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Electronic clocks in applicances?

K

Ken Taylor

Jan 1, 1970
0
Chris said:
Trevor Wilson wrote:



Yes if your TV only uses 0.15W that is fine. If your TV + set top box uses
40 Watts all the time, as I measured in my parent's house, then that is
worth thinking about. (The TV by itself was about 10W switched off with
the remote.) Even if you don't give a rat's arse about the environment,
40W is roughly $35 a year, so if you keep your TV + set top box for say 10
years then it should be worth spending at least $100 to buy ones more like
the one you mentioned above, even when you factor in the interest rate that
you could get on that $100. Personally I don't like the waste of resources
either but most people don't care about that.

And yes I agree with you that the solar water heater is a good idea and the
compact fluoros too.

Chris
I can agree with what you're saying but I think your priorities are
wrong. When you're travelling at 100km/hr towards a cliff you don't
check that rear-view mirror is correctly adjusted. :)

Seriously, if, as has been said elsewhere, standby power consumption is
coming down to about 1% of the present amount, then we're heading in the
right direction (ie. cliff being averted). This is a good thing. But the
heating thing is still the major area.

Cheers.

Ken
 
D

David L. Jones

Jan 1, 1970
0
The said:
Hi all,

I have heard it before that even the digital clock on DVD players
or microwave ovens can add up to a fair bit of power. How much power
do they typically draw? Are there any plans by major manufacturers to
reduce that?

Yes, it can add up.
Latent power consumption for typical applinces can range from say one
watt to tens of watts depending on what it is and how well it is
designed. A lot of the time people will simply leave stuff on instead
of turning it off. DVD players and Set Top Boxes for instance simply
get left on and the TV switched to standby mode.

There are several manufacturers who advertise their stuff as having
"low standby power", so I guess they are at least thinking about it. My
Samsung VCR was advertisd like that as a big feature, although I'm not
sure of it's actual latent power consumption.

The average home can easily have a few dozen standby power appliances,
so it does all add up. Some of it's needed and some of it's not.
I've got my entire entertainment system powered through one
conveniently located power point, so I switch it all off at the wall
when not being used. It's actually very convenient because everything
powers back up to exactly where it left off before. Using the remotes
(all 4 of them) just to switch everything into standby mode would take
longer and be more hassle!

Check out the Steve Ciarcia article on the issue for how much his home
takes - ouch! :
http://www.circuitcellar.com/library/priorityinterrupt/172.htm

Dave :)
 
G

Greig Corlett

Jan 1, 1970
0
Trevor Wilson said:
**Yep. I've heard the same bullshit.

How much power

**About the same amount in one year as a two bar heater will use in a few
hours. Or as much in one week as a few halogen downlights will use in one
hour.

Are there any plans by major manufacturers to

**Yep. There are no plans to get consumers to switch to Solar hot water,
however, which would REALLY reduce power consumption. Of to get people to
wear an extra sweater during the Winter, instead of running that central
heating. Or to choose more efficient appliances (better air conditioners,
'fridges, etc) instead of buggering around with inconsequential things.

Education and common sense will reduce electricity consumption for more
efficiently that turning off a DVD player.
Coming from an industrial background in New Zealand I see this problem all
the time.

I often wonder how people measure this power used by devices in standby.
Most of the portable meters that are available are not sensitive enough to
measure down to under 1W nor are they capable of measuring out of phase or
true power.

Let me introduce you people to a little problem known as bad power factor.

In Industry We actually can turn on water heating and capacitors to reduce
the total load on the system.

An even bigger factor to be considered is the bad power factor of our power
systems caused by switchmode power supplies used in modern electronics and
heavy industrial motors. A bad power factor is where an appliance draws AC
current that is not in sync with the voltage. This causes high apparent
currents which if we relate back to your TV, the cheaper meters are not
true RMS this means that if the meter was to read the power drawn by the TV.
It would appear as 10w on the meter but it's true power could be only about
0.2 - 0.5w. I agree that solar power hot water would reduce total load on
our system but we need some large resistance loads to reduce our terrible
power factor.

As far as the supply authorities are concerned this power factor is a way
for them to get more money out of industry. it has only recently been
enforced that in a new industrial installation that power factor correction
units be put in to reduce the load. but the real problem is that as we get
more sophisticated electronics using swiutchmode supplies and as air
conditioning units become popular in our homes the combined effect of these
loads cause our power supply to have a bad power factor.

The effects of a bad power factor is first of all the top and bottom of the
ac supply sine wave is flattened. this in effect is a dc point on the
supply. this causes motors and transformers to become less efficient as
much as 60% of their maximum capacity. the main effects are excessive
heating in their windings.

