💡 Lighting
How Many kWh Does a CFL Light Bulb (13W) Use?
CFL Light Bulb (13W) energy cost calculator — see your exact daily, monthly, and yearly electricity cost.
Rate — APRIL 2026
⚡ 13W typical
$
US national average. Edit for your local rate.
Daily Energy Use
0.07
kWh / day
Monthly Cost
$0.37
Yearly Cost
$4.47
CFL Light Bulb (13W) — Cost Breakdown
| Period | kWh Used | Cost ($) |
|---|---|---|
| Per Hour | 0.0130 | $0.0024 |
| Per Day | 0.07 | $0.01 |
| Per Month (30 days) | 1.95 | $0.37 |
| Per Year (365 days) | 23.73 | $4.47 |
⚡ Real-World Comparison
Running a CFL bulb for 5 hours uses about the same energy as charging a smartphone once.
3 Ways to Cut Your CFL Light Bulb (13W) Energy Bill
- 🌱
Upgrade to LED when the CFL burns out — LEDs are now cheaper, instant-on, dimmable, and 30% more efficient than CFLs.
- 💡
Leave CFLs on if you'll return within 15 minutes — frequent on/off cycling shortens CFL lifespan significantly.
- ⚡
Dispose of CFLs properly at recycling centers — they contain small amounts of mercury.
Startup Surge Information
CFLs draw a brief spike of about 20–30W for a fraction of a second during ignition, then settle to their rated wattage.