How much does it cost to run an LED grow light?
An LED grow light drawing 300 watts, used 14 hours a day, uses about 4.20 kWh per day and costs about $0.82 per day, $24.82 per month, and $297.56 per year at the US average residential rate of 19.4¢/kWh. Enter your own wattage, hours, and state below for an exact figure.
Estimates only — based on typical wattages and average state rates, not your actual bill.
What drives the cost
Grow lights are among the highest-cost lighting loads in a home because they run 12-18 hours a day at hundreds of watts. LED fixtures use substantially less than the older HID lamps they replaced, but long daily photoperiods mean even efficient fixtures accumulate real cost over a season.
Cost at different daily usage
Same LED grow light at 300 watts, run for different amounts of time, at 19.4¢/kWh.
| Usage | kWh/day | Per day | Per month | Per year |
|---|---|---|---|---|
| 7 h/day | 2.10 kWh | $0.41 | $12.41 | $148.78 |
| 14 h/day | 4.20 kWh | $0.82 | $24.82 | $297.56 |
| 21 h/day | 6.30 kWh | $1.22 | $37.22 | $446.33 |
| 24 h/day | 7.20 kWh | $1.40 | $42.54 | $510.09 |
Cost by model power draw
Not all models are equal. At 14 h/day, here is what the range costs.
| Model | Power | kWh/day | Per day | Per month |
|---|---|---|---|---|
| Low-draw model | 100 W | 1.40 kWh | $0.27 | $8.27 |
| Typical | 300 W | 4.20 kWh | $0.82 | $24.82 |
| High-draw model | 1,000 W | 14.00 kWh | $2.72 | $82.72 |
Cost by state
An LED grow light at 300 W for 14 h/day, priced at each state's average residential rate.
| State | Rate | Per day | Per month | Per year |
|---|---|---|---|---|
| Alabama | 16.8¢ | $0.70 | $21.44 | $257.08 |
| Alaska | 28.2¢ | $1.19 | $36.09 | $432.77 |
| Arizona | 15.2¢ | $0.64 | $19.47 | $233.48 |
| Arkansas | 14.4¢ | $0.60 | $18.36 | $220.14 |
| California | 33.2¢ | $1.40 | $42.51 | $509.72 |
| Colorado | 16.2¢ | $0.68 | $20.66 | $247.73 |
| Connecticut | 27.4¢ | $1.15 | $34.99 | $419.58 |
| Delaware | 19.4¢ | $0.81 | $24.78 | $297.10 |
| District of Columbia | 25.4¢ | $1.07 | $32.47 | $389.38 |
| Florida | 15.2¢ | $0.64 | $19.39 | $232.56 |
| Georgia | 15.8¢ | $0.67 | $20.25 | $242.83 |
| Hawaii | 52.0¢ | $2.18 | $66.48 | $797.16 |
| Idaho | 12.3¢ | $0.52 | $15.79 | $189.33 |
| Illinois | 23.9¢ | $1.00 | $30.49 | $365.62 |
| Indiana | 18.1¢ | $0.76 | $23.20 | $278.24 |
| Iowa | 14.1¢ | $0.59 | $18.08 | $216.77 |
| Kansas | 15.1¢ | $0.64 | $19.34 | $231.94 |
| Kentucky | 15.0¢ | $0.63 | $19.15 | $229.64 |
| Louisiana | 14.2¢ | $0.59 | $18.09 | $216.92 |
| Maine | 28.6¢ | $1.20 | $36.60 | $438.90 |
| Maryland | 21.8¢ | $0.91 | $27.83 | $333.73 |
| Massachusetts | 28.8¢ | $1.21 | $36.85 | $441.81 |
| Michigan | 22.0¢ | $0.92 | $28.14 | $337.41 |
| Minnesota | 16.9¢ | $0.71 | $21.67 | $259.84 |
| Mississippi | 16.2¢ | $0.68 | $20.66 | $247.73 |
| Missouri | 13.7¢ | $0.57 | $17.49 | $209.71 |
| Montana | 14.7¢ | $0.62 | $18.76 | $224.89 |
| Nebraska | 13.6¢ | $0.57 | $17.37 | $208.33 |
| Nevada | 13.6¢ | $0.57 | $17.39 | $208.49 |
| New Hampshire | 27.3¢ | $1.15 | $34.94 | $418.97 |
| New Jersey | 23.3¢ | $0.98 | $29.75 | $356.73 |
| New Mexico | 14.1¢ | $0.59 | $18.05 | $216.46 |
| New York | 29.9¢ | $1.26 | $38.26 | $458.83 |
| North Carolina | 15.1¢ | $0.63 | $19.29 | $231.33 |
| North Dakota | 13.6¢ | $0.57 | $17.40 | $208.64 |
| Ohio | 19.5¢ | $0.82 | $24.96 | $299.24 |
| Oklahoma | 13.4¢ | $0.56 | $17.11 | $205.12 |
| Oregon | 16.3¢ | $0.68 | $20.80 | $249.42 |
| Pennsylvania | 21.6¢ | $0.91 | $27.55 | $330.36 |
| Rhode Island | 29.5¢ | $1.24 | $37.66 | $451.62 |
| South Carolina | 16.2¢ | $0.68 | $20.69 | $248.04 |
| South Dakota | 15.7¢ | $0.66 | $20.11 | $241.14 |
| Tennessee | 14.5¢ | $0.61 | $18.50 | $221.83 |
| Texas | 16.4¢ | $0.69 | $21.02 | $252.03 |
| Utah | 13.0¢ | $0.54 | $16.57 | $198.68 |
| Vermont | 24.9¢ | $1.05 | $31.82 | $381.56 |
| Virginia | 17.6¢ | $0.74 | $22.51 | $269.96 |
| Washington | 14.9¢ | $0.63 | $19.11 | $229.18 |
| West Virginia | 16.8¢ | $0.71 | $21.48 | $257.54 |
| Wisconsin | 19.7¢ | $0.83 | $25.24 | $302.61 |
| Wyoming | 14.8¢ | $0.62 | $18.92 | $226.88 |
How to cut the cost
- Match fixture wattage to canopy area rather than buying the biggest light available.
- Use a timer and run the shortest photoperiod your plants actually need.
- Hang lights at the correct height — too high wastes output on walls and floor.
- Use reflective surfaces so less light is lost outside the growing area.
Compare with related appliances
Monthly cost at typical usage and 19.4¢/kWh.
Questions
How much does it cost to run a grow light?
At 300 watts for 14 hours a day, about 4.2 kWh a day — one of the larger discretionary loads in a home. The state table below shows monthly cost where you live.
How do you calculate what an LED grow light costs to run?
Multiply its wattage by the hours it runs per day, divide by 1,000 to get kilowatt-hours, then multiply by your electricity rate. For an LED grow light: 300 W × 14 h ÷ 1,000 = 4.20 kWh per day, which at 19.4¢/kWh is $0.82 per day.
How many watts does an LED grow light use?
Typically 300 watts, with most models falling between 100 and 1,000 watts. The label on the appliance or its power supply gives the figure for your specific unit.