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| David... |
 Posted: Tue Nov 03, 2009 12:03 pm |
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"William Sommerwerck" <grizzledgeezer at (no spam) comcast.net> wrote in
message news:hcn3ak$4fj$1 at (no spam) news.eternal-september.org...
[quote]Its been pointed that you don't really need a watt or
watt-hour meter to
save money -- you just turn off things you're not using.
This is not altogether true.
My electric bill was ridiculous, so I started checking.
I'd been too lazy to
regularly turn off my A/V system's equipment, which
includes a number of
vampire devices.
I was surprised to discover that the Parasound controller
pulled 30VA, even
when not turned on. And a Lexicon CP-3plus drew 20VA,
simply in standby. As
I rarely use it, I turned the standby switch to "off".
Most of the vampire devices are items I don't use
regularly. I'm going to
move them to their own strip, so that they will always be
off, except when
actually being used.
[/quote]
I have just two comments on this:
1) If you are a residence, you are metered and billed by
watts (re: real power) rather than volt*amps. Measure the
watts to see the power consumption that actually is part of
your billing.
2) If you live in an area that requires heating your house
for a majority of a year, the power dissipated is added to
the heating of your house during the heating season and
reduces energy consumption from the furnace energy supplier.
The power is not wasted in this situation. This fact is
rarely considered by the media.
David |
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| Phil Hobbs... |
| Posted: Tue Nov 03, 2009 7:42 pm |
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William Sommerwerck wrote:
[quote]Your electric meter measures watts, not VA. If you know the power
factor, you can convert these VA measurements to watts and eventually
to your cost of electricity. The kill-a-watt meter shows both VA and
watts (as well as PF).
My understanding was that the watt-hour meter actually measure VA-hours. I
asked the electric company once, and that said that was the case. But I
wasn't speaking with an engineer.
That's VARs, not VA-hours. For 'volt-ampere reactive'.[/quote]
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net |
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| William Sommerwerck... |
| Posted: Tue Nov 03, 2009 8:35 pm |
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[quote]My understanding was that the watt-hour meter actually measure VA-hours.
I
asked the electric company once, and that said that was the case. But I
wasn't speaking with an engineer.
That's VARs, not VA-hours. For 'volt-ampere reactive'.
[/quote]
If you can have watt-hours, you can have VA-hours. Both are units of energy.
Is VAR a unit of energy? No, it's a unit of (reactive) power. Energy and
power are not the same. |
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| Van Chocstraw... |
| Posted: Tue Nov 03, 2009 10:00 pm |
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William Sommerwerck wrote:
[quote]Its been pointed that you don't really need a watt or watt-hour meter to
save money -- you just turn off things you're not using.
This is not altogether true.
My electric bill was ridiculous, so I started checking. I'd been too lazy to
regularly turn off my A/V system's equipment, which includes a number of
vampire devices.
I was surprised to discover that the Parasound controller pulled 30VA, even
when not turned on. And a Lexicon CP-3plus drew 20VA, simply in standby. As
I rarely use it, I turned the standby switch to "off".
Most of the vampire devices are items I don't use regularly. I'm going to
move them to their own strip, so that they will always be off, except when
actually being used.
------
"We already know the answers -- we just haven't asked the right
questions." -- Edwin Land
[/quote]
I went from 400kwh a month to 200kwh but putting all vampire devices on
power strips and shutting things off that are not needed. My oil burner
alone takes 100kwh a month until I switched to pellets and wood boiler
when it's real cold. I like free hot water. |
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| Geoffrey S. Mendelson... |
| Posted: Wed Nov 04, 2009 10:09 am |
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Ron wrote:
[quote]I once knew someone who always switched the wall sockets off when not is
use to prevent the electrickery flowing out of the open socket.
[/quote]
I was told by someone that they were worried about the radiation from
their (receive only) satellite dish.
Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel gsm at (no spam) mendelson.com N3OWJ/4X1GM |
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| Phil Hobbs... |
| Posted: Wed Nov 04, 2009 11:42 am |
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Guest
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William Sommerwerck wrote:
[quote]My understanding was that the watt-hour meter actually measure VA-hours.
