Hey i am experimenting with many different types of plants that i want to grow indoors, i was originally thinking of getting a 600 watt HPS lighting system, but because the area i want to grow the plants in is very small, i'm going to get a 400 watt HPS lighting system.

My question is how much electricity will this use, if i keep it on for about 18 hours a day each day.
Can anyone estimate my monthly electricity bill from this?

A single 400W running 18 hrs a day won't be that much.

Thanks for the reply, but can you please give a bit more detail;
an estimated monthly price or something.

thanks.

400 watt is just like leaving a computer on. People leave their computers on all the time. One of the guys in the tech forum explained that it's better to leave your computer on too.

Some more info http://www.growery.org/forums/showfl...50049#50049%A0

I don't know much about electricity bills in australia but in the US it wouldn't bring it up much at all. I think more of what you'd need to consider is the pattern of the flowering cycle, which can easily be hidden. Most people don't even bother hiding that though.

Ok sweet. im interested in starting my own garden, i just don't want my dad to find out, so i didn't want an obvious jump in the electricity bill.

lol wut?

A 400W is gonna generate some heat and hum. You'd have to know how much a kWh is in your area then do the math. And if you can't figure that out, I'd suggest not growing. They're not exactly cheap either.

im going to do it in a shed that he does not enter, so im fine there.
what do you mean by KWH?

Why are you going to vegetate with a HPS light? HPS isn't very good for veg, but it does do the job nonetheless.. If I were you I'd get a 600w, and get a stronger fan to make up for the extra heat, the difference between a 600 and a 400 is phenomenal. Your dad will know something is up when he gets the electricity bill, though, you can't hide from a 50$ hike in the electricity haha.

damn, $50.

i was planning on getting a 600watt but the area im growing in under a table so it is very small, and don't want to kill the plants because of the unequal ratio of HPS to space, if that exists.

A mate was telling me about it, but he does say alot of shit.

http://home.iprimus.com.au/foo7/calc.html

According to this, the average price of a kwh in Aus is $0.167.

Using that calc, a 600w light will set you back $87.77 a year, while a 400w will cost $58.51. (This is all assuming you have in on 24 hours a day for the whole 365 days).

It doesn't actually say, but as it's an Aussie site I'm assuming that's in AU$ as opposed to US$.