Switch off at the socket?

On 15/09/09 08:54, Gordon Henderson wrote:

http://www.inference.phy.cam.ac.uk/sustainable/charger/

I read that and started thinking the 5000W per person figure was a
confusion between power units and energy units, and assuming it meant
5000Wh per person per day, but I decided I'd best check the numbers
before possibly inserting foot into mouth ...

According to the International Energy Association figures for 2001
the total UK energy consumption was 262,186,000 tonnes of oil equivalent

or about 4.3 tonnes of oil per person

or 180 Gigajoules per person

so dividing by 8760 hours that *did* equate to a continuous 5.7kW per
person. Granted some of that will contribute to exported goods and
services, but equally our imports will contribute to other countries'
consumption figures so it's difficult to adjustment for that.

Still barely makes it worthwhile unplugging idle phone chargers though,
most of that power is consumed on our behalf, not directly by us.

On Sep 15, 11:16*am, "Zimmy" wrote:
"Norman Wells" wrote in message

...



Zimmy wrote:
"Norman Wells" wrote in message
...

However, he ignores the fact that he's also losing 45 watts of heat.
To keep his house at exactly the same temperature, an extra 45 watts
of heat need to be pumped out by whatever heating system he has, for
as much of the year as he needs any heating at all. *Admittedly,
that may be a bit cheaper if it's gas-fired, but it's still the same
amount of energy, so it's unlikely to have a huge impact on climate
change.

You are assuming that those 45W of electricity are converted to 45W
of heat with 100% efficiency which is clearly not true.

Where else do you think it goes?

Hmm, maybe powering the standby circuitry, IR receivers, etc?

Which is ultimately turned into heat.

MBQ

Zimmy wrote:
"Norman Wells" wrote in message
...
Zimmy wrote:
"Norman Wells" wrote in message
...

However, he ignores the fact that he's also losing 45 watts of
heat. To keep his house at exactly the same temperature, an extra
45 watts of heat need to be pumped out by whatever heating system
he has, for as much of the year as he needs any heating at all.
Admittedly, that may be a bit cheaper if it's gas-fired, but it's
still the same amount of energy, so it's unlikely to have a huge
impact on climate change.

You are assuming that those 45W of electricity are converted to 45W
of heat with 100% efficiency which is clearly not true.

Where else do you think it goes?


Hmm, maybe powering the standby circuitry, IR receivers, etc?

What does it do while it's doing all that, and where do you think it goes
afterwards?

"Dave Plowman (News)" wrote in message
...
In article ,
Norman Wells wrote:
You are assuming that those 45W of electricity are converted to 45W
of heat with 100% efficiency which is clearly not true.

Where else do you think it goes?

I suppose those LEDs produce some light? ;-)

Which are absorbed by the walls and furniture, unless you leave your
curtains open at night.

--
Max Demian

On Sep 15, 11:28*am, Andy Burns wrote:
On 15/09/09 08:54, Gordon Henderson wrote:

http://www.inference.phy.cam.ac.uk/sustainable/charger/

I read that and started thinking the 5000W per person figure was a
confusion between power units and energy units, and assuming it meant
5000Wh per person per day, but I decided I'd best check the numbers
before possibly inserting foot into mouth ...

According to the International Energy Association figures for 2001
the total UK energy consumption was 262,186,000 tonnes of oil equivalent

or about 4.3 tonnes of oil per person

or 180 Gigajoules per person

so dividing by 8760 hours that *did* equate to a continuous 5.7kW per
person. Granted some of that will contribute to exported goods and
services, but equally our imports will contribute to other countries'
consumption figures so it's difficult to adjustment for that.

Still barely makes it worthwhile unplugging idle phone chargers though,
most of that power is consumed on our behalf, not directly by us.

Indeed. As the saying goes, 100% of bugger all is still bugger all.
OTOH, even just 20% of something larger like unneccessary nightime
illumination in shops may be worthwhile. i don't know the exact
figures but you see what I mean.

MBQ

On 15/09/09 11:16, Zimmy wrote:

"Norman Wells" wrote:

Where else do you think it goes?

Hmm, maybe powering the standby circuitry, IR receivers, etc?

And where do you think it ENDS UP? Pretty much the only energy that
doesn't contribute to heating the house is the light and sound that that
makes it through the windows and walls.

"Dave Plowman (News)" wrote in message
...

You know of a VCR etc which can do a pre-programmed recording when powered
down at the socket?

A media centre PC (laptop) will do that.
They will even wakeup from hibernation and do a recording and then hibernate
again.

