Grow lights: electricity cost calculator
Quick answer: a typical grow lights costs about $31/month while in use at the U.S. average electricity price (18.44¢/kWh) — about $377 per year. Your number depends on wattage, runtime and your state — calculate it below.
LED grow lights draw 100–1,000 W depending on canopy size, running 12–18 hours daily on vegetative schedules. A 400 W light at 14 h/day is 5.6 kWh — over $1 per day at average prices.
5.60 kWh/day used · 170 kWh/month in use · 2045 kWh/year at 18.44¢ per kWh
Low, typical and heavy use
Monthly cost while in use, at the U.S. average price of 18.44¢/kWh.
| Scenario | Watts | Hours/day | Per month |
|---|---|---|---|
| Light use | 100 W | 8.4 h | $4.71 |
| Typical | 400 W | 14.0 h | $31.43 |
| Heavy use | 1,000 W | 21.0 h | $117.87 |
Common questions
How much does a grow tent add to my bill?
A single 400 W LED on an 14-hour schedule costs about $31 per month at the U.S. average price, plus fans. Check the light's true wall draw — marketing wattages often overstate it.
Cost in every state
Monthly cost of a typical grow lights (400 W, 14h/day) at each state's average residential price, May 2026.
| State | Avg price | Per month |
|---|---|---|
| Alabama | 16.77¢ | $28.58 |
| Alaska | 28.23¢ | $48.12 |
| Arizona | 15.23¢ | $25.96 |
| Arkansas | 14.36¢ | $24.48 |
| California | 33.25¢ | $56.67 |
| Colorado | 16.16¢ | $27.54 |
| Connecticut | 27.37¢ | $46.65 |
| Delaware | 19.38¢ | $33.03 |
| District of Columbia | 25.40¢ | $43.29 |
| Florida | 15.17¢ | $25.86 |
| Georgia | 15.84¢ | $27.00 |
| Hawaii | 52.00¢ | $88.63 |
| Idaho | 12.35¢ | $21.05 |
| Illinois | 23.85¢ | $40.65 |
| Indiana | 18.15¢ | $30.94 |
| Iowa | 14.14¢ | $24.10 |
| Kansas | 15.13¢ | $25.79 |
| Kentucky | 14.98¢ | $25.53 |
| Louisiana | 14.15¢ | $24.12 |
| Maine | 28.63¢ | $48.80 |
| Maryland | 21.77¢ | $37.11 |
| Massachusetts | 28.82¢ | $49.12 |
| Michigan | 22.01¢ | $37.52 |
| Minnesota | 16.95¢ | $28.89 |
| Mississippi | 16.16¢ | $27.54 |
| Missouri | 13.68¢ | $23.32 |
| Montana | 14.67¢ | $25.01 |
| Nebraska | 13.59¢ | $23.16 |
| Nevada | 13.60¢ | $23.18 |
| New Hampshire | 27.33¢ | $46.58 |
| New Jersey | 23.27¢ | $39.66 |
| New Mexico | 14.12¢ | $24.07 |
| New York | 29.93¢ | $51.02 |
| North Carolina | 15.09¢ | $25.72 |
| North Dakota | 13.61¢ | $23.20 |
| Ohio | 19.52¢ | $33.27 |
| Oklahoma | 13.38¢ | $22.81 |
| Oregon | 16.27¢ | $27.73 |
| Pennsylvania | 21.55¢ | $36.73 |
| Rhode Island | 29.46¢ | $50.21 |
| South Carolina | 16.18¢ | $27.58 |
| South Dakota | 15.73¢ | $26.81 |
| Tennessee | 14.47¢ | $24.66 |
| Texas | 16.44¢ | $28.02 |
| Utah | 12.96¢ | $22.09 |
| Vermont | 24.89¢ | $42.43 |
| Virginia | 17.61¢ | $30.02 |
| Washington | 14.95¢ | $25.48 |
| West Virginia | 16.80¢ | $28.64 |
| Wisconsin | 19.74¢ | $33.65 |
| Wyoming | 14.80¢ | $25.23 |
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Methodology & sources
Cost = watts ÷ 1,000 × hours × price per kWh. Electricity prices are average residential prices by state from the EIA Electric Power Monthly, Table 5.6.A (May 2026). EIA averages include delivery charges and taxes but are not any specific utility tariff — for an exact figure, use the rate from your own bill. Wattage presets reflect common product ranges; check your appliance's nameplate or a plug-in power meter for its true draw.
Last verified: July 30, 2026. Prices refresh automatically each month when EIA publishes new data.