Inverter question / Solar System - Check My Work?

[DIY Guy]

Well, between two refridgerators, a hot tub, and the size of the house in general, I would think my house would use more than an average house, but 7kWh a month? that's ridiculous! And those 855 are only costing me US$35... so although I'm not sure on the exchange rate at the moment, I'm pretty darn sure it's not that extreme!

(maybe just the difference in house size? I don't know about the size of houses there in Sydney, but being in a metropolitan area, compared to here in Colorado, where we're fairly rural, plus not using dry cleaning, cooking every night instead of going out, etc, maybe it's not wrong numbers? All I know is the numbers are straight off the electric bill, so unless Xcel is lying to me, I don't know...)

Anyways, where were we, ah, yes, the hot tub. As I think I've said before, I don't really want to deal with a manual heating system (ok not really manual, but you know what I mean.) as that basically means I'd be designing my own hot tub, and I'd much rather just power the one that's already installed, and not have loose piping running around my yard for my dogs to chew/trip on, or to have to destroy the brand new slab I layed for the hot tub in order to bury pipes.

I might have to go Resqueline's route and try to find for myself how much power the hot tub actually uses, see if this project is even fiscally plausible.

 

[donkey]

i am assuming the 10kw is not used constantly but at time of heating and pumping. when the pumps and heating are all running it would utilise the full 10kwh. but when the tub is not pumping(spa setting) and is at a decent temp that would shut off. given the size of an averagage hot tube the heating element may reamin idle for 1-3 hours depending on settings, use and if it is indoors or in the open. the 10kwh reccomendation is for when the water needs to be heated and pumped at once. that is why, i believe, your powerbill does not show 1000kwh.

 

[(*steve*)]

I just got my latest power bill in the post this last week for 3, yes Three, months I used 21 kWh which cost me AU$330

I think you may be reading the kWh/day part of your bill

 

[donkey]

i am still shocked at the price though... that works out to be 4c per kwh..... wicked i am paying 5 times that onpeak

 

[DIY Guy]

Well donkey, I'd reply to your PM in a both informative and humorous manner, but I can't for another 2, well make that 1 post... So I guess I'll spell it out here.

I was wrong, it was actually $93.65 US ($88.23 AU) which comes out to about 11 cents per kWh, which is a bit more reasonable. I noticed that the site you cited had some tariffs around there, but I don't really have a clue what their qualifications even mean, or why they call them tariffs in the first place.

Although I agree house size wouldn't affect price per kWh, it would affect kWh usage due to heating, a/c etc.

The two things I think may cause a difference are the semi rural area, leading to ease of power distribution compared to a city like Sydney or Brisbane, and the generally lower cost of living out here. I'm sure in NYC you'd get ridiculous prices on electricity!