Lets talk about electric consumption...

[Mark42]

A 15 watt florescent bulb will burn for about 66.66 hours on one killowatt of electricity. <br /><br />If one kilowatt hour costs 20 cents, then 66.66 hours of light will cost only 20 cents. <br /><br />Right or wrong?

 

[crab bait]

Re: Lets talk about electric consumption...

MAN,, run outta projects to do ,or what..??..

 

[chuckz]

Re: Lets talk about electric consumption...

Right for an incandescent bulb, wrong for a flourescent bulb. The efficiency of the flourescent bulb is less than 100%. However, flourescent bulbs give you more light output than an equivalent incandescent bulb becuase a lot of energy is wasted as heat in the incandescent bulb.

 

[JB]

Re: Lets talk about electric consumption...

Yes, Mark. Your math is accurate.

 

[ZmOz]

Re: Lets talk about electric consumption...

Originally posted by L.I. Chuck:<br /> Right for an incandescent bulb, wrong for a flourescent bulb.

Depends whether it's a compact fluorescent or a standard tube. If you have a 25 watt shop light, for example, the tube will use 25 watts but the entire fixture will use more than that. On a compact fluorescent, however, they are rated by what the ballast uses...so a 15 watt CF bulb only uses 15 watts total.

 

[jlshields]

Re: Lets talk about electric consumption...

20 cents per kwh! Man that's expensive. Here in central Indiana it runs less than 8 cents, 7.91 to be exact and we get darn reliable service too.

 

[Mark42]

Re: Lets talk about electric consumption...

ZmOz, are the compact flourescent bulbs the ones that screw in to replace standard incandescent bulbs?<br /><br />JlShields, I think we pay between 9 and 12 cents a kwh, I used 20 for round numbers.<br /><br />Thanks JB!<br /><br />Bottom line is leaving a 15 watt compact flourescent bulb on as a night light is not really wasteful because it is rather cheap to operate.

 

[ZmOz]

Re: Lets talk about electric consumption...

Originally posted by Mark42:<br /> ZmOz, are the compact flourescent bulbs the ones that screw in to replace standard incandescent bulbs?

Yep.<br /><br />

Originally posted by Mark42:<br />Bottom line is leaving a 15 watt compact flourescent bulb on as a night light is not really wasteful because it is rather cheap to operate.

Yep again. Even at 10c/KW, a 15 watt CF bulb only cost $0.0015 per hour. Even a plain old 60 watt bulb only cost $0.006 per hour. Compact fluorescents are hardly worth the initial investment unless you have a light that's on 24/7.

 

[Bob_VT]

Re: Lets talk about electric consumption...

Flourescent bulbs use a ballast (at least the long ones do).... does that suck up any power in addition to the bulb when in use??

 

[chuckz]

Re: Lets talk about electric consumption...

Yes, the ballast is a transformer, it's not 100% efficient.<br /><br />If it generates heat, it's dissipating power.

 

[ndemge]

Re: Lets talk about electric consumption...

All right, Lightbulb conversations in the Summer time ! I thought I had to wait for winter for this <br /><br /><br />..... I keep a 14 watt floresent in the garage on 24/7, no switch on the wall, so if I walk in at night, I have to stumble over things to hit the pull string, so just put that light in and leave it on.

 

[ZmOz]

Re: Lets talk about electric consumption...

Originally posted by NoelMG:<br /> ..... I keep a 14 watt floresent in the garage on 24/7, no switch on the wall, so if I walk in at night, I have to stumble over things to hit the pull string, so just put that light in and leave it on.

I do the exact same thing.

 

[Paul Moir]

Re: Lets talk about electric consumption...

The heating season lasts 7 or 8 months here. So you get to use your energy again as heat for the house. Since oil is about half the cost of electric heat, for those 7 or 8 months you get 5c of your 10c back as heat, which averages out to about 3c off each KW spent over the year.<br />Somebody asked me once why people with electric heat bother shut off their lights at night in the winter.