[ed.howell]

Hi guys,


A friend of mine just bought a Panasonic EDTV plasma for his new house and he is not wondering if and how much of an affect it will have on his electric bills. I told him probably not much but I am not sure since I do not own one and seek some expert advice.


Thanks in advance for your help.


Ed

 

[hiker]

About one year ago I put a power meter on my 42pwd6uy and it averaged about 200 watts. Do the math for an estimate.

 

[ed.howell]

Thanks,


What does that compare to with some of the other appliances around the house?

 

[JuiceRocket]

I haven't seen a change in my electric bill with the addition of our plasma.


-JR

 

[mooneydriver]

About three regular (incandescent) light bulbs or one halogen torchiere. Power is sold by kilowatt-hour, so assuming your friend uses the TV five hours a day, he'll use approximately one kilowatt-hour per day. Find out what your municipality charges per kwh (listed on your utility bill) and multiply that number by thirty to find out what it will cost per month.

 

[SaltiDawg]

Quote:

Originally posted by mooneydriver ...Find out what your municipality charges per kwh (listed on your utility bill) and multiply that number by thirty to find out what it will cost per month.

And to determine the effect on your frien's bill, do the same calculation for the old set it replaced and subtract that value. (Assuming the plasma is a replacement.

 

[lifo]

200 watts is slightly less than a computer's power supply.

 

[72Anthony]

lifo,


That is the ouput if the power supply...It actually draws more, all that heat it gives off is a by product of transforming AC into DC.

 

[Ross in Toronto]

Quote:

Originally posted by 72Anthony lifo, That is the ouput if the power supply...It actually draws more, all that heat it gives off is a by product of transforming AC into DC.

When UL in the 'States and CSA in Canada certify the AC current ratings on transformers / power supplies, I would expect that would represent the total power draw, including the AC / DC conversion heat. Having said this, if it doesn't include this additional current draw, it is probably quite low, most likely smaller than the minute-to-minute variation in power draw from the panel itself...? I'm only speculating.


As for the cost of running the panel... my 50" Pio draws 400W including the media receiver. My receiver pulls another 600 W or so. Toss in the DVD player, powered subwoofer and HD STB, and I'll round it up to 1200 W total.


Total cost per month = (cost of electricy per kWh) x (total watts) x (hours of use per day) / 1000 (to convert W to kW) x 30 days.


So, if the cost of electricity is $0.15 per kWh, and I use the system on average 3 hours a day, I come up with $16.20 per month. That's probably on the high side since I doubt I get 21 hours a week of TV use (more like 10, max).


Here's a nice summary of how much power various appliances use (and their cost based on a $0.068 kWh):

http://www.city.ames.ia.us/ElectricW...appliances.htm


My 3 hours per day of plasma + receiver + DVD is at the low end of a small (room sized) air conditioner, and far, far less than central air. It also falls at the high end of a food freezer, and right in the middle of an intermittent (probably AC) furnace fan.


Of course, if the average per day is 2 hours, the total consumption is less!


I work in the Ontario electrical industry. If you're in Ontario, New York state or Michigan, please leave your plasmas on 24 / 7 (and especially your air conditioners).


Thanks,

Ross

 

[Mike52]

Hey! I already have to pay for my father-in-laws' retirement from Consumers Energy. So I can't afford to pay yours too.

How about buying more lottery tickets to help pay for my retirement (teacher)?


Mike52

 

[tws1972]

There has been NO NOTICEABLE difference in my electric bill. I would say it probably just comes out to some cents per month.

 

[SaltiDawg]

Quote:

Originally posted by Ross in Toronto ... My receiver pulls another 600 W or so. ...

Ross,


While your Receiver may be rated at 600 W or so - it will not draw that even when the Cannons are going Off while you're playing the 1812 Overture at max volume. In a reasonable sized room you are almost assuredly drawing less than 10 Watts for your audio.


Many TV sets have integral audio sytems and speakers that are rated at 20 or 25 Watts. While the fidelity would be terrible, you would find the audio level deafening if you two-blocked the set at 25 Watts.


Edit : The link you provided for finding "typical" power demand and usage info suggests for a Stereo the Wattage is about thirty Watts - and I would suggest that is quite high for a home stereo.

 

[Ross in Toronto]

SaltiDawg,


Thanks for pointing out that error in my calculations. The cost, therefore, is basically half what I calculated.


There is consideration in Ontario of moving to interval metering for households. This basically means the Utility keeps track of not just how many kWh you are using, but when (what time of day). We have a daily fluctuation in (wholesale) electricity prices in Ontario that can range from 3.5 cents per kWh in the middle of the night to 10 cents in mid-day (that doesn't include transmission costs, etc.). http://www.iemo.com/imoweb/marketdata/marketToday.asp


Hence the cost of running the system will also be a function of when you use it.


Ross

 

[bgbem]

I put a meter on my ED Panny today. It took 3 hours 45 minutes to use one kwh.

One thing I found interesting. When I first turned the Panny on, the tv was drawing 360 watts. As it warmed up, it started drawing less. A few hours later, it was drawing between 180 and 290 watts. It was using about 2.5 amps. With the tv shutoff, it was using 17 watts.

 

[Ross in Toronto]

bgbem,


How do those numbers compared to the power consumption quoted in your display's user manual? 17 watts for stand-by / shut off seem high...? My 50" Pio' user manual says 363 W powered on, but only 0.3 W on stand-by... but I have not measured the consumption directly.


It's interesting that its power consumption peaks at the beginning and drops as it warms up. I suspect this is somehow related to the voltage difference between the address electrode and display electrode. When the gas in the cells is cold, it is reasonable to assume its electrical conductivity is lower, hence a higher discharge voltage is needed to achieve the same discharge current (the latter quantity being the 'spark' that generates the UV photons that in turn fire the phosphors coating the cell.) As the gas warms up, less discharge voltage is needed to achieve the same discharge current. The internal power supply (fed by a constant input voltage, of course) has to draw more current out of your wall socket to achieve a higher discharge voltage for the constant discharge current.


This is 100% pure speculation on my part. I don't know for sure what is going on. I'm not even certain if there is an appreciable variation in the gas conductivity for the few dozen degrees C variation we're taking about here.


My engineering degree is NOT in electrical engineering, but I know enough to be dangerous.


Ross

 

[optivity]

Quote:

Originally posted by ed.howell Hi guys, A friend of mine just bought a Panasonic EDTV plasma for his new house and he is not wondering if and how much of an affect it will have on his electric bills. I told him probably not much but I am not sure since I do not own one and seek some expert advice. Thanks in advance for your help. Ed

My advice to your friend is if he is concerned about his electric bill he should not be buying a Plasma TV. It's nothing more than an expensive "toy!"

 

[nuke]

About the same as other TV's in the same size range.