Lighting & heat
How much does it cost to run a reptile heat lamp?
We will not quote you a number, because your electricity rate is not ours. Here is the arithmetic, and the three places the cost is actually decided.
By Brijon M.Last updated
Running cost = (watts / 1000) x hours per day x your rate per kWh. Look up your own rate on your bill - US residential rates vary substantially by state, and any single figure quoted online will be wrong for most readers. A thermostat reduces the figure, because a controlled source runs at part power rather than continuously at full.
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The calculation
There is no mystery here, and that is the point of the page. For any device:
| Step | What to do |
|---|---|
| 1 | Take the device wattage from the bulb or the unit label |
| 2 | Divide by 1,000 to get kilowatts |
| 3 | Multiply by the hours per day it actually runs |
| 4 | Multiply by your electricity rate per kWh, from your own bill |
| 5 | Multiply by 30 for a monthly figure, or 365 for annual |
We deliberately do not fill in step 4 for you. Average residential electricity prices in the US vary widely between states, and they move; the US Energy Information Administration publishes the current state-by-state averages if your bill is not to hand. A figure we wrote this month would be wrong for most readers and stale for the rest.
The three things that actually decide your bill
1. A thermostat, and which kind
This is the biggest lever and most keepers do not think of it as a cost item at all. An uncontrolled heat source runs at full wattage for every hour it is on. A thermostat only supplies the power needed to hold the setpoint - which, in a room that is already near the target for much of the day, can be a small fraction of full output. Proportional and dimming controllers do this continuously rather than in bursts.
The secondary saving is bulb life. Hard on/off cycling shortens filament bulb life noticeably compared with proportional control, which turns into fewer replacement bulbs per year.
Single-enclosure control
Spyder Robotics Herpstat 1 Proportional Thermostat
Dimming output means the lamp holds the setpoint at part power instead of running flat out and overshooting.
Two enclosures or two sources
Vivarium Electronics VE-300X2 Dual Proportional Thermostat
Two proportional channels at a stated 600 W each, with alarms. One controller instead of two.
2. Photoperiod discipline
Hours are a direct multiplier on the bill, and the published photoperiods are shorter than many setups actually run. Crested geckos drop to 10 hours in winter; leopard geckos to 12. A timer that implements the seasonal reduction is saving you money as a side effect of being correct husbandry. The photoperiod figures are here.
3. Not heating at night when you do not need to
A nightly temperature drop is healthier for these species than maintaining daytime temperatures, and night heat is only required if the room falls below the species minimum. Measuring the room over a few nights before buying a night heat source is both the husbandry answer and the cheap answer. The night heating guide covers it.
Measure before you add a device
Zoo Med Digital Thermometer and Humidity Gauge
A probe in the enclosure overnight tells you whether you need night heat at all. Many rooms never fall below the species minimum.
The line items in a typical setup
| Device | Runs for | Cost behavior |
|---|---|---|
| Halogen basking lamp | Daytime photoperiod | Largest single draw. Thermostat makes the biggest difference here |
| T5 HO UVB fixture | Daytime photoperiod | Modest and constant. Not thermostat-controlled |
| 6500 K daylight lamp | Daytime photoperiod | Modest. LED options draw very little |
| Ceramic heat emitter or radiant panel | Only when the room is below the night minimum | Seasonal. Often zero for much of the year |
| Thermostat and timers | Continuously | Negligible |
Frequently asked questions
How much does it cost to run a reptile heat lamp?
Multiply the wattage by the hours it runs, divide by 1,000, and multiply by your own electricity rate per kWh. We do not quote a figure because US residential rates vary substantially by state and change over time - your bill has the number you need.
Does a thermostat save electricity?
Yes. An uncontrolled source runs at full power for every hour it is on; a thermostat supplies only what is needed to hold the setpoint. Proportional control also extends filament bulb life compared with hard on/off cycling.
Is it expensive to keep a reptile?
The setup is the large cost; the running cost is modest and dominated by the basking lamp. The expensive version of reptile keeping is the one where you buy a starter kit and replace the enclosure, bulb and controller within a year.
Sources
- Electric Power Monthly - average retail price of electricity to residential customers — U.S. Energy Information Administration
- Crested Gecko Temperatures & Humidity — ReptiFiles
- Leopard Gecko Temperatures & Humidity — ReptiFiles
- Ball Python Humidity & Temperature Requirements — ReptiFiles
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