On Tue, 15 Sep 2009 09:39:13 +0100, "Norman Wells"
wrote:

However, he ignores the fact that he's also losing 45 watts of heat. To
keep his house at exactly the same temperature, an extra 45 watts of heat
need to be pumped out by whatever heating system he has, for as much of the
year as he needs any heating at all. Admittedly, that may be a bit cheaper
if it's gas-fired, but it's still the same amount of energy, so it's
unlikely to have a huge impact on climate change.

This is an old (and thoroughly discredited) logical error. Saving 45
watts of energy is not the same as saving 45 watts of heat. For a
start, most of that energy is expended in doing the 'work' - e.g.
lighting lights, spinning discs, and so on. Any excess heat generated
after that (unnecessary) work is done is minimal.

By your logic, if I leave a Sky+ box on standby, then the 20 watts it
spends on spinning the hard disc is converted into 20 watts of heat.
If that were true, it would turn Sky+ into a free energy machine -
which is impossible - breaking every scientific law there is.

Your 45 watts of wasted energy probably results in (I'm guessing here)
maybe 2 watts of heat. Whatever heating system you have is going to be
a FAR more efficient way of generating an equivalent amount of heat.
And considerably cheaper too.

Saving 45 watts at current electricity prices cuts about £40 a year
off your electricity bills. It's just burning money. (And, before you
even suggest it, burning five pound notes is not an efficient way of
heating your home either.)
--

On Tue, 15 Sep 2009 09:39:13 +0100, Norman Wells wrote:
Vortex4 wrote:
"alexander.keys1" wrote in message
...
There have been a lot of comments recently about the waste of energy
due to appliances being left on standby, and various gizmo's that are
on offer to turn them off automatically, or otherwise purporting to
save energy. What everybody seems to be forgetting is that an energy-
saving device comes with most UK socket outlets, it's called a
'switch', and when put into the 'off' position, power cosumption is
zero! None of my appliances, including computers, digital TV
receivers, etc. have come to harm through this practice, I always
switch off at the wall, back in the day when there were fewer
appliances this was standard procedure to avoid fire risk.

David Mackays book is a good read on this subject:
http://www.inference.phy.cam.ac.uk/w...page_155.shtml

So he says he can save all of 45 watts if he turns everything off instead of
leaving it on standby when he's not using it. The equivalent of a very dim
lightbulb therefore. Great!

Which in the very next sentence he states is a saving of £45 per year. Sounds
worth having, esp. as it's savings from taxed income.

However, he ignores the fact that he's also losing 45 watts of heat. To
keep his house at exactly the same temperature, an extra 45 watts of heat
need to be pumped out by whatever heating system he has, for as much of the
year as he needs any heating at all. Admittedly, that may be a bit cheaper
if it's gas-fired, but it's still the same amount of energy, so it's
unlikely to have a huge impact on climate change.

True, as far as it goes. However for (depending where you live & how well
insulated your house is) half the year, it's wasted heat. Plus it doesn't
contribute to the _usable_ room environment when the occupants are asleep
or out - which for a single person, or couple both working is a significant
proportion of the week.
And, the £45 you save buys you more gas heating than this wasted leccy
provides, so the saving is definitely worthwhile on a purely financial
basis, as _well_ as a social / moral position of profligate energy use.

On Sep 15, 12:02*pm, (Zero Tolerance)
wrote:
On Tue, 15 Sep 2009 09:39:13 +0100, "Norman Wells"

wrote:
However, he ignores the fact that he's also losing 45 watts of heat. *To
keep his house at exactly the same temperature, an extra 45 watts of heat
need to be pumped out by whatever heating system he has, for as much of the
year as he needs any heating at all. *Admittedly, that may be a bit cheaper
if it's gas-fired, but it's still the same amount of energy, so it's
unlikely to have a huge impact on climate change.

This is an old (and thoroughly discredited) logical error. Saving 45
watts of energy is not the same as saving 45 watts of heat. For a
start, most of that energy is expended in doing the 'work' - e.g.
lighting lights, spinning discs, and so on. Any excess heat generated
after that (unnecessary) work is done is minimal.

By your logic, if I leave a Sky+ box on standby, then the 20 watts it
spends on spinning the hard disc is converted into 20 watts of heat.

It is.

If that were true, it would turn Sky+ into a free energy machine -

It's taken 20W from the mains supply. How is that "free"?

which is impossible - breaking every scientific law there is.

I think a few laws were broken when they let you loose on society.

Your 45 watts of wasted energy probably results in (I'm guessing here)
maybe 2 watts of heat.

What do you think happens to the other 43W?

MBQ