Salt lamp vs. lava lamp: running cost
A lava lamp is cheaper to run: about $10 a year versus $12 for a salt lamp at typical use and 17.99¢/kWh, a $2 difference.
| Salt lamp | Lava lamp | |
|---|---|---|
| Typical watts | 15 W | 25 W |
| Watt range | 3–25 W | 15–100 W |
| Typical use | 12 hours a day | 6 hours a day |
| Energy per year | 66 kWh | 55 kWh |
| Cost per hour | 0.3¢ | 0.4¢ |
| Cost per day | 3.2¢ | 2.7¢ |
| Cost per month | $0.99 | $0.82 |
| Cost per year | $12 | $10 |
| Per year in Hawaii (43.51¢) | $29 | $24 |
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What drives the difference
- Salt lamp: Most salt lamps ship with a 15 W incandescent bulb and are often left on many hours a day; 24/7 use adds up to about 130 kWh a year.
- Lava lamp: Lava lamps use an incandescent bulb as both light and heater (25-40 W for standard sizes); they need 1-3 hours to warm up and should not run more than about 8-10 hours at a time.
Ways to cut either cost
Plug-in timer
Automates warm-up and shutoff so it doesn't run all day.
See options on Amazon Plug-in timer
Limits run time to the hours you're in the room.
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Frequently asked questions
Which costs more to run, a salt lamp or a lava lamp?
At typical use and the U.S. average rate (17.99¢/kWh), a salt lamp costs about $12 a year versus $10 for a lava lamp. That's $2 more, or 1.2× as much.
How many watts do salt lamp and lava lamp use?
A salt lamp typically draws 15 W (range 3–25 W). A lava lamp draws 25 W (range 15–100 W). Watts alone don't decide cost. Hours of use, cycling and standby matter just as much.
Rates: EIA, 12 months ending 2026-07. Methodology.