The energy-saving lamp market still carries both CFL (compact fluorescent lamp) and LED technologies. For trade buyers sourcing in quantity — whether for refurbishment contracts, buy-to-let portfolios, or commercial facilities — the choice between the two has real cost implications over the lifetime of an installation. This guide gives you the technical and commercial facts without padding.
What is a CFL?
A compact fluorescent lamp works on the same principle as a fluorescent tube: an electrical discharge excites mercury vapour, which produces UV radiation, which in turn excites a phosphor coating to emit visible light.
Key CFL characteristics
- Warm-up time: 30 seconds to 2 minutes to reach full brightness
- Lifespan: 8,000–15,000 hours (dependent on switching frequency)
- Dimming: Only specific CFL types are dimmable; most are not
- Mercury content: CFLs contain a small amount of mercury and must be disposed of at an approved WEEE collection point
- CRI: Typically 80–85
CFL products from current stock
- GE 20W CFL Stick BC B22 (=100W equivalent) — 12,000 hr lifespan, bayonet cap for domestic and commercial pendants
- Philips 18W 2G11 4-pin Dimmable PL-L CFL 3000K — one of the few genuinely dimmable CFL formats, used in architectural downlights
- 9W CFL Stick SES E14 Warm White 2700K — small Edison screw retrofit for table lamps and decorative fittings
- Sylvania 28W 2D GR8 CFL 3500K — the flat circular 2D format for bulkhead and emergency-light fittings in corridors and stairwells
- OSRAM 10W G24q-1 4-pin Dimmable CFL 3500K — dimmable PL format for architectural luminaires with integral dimmer ballasts
What is an LED Lamp?
A light-emitting diode lamp passes current through a semiconductor junction to produce light directly, with no discharge tube and no mercury. LED technology has matured to the point where it now outperforms CFL in most measurable categories.
Key LED characteristics
- Warm-up time: Instant — full brightness at switch-on
- Lifespan: 15,000–25,000 hours (some rated to 50,000 hours)
- Dimming: Increasingly standard, provided the driver and dimmer are compatible
- Mercury content: None
- CRI: Ranges from 80 to 97+ depending on product grade
LED products from current stock
- Diall 8W LED Dimmable MR16 GU5.3 2700K (=50W) — 621 lm, 15,000 hours, dimmable spotlight replacement
- Bell 6W LED Dimmable GU10 2700K Halo Elite (=75W) — mains-voltage LED spotlight with premium Bell driver quality
- Crompton 5W MR16 LED 2700K 12V GU5.3 — direct halogen replacement on existing 12 V transformer circuits
- Diall 5.3W R50 LED E14 SES 2700K (=40W) — 15,000-hour lifespan, instant-on, not dimmable
Head-to-Head Comparison
| Criterion | CFL | LED |
|---|---|---|
| Warm-up to full brightness | 30 sec – 2 min | Instant |
| Typical lifespan | 8,000–15,000 hrs | 15,000–25,000 hrs |
| Energy saving vs incandescent | ~75–80% less | ~85–90% less |
| Dimmable options available? | Limited (specific ballasts only) | Yes — increasingly standard |
| Mercury / WEEE disposal | Required | Not required |
| Operating temperature sensitivity | Performance drops in cold | Minimal effect |
| Colour rendering (CRI) | 80–85 typical | 80–95+ typical |
| Unit cost (trade) | Lower | Moderate to higher upfront |
| Total cost of ownership (10 yr) | Higher | Lower |
When CFL Still Makes Sense
- The fitting uses a magnetic ballast rated for CFL only — swapping to LED requires either a compatible LED driver or a full fitting change.
- Short-term tenancy or temporary installation where capital expenditure must be minimised and lamp life beyond three to five years is irrelevant.
- Specific cap formats where LED retrofits are not yet universally available — the Philips 18W 2G11 Dimmable CFL is one example where the CFL remains a practical first choice.
When LED is the Clear Choice
- High-cycling environments (toilets, corridors, storerooms) — LED is unaffected by switch frequency, which rapidly degrades CFL cathodes.
- Dimming circuits — LED with a trailing-edge dimmer delivers smooth, flicker-free control from 100% to as low as 5% in compatible products.
- Cold environments (external stores, garages, commercial cold rooms) — CFL output drops sharply below 10°C; LED is largely unaffected.
- Long-term cost management — LED’s extended lifespan and lower wattage typically achieve payback within 12–24 months in commercial applications.
Summary
For trade buyers sourcing at scale, LED is the default specification for the majority of applications in 2025. The per-unit cost premium is offset within months by energy savings and the near-elimination of lamp replacement labour costs over a five-year period. CFL remains a valid choice in specific ballast-dependent fittings and short-term installations.
Both CFL and LED lamp ranges are available in stock at Discount Quality Products with free standard UK delivery on all orders.