Frugal and Energy Efficient Living

Fumesucker

(45,851 posts)

20. Sorry, you buy power by the kilo*watt* hour so it's watts you pay for

Sun Dec 1, 2013, 05:44 AM

Dec 2013

Or more accurately watt-hours which is amps x volts x time. A kilowatt hour used at 100% efficiency will run a 1000 watt heater for one hour.

120 volts at ten amps is the same amount of power as 240 volts at five amps and will provide the same amount of heat.

Higher voltage does have a slight advantage since smaller diameter wire is needed to carry a given amount of watts, to get 1000 watts at 12 volts for instance requires 1000/12 or 83.33 amps which is going to take some roughly pencil sized copper conductors to carry reasonably efficiently.

A 12 volt electric heater that uses 83.3 amps is going to provide as much heat as a 120 volt heater that uses 8.33 amps, the wire connecting the heater though needs to be a little more than three times as large in diameter (the square root of 10).

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Costs to run an electric space heater [View all] Kaleva Nov 2013 OP

Until it gets down below 20 degrees outside, I don't even turn on central heat... hlthe2b Nov 2013 #1

I've got 2 space heaters going and the house temp is maintaining at 54 degrees. Kaleva Nov 2013 #2

I've always thought Norfolk pines were breathtaking IrishAyes Dec 2013 #22

I find Norfolk Island Pines very difficult...Even when I lived for a while in the South with natural hlthe2b Dec 2013 #25

Well, I've got a green thumb, and I could overwinter them; but right now I can't afford to. IrishAyes Dec 2013 #27

There are a couple of things we rarely use on the boat because of huge energy consumption. cbayer Nov 2013 #3

I did not know that the Ecofan worked on gas stoves. Kaleva Nov 2013 #5

You just need a flat surface to put it on. cbayer Nov 2013 #7

I had thought of putting in a vent free wall mounted 10k btu/h space heater... Kaleva Nov 2013 #8

I bought one of those; never thought about putting it on a cast iron pan though. IrishAyes Dec 2013 #23

I think it would make it kick on sooner and would distribute the heat cbayer Dec 2013 #26

Have you tried the flower pot/candle setup yet? Curmudgeoness Nov 2013 #4

I don't think the flower pot candle setup would provide enough heat Kaleva Nov 2013 #6

I see wattage discussed here, but not voltage -VOLTAGE is critical. ConcernedCanuk Nov 2013 #9

Very few, if any, have 240 outlets distributed throughout their homes. Kaleva Nov 2013 #10

Most Kitchen stoves and hot water heaters are 240 ConcernedCanuk Nov 2013 #12

The electrical code must be different where you live. Kaleva Nov 2013 #13

ummm - it's NOT to code, and I don't care. ConcernedCanuk Nov 2013 #14

I wouldn't recommend your method to others though Kaleva Nov 2013 #16

Yep, exactly, I used to work as an electrician. Code wise, it's a big NO NO. n/t RKP5637 Nov 2013 #18

I realize that, BUT ConcernedCanuk Dec 2013 #28

This message was self-deleted by its author RKP5637 Dec 2013 #30

Yep, sometimes a license means nothing about the correctness and quality of the work. n/t RKP5637 Dec 2013 #31

That's the same one I have. It's amazing. cbayer Nov 2013 #11

Here they are in action! ConcernedCanuk Dec 2013 #29

Perfect! cbayer Dec 2013 #32

Sorry, you buy power by the kilo*watt* hour so it's watts you pay for Fumesucker Dec 2013 #20

I just calculated my kwh charges here (Colorado)--boy, if you are paying .20c kwh, that's high hlthe2b Nov 2013 #15

Cost here is about .06/kwh, all elec. house, never had one before, but that's what RKP5637 Nov 2013 #19

Thanks for mentioning this! Watts = Watts. I think sometimes people get mislead RKP5637 Nov 2013 #17

In my area it costs about $0.50/day (8 hours) to run a space heater. n/t lumberjack_jeff Dec 2013 #21

Often, codes can be ignored. IrishAyes Dec 2013 #24