standard replacement for a 60W incandescent lamp — the most common residential lighting format globally. A typical unit weighs approximately 100g and contains a LED module (chip-on-board or discrete LEDs), an aluminum or plastic heat sink, a polycarbonate diffuser globe, a driver PCB with power electronics, and an E26/E27 screw base. Reference products include Philips LED Classic, GE Reveal, and Osram LED bulbs manufactured primarily in Guangdong, China.

At 2.0 kgCO2e per bulb, the manufacturing footprint is modest in absolute terms. The significance of the LED’s embodied carbon must be understood in the context of its operational savings: over a 15,000-hour rated lifespan, a 10W LED consumes 150 kWh of electricity. On the US average grid (386 gCO2e/kWh), that operational electricity generates 57.9 kgCO2e — roughly 29× the manufacturing footprint. On a coal-heavy grid (700 gCO2e/kWh), operational emissions reach 105 kgCO2e.

Why the Score Is What It Is

The LED’s relatively high CCI score per kilogram (20 kgCO2e/kg) reflects the concentration of high-tech components packed into a small, lightweight package:

• LED chip fabrication is the most carbon-intensive step per gram. Metal-organic chemical vapor deposition (MOCVD) of gallium nitride epitaxial layers onto sapphire or silicon carbide substrates requires ultra-high-purity gases (trimethylgallium, trimethylindium, ammonia), high-vacuum reactors, and precise thermal control. Die dicing, phosphor coating, and chip-on-board bonding add further process steps. The chip module itself may weigh only 1–2g but accounts for ~30% of total manufacturing emissions.
• The driver PCB contains a disproportionate carbon burden. Electrolytic capacitors, inductors, MOSFETs, and control ICs require semiconductor fabrication and chemical processing. The driver board (typically 5–8g) has an emission intensity of 40–60 kgCO2e/kg — comparable to smartphone PCBs — due to the density of processed materials.
• Aluminum heat sink provides thermal management. A die-cast aluminum heat sink (typically 20–30g) ensures junction temperature stays below 85°C to preserve LED lifespan. Primary aluminum at ~8–12 kgCO2e/kg makes this component significant despite its modest mass.
• Final assembly in Guangdong on coal-heavy grid. Assembly operations — soldering, screw-base attachment, globe fitting, testing — are electrically intensive relative to the product’s total mass, and China’s grid amplifies the per-kWh emission rate.

Scope Breakdown Detail

Scope	kgCO2e	% of Total	Key Drivers
Scope 1	0.02	1%	Minimal; some soldering flux and conformal coating solvents
Scope 2	0.48	24%	MOCVD reactors, PCB reflow, injection molding, assembly lines (China grid)
Scope 3	1.50	75%	LED chip supply chain, electronic components, aluminum, PC resin, packaging
Total	2.00	100%

Scope 2’s elevated share (24%) reflects the concentration of energy-intensive processes (epitaxy, die bonding, PCB reflow) in China’s coal-heavy grid, which inflates the electricity-based footprint.

Lifecycle Context: Manufacturing vs. Use Phase

The LED’s environmental story is dominated by operational electricity consumption, not manufacturing:

Phase	kgCO2e (US grid, 386 gCO2e/kWh)	% of Lifecycle
Manufacturing	2.0	3.3%
Operation (15,000 hr, 10W)	57.9	96.4%
End of life	0.2	0.3%
Total lifecycle	60.1	100%

Compared to the incandescent bulb it replaces, a 60W incandescent over the same 15,000 hours uses 900 kWh — generating 347 kgCO2e on the US grid. The LED saves approximately 286 kgCO2e over its lifetime despite its higher manufacturing footprint relative to an incandescent (which is essentially a tungsten filament in a glass envelope).

Design Factors That Affect the Score

• Integrated vs. replaceable driver: Integrated LED bulbs (most consumer products) embed the driver in the base, making the entire unit non-repairable and non-upgradable. Modular designs (Cree’s legacy Connected Lighting) allow driver replacement, extending useful life.
• Aluminum vs. plastic heat sink: Many lower-cost bulbs use a plastic heat sink with an embedded aluminum insert or thermal plastic, reducing weight but potentially compromising thermal management and lifespan.
• Driver quality: Premium driver components (high-quality electrolytic capacitors rated for 105°C) extend rated lifespan from 10,000 to 25,000+ hours, substantially reducing the per-hour manufacturing carbon amortization.

Provenance Override

DOE’s SSL program produces the most credible public LCA data for LED products in the US market. Philips Lighting (Signify) has published EPDs for select LED product lines (verified by Intertek) that would qualify as provenance overrides. Chinese manufacturers rarely publish third-party-verified PCFs as of 2026.