electricity use formula by lights

[HappyJackal]

Hey Farmers~
Somewhere I saw a rule of thumb for planning your electricity use based on your lights usage. It was expressed as: "Plan on using X kWh per 1000 watts of lighting used to account for ancillary devices."
This was, I think, based on a closed environment system with aircooled lights, and air conditioner and dehumidifier for climate control. I seem to remember it was somewhere around a quarter to a third again as much as the lights drew. Does anyone have this?
Thanks...

 

[sedate]

This was, I think, based on a closed environment system with aircooled lights, and air conditioner and dehumidifier for climate control. I seem to remember it was somewhere around a quarter to a third again as much as the lights drew. Does anyone have this?

That sounds right about correct to me.

You should use a bit more than one kwh per 1000w lamp per hour - adding ancillary devices and accounting for efficiency/resistance losses - should account for another 25 - 50% on top of that - obviously chillers and a/c units - things that use a compressor - will bring that number in towards the upper end, where simple fans would bring that number in toward the bottom range.

So a rough guess of 1.2 - 1.5 kwh/per 1000w lamp is very reasonable.

kwh's usually run about 10 cents a piece after local taxes and fees - so running a single 1000 on 12/12 for 30 days should come in at right around $40/month, before ancillary devices are factored in.

 

[HappyJackal]

My thanks, sedate, a blessing on your fields.

 

[scrapiron]

Here is a couple formulas for you. To calculate cost, multiply the bulb wattage X the hours of operation and divide by 1000. This will give you the kilowatt hours of electricity consumed. Next check your power bill and see what the kilowatt per hour cost is for your consumption. Multiply the amount consumed by the kw/hr fee and you have the total cost for that light.
Ok, here we go. I have a crop in veg (18/6 light schedule) under a 400w light. My local kw/hr rate is .08 cents.

400w X 18hours a day = 7200 divided by 1000 = 7.2kwh consumption X .08 rate = .576 cents per day to run the light. X 30 days in the month = $17.28 per month to run my 400w at 18 hours a day.

Hope this helps

 

[JoE_AnTiX77]

thanx this helps a lot in estimating the electrical cost...