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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 — MAY 2026 ⚡ 13W typical
1Enter Wattage
2Set Hours
3See Costs
$

US national average. Edit for your local rate.

Daily Energy Use

0.07

kWh / day

Monthly Cost

$0.36

Yearly Cost

$4.37

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 $0.36
Per Year (365 days) 23.73 $4.37
Real-World Comparison

Running a CFL bulb for 5 hours uses about the same energy as charging a smartphone once.

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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.

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