💡 Lighting
How Much Does a Grow Light Cost to Run?
At the current U.S. average rate of 18.4¢/kWh (May 2026), a grow light costs about $23.49 per month at typical usage — 14 hours/day.
Per hour
5.5¢
at 100–650 W
Per day
$0.77
14 hours/day
Per month
$23.49
128 kWh
Per year
$282
1,533 kWh
Grow lights run long photoperiods — commonly 12–18 hours daily — so even efficient LED panels rack up serious kilowatt-hours. A single 300-watt light on a 14-hour schedule uses more electricity than most refrigerators; indoor growing budgets should start with the electric bill.
Calculate it for your home
Per hour
5.5¢
Per day
$0.77
Per month
$23.49
Per year
$282
Uses 128 kWh/month at 18.4¢ per kWh.
Cheapest and most expensive states
Monthly cost at typical usage, using each state's current average residential rate.
Cost in every state
| State | Rate (¢/kWh) | Per hour | Per month | Per year |
|---|---|---|---|---|
| Idaho | 12.4 | 3.7¢ | $15.83 | $190 |
| Utah | 13.0 | 3.9¢ | $16.60 | $199 |
| Oklahoma | 13.4 | 4.0¢ | $17.11 | $205 |
| Nebraska | 13.6 | 4.1¢ | $17.36 | $208 |
| Nevada | 13.6 | 4.1¢ | $17.36 | $208 |
| North Dakota | 13.6 | 4.1¢ | $17.36 | $208 |
| Missouri | 13.7 | 4.1¢ | $17.49 | $210 |
| Iowa | 14.1 | 4.2¢ | $18.00 | $216 |
| New Mexico | 14.1 | 4.2¢ | $18.00 | $216 |
| Louisiana | 14.2 | 4.3¢ | $18.13 | $218 |
| Arkansas | 14.4 | 4.3¢ | $18.39 | $221 |
| Tennessee | 14.5 | 4.3¢ | $18.51 | $222 |
| Montana | 14.7 | 4.4¢ | $18.77 | $225 |
| Wyoming | 14.8 | 4.4¢ | $18.90 | $227 |
| Kentucky | 15.0 | 4.5¢ | $19.15 | $230 |
| Washington | 15.0 | 4.5¢ | $19.15 | $230 |
| Kansas | 15.1 | 4.5¢ | $19.28 | $231 |
| North Carolina | 15.1 | 4.5¢ | $19.28 | $231 |
| Arizona | 15.2 | 4.6¢ | $19.41 | $233 |
| Florida | 15.2 | 4.6¢ | $19.41 | $233 |
| South Dakota | 15.7 | 4.7¢ | $20.05 | $241 |
| Georgia | 15.8 | 4.7¢ | $20.17 | $242 |
| Colorado | 16.2 | 4.9¢ | $20.68 | $248 |
| Mississippi | 16.2 | 4.9¢ | $20.68 | $248 |
| South Carolina | 16.2 | 4.9¢ | $20.68 | $248 |
| Oregon | 16.3 | 4.9¢ | $20.81 | $250 |
| Texas | 16.4 | 4.9¢ | $20.94 | $251 |
| Alabama | 16.8 | 5.0¢ | $21.45 | $258 |
| West Virginia | 16.8 | 5.0¢ | $21.45 | $258 |
| Minnesota | 17.0 | 5.1¢ | $21.71 | $261 |
| Virginia | 17.6 | 5.3¢ | $22.47 | $270 |
| Indiana | 18.2 | 5.5¢ | $23.24 | $279 |
| Delaware | 19.4 | 5.8¢ | $24.77 | $297 |
| Ohio | 19.5 | 5.8¢ | $24.90 | $299 |
| Wisconsin | 19.7 | 5.9¢ | $25.15 | $302 |
| Pennsylvania | 21.6 | 6.5¢ | $27.58 | $331 |
| Maryland | 21.8 | 6.5¢ | $27.83 | $334 |
| Michigan | 22.0 | 6.6¢ | $28.09 | $337 |
| New Jersey | 23.3 | 7.0¢ | $29.75 | $357 |
| Illinois | 23.9 | 7.2¢ | $30.52 | $366 |
| Vermont | 24.9 | 7.5¢ | $31.79 | $382 |
| Washington, D.C. | 25.4 | 7.6¢ | $32.43 | $389 |
| New Hampshire | 27.3 | 8.2¢ | $34.86 | $419 |
| Connecticut | 27.4 | 8.2¢ | $34.98 | $420 |
| Alaska | 28.2 | 8.5¢ | $36.01 | $432 |
| Maine | 28.6 | 8.6¢ | $36.52 | $438 |
| Massachusetts | 28.8 | 8.6¢ | $36.77 | $442 |
| Rhode Island | 29.5 | 8.8¢ | $37.67 | $452 |
| New York | 29.9 | 9.0¢ | $38.18 | $458 |
| California | 33.3 | $0.10 | $42.52 | $510 |
| Hawaii | 52.0 | $0.16 | $66.39 | $797 |
How to lower the cost
- Buy by PPF efficiency (µmol/J), not wattage — modern LED bars deliver the same light for 40% less power than old HPS.
- Use a timer religiously; every extra lit hour is pure cost.
- Reflective surfaces let you run lights lower or farther for the same canopy light.
Frequently asked questions
How much electricity does a grow light use?
A typical grow light draws about 300 watts in use. At 14 hours/day, that works out to roughly 4.2 kWh per day, or 128 kWh per month.
How much does it cost to run a grow light for 1 hour?
At the current U.S. average residential rate of 18.4¢/kWh, one hour costs about 5.5¢. In Idaho (12.4¢/kWh) it's 3.7¢, while in Hawaii (52¢/kWh) it's $0.16.
How much does a grow light cost to run per month?
With typical usage (14 hours/day), expect about $23.49 per month at the U.S. average rate — from $15.83 in Idaho up to $66.39 in Hawaii. Rates are as of May 2026.
Does a grow light use a lot of electricity?
Yes — at typical usage it accounts for roughly 14% of an average U.S. home's monthly consumption (885 kWh), which makes it one of the larger loads in the house.