If I take for example an industrial welder on it's own it draws a maximum
current of 50A but if we put a capacitor across it's supply for power factor
correction we can reduce it's current to 30A. so as you can see by putting
this correction in place we can save 40% energy in this case.

So why don't companies put in this feature it's because it is not a well
known effect and the average person doesn't understand, Another thing mains
rated AC capacitors are expensive. So if the consumer doesn't know it has a
negative effect on the supply why bother.

in my opinion as our supply load reduices the line capacity we need to
install power factor correction on our supply.

In a nutshell motors and appliances peak in their current draw before the
voltage is at a maximum.
power factor correction capacitors draw current after the voltage maximum.
so if we can measure the amount the voltage and current are different we can
correct it by placing capacitors in the circuit.

i could keep giong on about the effects but i will leave it at this.
 
G

Greigcorlett

Jan 1, 1970
0
Agent " 86 " ® said:
I hope your not a 12 oclock flasher !!!!!!!!!!

one hell of a misconception

news flash

Halogen lights are worse than normal lights. people think that because they
are low voltage they are efficient. Have you seen how hot they get and how
hot the transformers get. This is all waste energy. all halogen light
fittings are made of high temp ceramic and the cables are made of high temp
insulation because they get so hot. when installing them in a ceiling there
the manufacture specifies 150mm diameter with no insulation compared with
100mm for a standard 240v recess downlight. these are things that we aren't
told when we buy these things. I wonder how many people who are over fussed
on energy saving put these lights in because they think they are efficient.
 
K

Ken Taylor

Jan 1, 1970
0
Greigcorlett said:
one hell of a misconception

news flash

Halogen lights are worse than normal lights. people think that because they
are low voltage they are efficient. Have you seen how hot they get and how
hot the transformers get. This is all waste energy. all halogen light
fittings are made of high temp ceramic and the cables are made of high temp
insulation because they get so hot. when installing them in a ceiling there
the manufacture specifies 150mm diameter with no insulation compared with
100mm for a standard 240v recess downlight. these are things that we aren't
told when we buy these things. I wonder how many people who are over fussed
on energy saving put these lights in because they think they are efficient.
Who had the misconception in what you replied to?

Cheers.

Ken
 
T

Trevor Wilson

Jan 1, 1970
0
Greigcorlett said:
one hell of a misconception

news flash

Halogen lights are worse than normal lights. people think that because
they are low voltage they are efficient.

**They ARE more efficient than regular incanescent. Not by a huge amount
though.

Have you seen how hot they get and how
hot the transformers get.

**Two words: 'Electronic transformers'. Additionally, a transformer SHOULD
incur a penalty of around 10-20% at most. That still puts halogens higher
than incandescent in the efficiency stakes. Running lots of halogens from a
single transformer will increase efficiency still further.

This is all waste energy. all halogen light
fittings are made of high temp ceramic and the cables are made of high
temp insulation because they get so hot. when installing them in a
ceiling there the manufacture specifies 150mm diameter with no insulation
compared with 100mm for a standard 240v recess downlight. these are
things that we aren't told when we buy these things. I wonder how many
people who are over fussed on energy saving put these lights in because
they think they are efficient.

**They buy them because they look trendy. People don't care about
efficiency. If they did, then they'd be using Solar heating for their hot
water.
 
A

Agent \ 86 \ ®

Jan 1, 1970
0
Trevor Wilson said:
**They ARE more efficient than regular incanescent. Not by a huge amount
though.

Have you seen how hot they get and how

**Two words: 'Electronic transformers'. Additionally, a transformer SHOULD
incur a penalty of around 10-20% at most. That still puts halogens higher
than incandescent in the efficiency stakes. Running lots of halogens from a
single transformer will increase efficiency still further.

Transformers AC that is are far more efficient than your stating , normally
95-98 percent
 
T

Trevor Wilson

Jan 1, 1970
0
Agent " 86 " ® said:
Transformers AC that is are far more efficient than your stating ,
normally
95-98 percent

**Depends on the transformer. Go talk to a transformer manufacturer and get
back to me. Some, cheap, crappy halogen transformers are probably no better
than 70% efficient (my seat-of-the-pants guesstimate).
 
M

Mark Harriss

Jan 1, 1970
0
Trevor said:
**Depends on the transformer. Go talk to a transformer manufacturer and get
back to me. Some, cheap, crappy halogen transformers are probably no better
than 70% efficient (my seat-of-the-pants guesstimate).

Worst case 77%, best case 93% with most around 86% efficiency. 500GW Hrs
are estimated to be wasted per year in Australia.
 
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