I
asked the electric company once, and that said that was the case. But I
wasn't speaking with an engineer.
That's VARs, not VA-hours. For 'volt-ampere reactive'.
If you can have watt-hours, you can have VA-hours. Both are units of energy.
Is VAR a unit of energy? No, it's a unit of (reactive) power. Energy and
power are not the same.
Yes, of course. But a VA-hour is a meaningless unit unless you know the[/quote]
power factor--real power costs money and fuel, whereas (apart from
transmission losses) reactive power just sloshes back and forth cycle by
cycle. That's why multiplying it by any period of time longer than a
cycle is meaningless.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net |
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| D Yuniskis... |
| Posted: Wed Nov 04, 2009 1:36 pm |
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Phil Hobbs wrote:
[quote]Yes, of course. But a VA-hour is a meaningless unit unless you know the
power factor--real power costs money and fuel, whereas (apart from
transmission losses) reactive power just sloshes back and forth cycle by
[/quote]
This one is a keeper -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^
;-)
[quote]cycle. That's why multiplying it by any period of time longer than a
cycle is meaningless.[/quote] |
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| David Nebenzahl... |
| Posted: Wed Nov 04, 2009 2:28 pm |
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On 11/4/2009 10:36 AM D Yuniskis spake thus:
[quote]Phil Hobbs wrote:
Yes, of course. But a VA-hour is a meaningless unit unless you know the
power factor--real power costs money and fuel, whereas (apart from
transmission losses) reactive power just sloshes back and forth cycle by
This one is a keeper -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^
;-)
cycle. That's why multiplying it by any period of time longer than a
cycle is meaningless.
[/quote]
Ah, so electricity really *is* like water, eh? (Volts = pressure, amps =
flow.)
--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?
- harvested from Usenet |
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| Ron... |
| Posted: Wed Nov 04, 2009 2:56 pm |
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David Nebenzahl wrote:
[quote]On 11/4/2009 10:36 AM D Yuniskis spake thus:
Phil Hobbs wrote:
Yes, of course. But a VA-hour is a meaningless unit unless you know
the power factor--real power costs money and fuel, whereas (apart
from transmission losses) reactive power just sloshes back and forth
cycle by
This one is a keeper -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^
;-)
cycle. That's why multiplying it by any period of time longer than a
cycle is meaningless.
Ah, so electricity really *is* like water, eh? (Volts = pressure, amps =
flow.)
I once knew someone who always switched the wall sockets off when not is[/quote]
use to prevent the electrickery flowing out of the open socket.
Ron |
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| Ron... |
| Posted: Wed Nov 04, 2009 3:33 pm |
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Geoffrey S. Mendelson wrote:
[quote]Ron wrote:
I once knew someone who always switched the wall sockets off when not is
use to prevent the electrickery flowing out of the open socket.
I was told by someone that they were worried about the radiation from
their (receive only) satellite dish.
Geoff.
Thats why they used to come with instructions for making a tinfoil hat[/quote] |
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| Jeff Layman... |
| Posted: Wed Nov 04, 2009 5:16 pm |
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N_Cook wrote:
[quote]
I bought a set-top box (UK Freeview) and thought to myself
"hang on a bit the box is as warm with green LED on as on red standby"
I measured consumed watts in both states and standby is 80 percent of the
on state. I put in a hard on/off switch , data held in EEProm or whatever
and no difference in function except programme info pages takes a couple
of minutes to gather
[/quote]
What is meant by "standby"? You may think you know (as I thought I did,
too), but it isn't that simple. See here:
http://arstechnica.com/gadgets/news/2009/02/sony-lcd-exceeds-energy-star-power-draw-75-of-time.ars
It's not just Sony. I queried Panasonic about the regular clicking from my
LCD TV, even when it was in "Standby" mode, and also the less-than-green
readings I was getting from a power meter attached to it (15w in standby,
and 30w when it clicked. I do not know what the power factor of the TV is,
so do not know how these figures correlate with Panasonic's stated standby
consumption of 0.3w, but they don't seem very different from those reported
with the Sony). This was their reply:
"In response, I would advise that first please ensure the SETUP menu option
for “auto search in standby” is switched off. (this is in the “System
Update” SETUP menu option.
