---
title: "How expensive is it to run a large 40 watt grow light eight hours a…"
description: "How expensive is it to run a large 40 watt grow light eight hours a day per month?"
url: "https://getplanta.com/community/fQipaoQNS2SCTJGI4q9l9w/kgTDwB_ESe-lM5INGmO53Q"
community: "Equipment & Materials"
author: "Plant Grower"
published: "2024-09-20T01:01:49.608287Z"
language: "en"
image: "https://images.getplanta.com/v1/resize/QnbMYf4aZZp1ikYbs4PGQ5_shnGrobhZuTynYKTyhJg/MJrYd1ekSzKpq5LZTUO6Hg.webp?size=large"
---

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# How expensive is it to run a large 40 watt grow light eight hours a…

_Posted by Plant Grower on 2024-09-20_

How expensive is it to run a large 40 watt grow light eight hours a day per month?

![Attachment 1 of 1](https://images.getplanta.com/v1/resize/QnbMYf4aZZp1ikYbs4PGQ5_shnGrobhZuTynYKTyhJg/MJrYd1ekSzKpq5LZTUO6Hg.webp?size=large)

## 7 comments

### Sunny commented on 2024-09-20

It depends on the wattage of the light, the cost of your electricity and the number of hours you run the light each day. The easiest way to calculate is to use one of the online calculators. Search for one of these:  
Grow light cost calculator  
Grow room electricity calculator  
Power Usage Calculator

#### Plant Grower replied on 2024-09-20

Can plants grow from regular ceiling lights?

#### Sunny replied on 2024-09-20

The only plants I’ve seen grow well from ceiling lights are the plants in stores. Stores have lots of strong bright lights.

#### Plant Grower replied on 2024-09-20

Are there any grow lights that run on batteries?

### Hayley commented on 2024-09-20

My lights cost roughly $5.50 a month. I run two of the ones you have pictured and a set that totals 20 watts. I'd guess one of the big lights is a little over $2/month but I haven't looked at my cost spreadsheet in a minute so I'm not 100% on that  
ETA: I run my lights 12 hours a day

### All\_things\_plants commented on 2024-09-20

If it is LED then not much at all

#### Plant Grower replied on 2024-09-20

It says it has 144 LEDs, so it might be one.

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