Understanding your electricity costs when growing indoors is important. Not only do you not want to spend too much money but you also don’t want to waste any electricity unnecessarily. This is a quick breakdown and some calculations on understanding your grow light electricity costs as well as possibly using this guide to help you choose the right type of light.

## Table of Contents

## CFL Electricity Calculations

#### Estimated Total Electricity Cost for CFLs and Fans ($0.12/kWh) = $27/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for CFLs: $16/month**

Total hours: 558 light hours/month (CFLs are on 18 hours/day for 31 days)

CFL Wattage: Total of 244W for all CFLs

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $16.

HOURS x COST/HOUR = 558 x (0.12 x 0.244) = $16

**Electricity Cost for Exhaust Fan: $6/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 68W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $6

HOURS x COST/HOUR = 744 x (0.12 x 0.068) = $6

**Electricity Cost for 2 Clip-On Fans: $5/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $5.

HOURS x COST/HOUR = 744 x (0.12 x 0.060) = $5

#### Estimated Total Electricity Cost for CFLs and Fans = $59/month at $0.25/kWh

This includes the cost of running the grow lights and fans.

**Electricity Cost for CFLs: $35/month**

Total hours: 558 light hours/month (CFLs are on 18 hours/day for 31 days)

CFL Wattage: Total of 244W for all CFLs

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $35.

HOURS x COST/HOUR = 558 x (0.25 x 0.244) = $35

**Electricity Cost for Exhaust Fan: $13/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 68W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $13.

HOURS x COST/HOUR = 744 x (0.25 x 0.068) = $13

**Electricity Cost for 2 Clip-On Fans: $11/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $13.

HOURS x COST/HOUR = 744 x (0.25 x 0.060) = $11

## Starter LED Electricity Calculations

#### Estimated Total Electricity Cost for LEDs and Fans ($0.12/kWh) = $23/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for LED Grow Lights: $12/month**

Total hours: 558 light hours/month (LEDs are on 18 lhours/day for 31 days)

LED Grow Light Wattage: Total of 185W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $12.

HOURS x COST/HOUR = 558 x (0.12 x 0.185) = $12

**Electricity Cost for Exhaust Fan: $6/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 68W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $6.

HOURS x COST/HOUR = 744 x (0.12 x 0.068) = $6

**Electricity Cost for 2 Clip-On Fans: $5/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $5.

HOURS x COST/HOUR = 744 x (0.12 x 0.060) = $5

#### Estimated Total Electricity Cost for LEDs and Fans ($0.25/kWh)= $49/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for LED Grow Lights: $25/month**

Total hours: 558 light hours/month (LEDs are on 18 lhours/day for 31 days)

LED Grow Light Wattage: Total of 185W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $26.

HOURS x COST/HOUR = 558 x (0.25 x 0.185) = $26

**Electricity Cost for Exhaust Fan: $13/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 68W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $13.

HOURS x COST/HOUR = 744 x (0.25 x 0.068) = $13

**Electricity Cost for 2 Clip-On Fans: $11/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

HOURS x COST/HOUR = 744 x (0.25 x 0.060) = $11

## 250W HPS Electricity Calculations

#### Estimated Total Electricity Cost for 250W Grow Light and Fans ($0.12/kWh) = $33/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for MH/HPS Grow Light: $17/month**

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

MH/HPS Grow Light Wattage: Total of 250W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $17.

HOURS x COST/HOUR = 558 x (0.12 x 0.250) = $17

**Electricity Cost for Exhaust Fan: $11/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 120W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $11.

HOURS x COST/HOUR = 744 x (0.12 x 0.120) = $11

**Electricity Cost for 2 Clip-On Fans: $5/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $5.

HOURS x COST/HOUR = 744 x (0.12 x 0.060) = $5

#### Estimated Total Electricity Cost for 250W Grow Light and Fans ($0.25/kWh) = $69/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for MH/HPS Grow Light: $35/month**

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

MH/HPS Grow Light Wattage: Total of 250W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $35.

HOURS x COST/HOUR = 558 x (0.25 x 0.250) = $35

**Electricity Cost for Exhaust Fan: $23/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 120W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is $23.

HOURS x COST/HOUR = 744 x (0.25 x 0.120) = $23

**Electricity Cost for 2 Clip-On Fans: $11/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W each x 2 = Total of 60W

HOURS x COST/HOUR = 744 x (0.25 x 0.060) = $11

## LEC Electricity Calculations

#### $0.12/kWh Electricity Cost – Estimated Total for 315W LEC Grow Light and Fans = $29/month

This includes the cost of running the grow lights and fans if your electricity costs $0.12/kWh (average cost of electricity in the US).

**Electricity Cost for 315 LEC Grow Light: $22/month**

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

LEC Grow Light Wattage: Total of 315W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is ~$21.

HOURS x COST/HOUR = 558 x (0.12 x 0.315) = $21.09

**Electricity Cost for Exhaust Fan: $7/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 75W

At $0.12/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is ~$7.

HOURS x COST/HOUR = 744 x (0.12 x 0.075) = $6.70

#### $0.25/kWh Electricity Cost – Estimated Total for 315W LEC Grow Light and Fans = $58/month

This includes the cost of running the grow lights and fans if your electricity costs $0.25/kWh (the typical cost of electricity in big cities in the US)

**Electricity Cost for LEC Grow Light: $44/month**

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

LEC Grow Light Wattage: Total of 315W

At $0.25/kWh (everyone is charged different rates, but this is typical for big cities), the monthly cost of electricity for the light is ~$44.

HOURS x COST/HOUR = 558 x (0.25 x 0.315) = $43.94

**Electricity Cost for Exhaust Fan: $14/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 75W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is ~$14.

HOURS x COST/HOUR = 744 x (0.25 x 0.075) = $13.95

## 400W HPS Electricity Calculations

#### Estimated Total Electricity Cost for 400W Grow Light and Fans = $96/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for MH/HPS Grow Light: $56/month**

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

MH/HPS Grow Light Wattage: 400W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is…

HOURS x COST/HOUR = 558 x (0.25 x 0.400) = $56

**Electricity Cost for Exhaust Fan: $23/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 120W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is…

HOURS x COST/HOUR = 744 x (0.25 x 0.120) = $23

**Electricity Cost for 1 Clip-On Fan: $6/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 30W

At $0.25/kWh (everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is…

HOURS x COST/HOUR = 744 x (0.25 x 0.030) = $6

**Electricity Cost for Oscillating Fan: $11/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 55W

HOURS x COST/HOUR = 744 x (0.25 x 0.055) = $11

## 600W HPS Electricity Calculations

#### Estimated Total Electricity Cost for 600W Grow Light and Fans = $128/month

This includes the cost of running the grow lights and fans.

**Electricity Cost for MH/HPS Grow Light: $84/month** (based on $0.25/kWh)

Total hours: 558 light hours/month (grow lights are on 18 hours/day for 31 days)

MH/HPS Grow Light Wattage: 600W

**$0.25/kWh **(everyone is charged different rates, but this is about average for cities), the monthly cost of electricity for the light is…

HOURS x COST/HOUR = 558 x (0.25 x 0.600) = $84

**Electricity Cost for Exhaust Fan: $23/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 120W

HOURS x COST/HOUR = 744 x (0.25 x 0.120) = $23

**Electricity Cost for 2 Oscillating Fans: $21/month**

Total hours: 744 fan hours (fan is on 24 hours/day for 31 days)

Exhaust Fan Wattage: 55W x 2 = 110W

HOURS x COST/HOUR = 744 x (0.25 x 0.110) = $21