Turning off this option will also stop intermittent clicking from the TV
that are caused as the internal PSU relays are turned on to allow the
Freeview decoder to work for software updating.
2.) Please note that the set takes approximately 2 minutes for all the PSU
relays to click off and so the power will only read 0.5W after this time.
3.) Ensure that the power meter used can read the power factor of the unit
required to calculate AC power and is using this to calculate power.
4.) Ensure the meter is capable of accurately reading 0.5W; many meters
cannot go this low. Please refer to the meter’s specification."
That reply was open and very helpful, but (a) "auto search in standby" is
the default condition (b) there is no mention of this in the manual (c) I
still do not know how often the TV goes into auto search mode, for how long,
and what the actual power consumption is in this mode.
I have now taken to switching off at the plug when the TV is not in use.
Info on the DTG pages let me know when to leave the TV in standby/autosearch
for an update.
It makes me wonder just how accurate many other low consumption "standby"
figures are.
--
Jeff |
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| AZ Nomad... |
| Posted: Wed Nov 04, 2009 6:13 pm |
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On Wed, 4 Nov 2009 22:16:35 -0000, Jeff Layman <jmlayman at (no spam) invalid.invalid> wrote:
[quote]N_Cook wrote:
I bought a set-top box (UK Freeview) and thought to myself
"hang on a bit the box is as warm with green LED on as on red standby"
I measured consumed watts in both states and standby is 80 percent of the
on state. I put in a hard on/off switch , data held in EEProm or whatever
and no difference in function except programme info pages takes a couple
of minutes to gather
What is meant by "standby"? You may think you know (as I thought I did,
too), but it isn't that simple. See here:
http://arstechnica.com/gadgets/news/2009/02/sony-lcd-exceeds-energy-star-power-draw-75-of-time.ars
It's not just Sony. I queried Panasonic about the regular clicking from my
LCD TV, even when it was in "Standby" mode, and also the less-than-green
readings I was getting from a power meter attached to it (15w in standby,
and 30w when it clicked. I do not know what the power factor of the TV is,
so do not know how these figures correlate with Panasonic's stated standby
consumption of 0.3w, but they don't seem very different from those reported
with the Sony). This was their reply:
[/quote]
that's impressive. I just took my killowatt from storage and measured a few
devices. 50" panasonic plasma: on 340watts, off less than 1. 32" polaroid lcd:
130 Watts on, less than 1 off.
diskless computer for mythtv remote (1.8ghz amd64, 2G ram), 25 watts on, no
standby mode. Scientific Atlanta HD cable box, 20 watts on/standby.
No surprises. I knew the cable box was a pig, about the same as a computer
left running 24x7. |
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| David Nebenzahl... |
| Posted: Wed Nov 04, 2009 6:55 pm |
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On 11/4/2009 11:56 AM Ron spake thus:
[quote]David Nebenzahl wrote:
Ah, so electricity really *is* like water, eh? (Volts = pressure, amps =
flow.)
I once knew someone who always switched the wall sockets off when not is
use to prevent the electrickery flowing out of the open socket.
[/quote]
Don't laugh; way back when, they (you know, "they" who put light bulbs
inside refrigerators and such) used to sell outlet covers for nervous
customers worried about just that.
--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?
- harvested from Usenet |
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| David Brodbeck... |
| Posted: Sat Nov 07, 2009 10:27 pm |
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N_Cook wrote:
[quote]I bought a set-top box (UK Freeview) and thought to myself
"hang on a bit the box is as warm with green LED on as on red standby"
I measured consumed watts in both states and standby is 80 percent of the on
state. I put in a hard on/off switch , data held in EEProm or whatever and
no difference in function except programme info pages takes a couple of
minutes to gather
[/quote]
I checked my VCR/DVD player one day and found that it drew exactly the
same amount of power when "off" as it did when "on". The power button
was essentially just a placebo. |
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