In article ,
(Doug Miller) wrote:

In article , Smitty Two
wrote:
In article ,
(Doug Miller) wrote:

In article , Smitty
Two
wrote:

A house is not a water heater. The overwhelming majority of the energy
used to maintain a water heater comes from *using* the hot water and
heating the replacement cold water. You aren't using the air in your
home, it's leaking out.

How is warm air leaking out of a house -- and consequently being replaced
by
colder air leaking in -- meaningfully different from warm water being
withdrawn from a water heater and being replaced by colder water?

The only one who coughed up anecdotal numbers from the real world in
this thread said his electric bill went down by $40 when he switched
from electricity to NG to heat his water.

Plausible IMHO.

Let's say 90% of that money went to heating cold water coming in, which
replaced the warm water going out. And 10% of that money went to making
up for "unintentional" heat loss.

Also plausible.

That's $4, total cost of unwanted heat loss. And let's say that turning
off the WH at night saves, oh, maybe 5% of the energy that leaving it on
all night uses. The OP defined all night as 10 hours.
(10/24)(0.05)($4.00) = $0.08.

I wonder at your guesstimate of 5% ...

I stand corrected. I said the OP couldn't save a plug nickel. My new
position is, he could save *eight cents per month.*

.. just off the cuff, I'd regard 20% as a more plausible figure -- which
brings the savings all the way up to a penny a day. Those pennies add up, you
know. ;-)

On second thought, I bet the timer costs .08 to run every month. I'm
going back to my plug nickel assertion.

Depends on which guesstimate is closer to correct: your 5%, or my 20%. I just
had a look at the Dayton Electric Timer which was left here by the previous
owner; it has a 3-watt motor. 3w * 24 hrs/day * 30 days/mo = 2160 watt-hrs/mo
= just over 2 kwh per month. Assume ten cents / kwh; at 5%, you're wasting
money, but at 20% you're saving. Not much, admittedly, but still non-zero.

I'll let you work out how long it takes to recoup the cost of the timer. :-)

You seem like a smart guy, Doug. I think you can figure out what I mean
when I say turning off a WH isn't the same as turning down the house
heat at night.

If by that you mean -- yes, the two situations operate on the same principle
exactly, but the amount of money saved on the water heater is so small as to
be not worth consideration -- then we agree. If you mean something other than
that, then we probably disagree.

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

In article , Smitty Two wrote:

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

I disagree. By shutting off the water heater at night you are also lowering
the average temperature of the water -- and the situations are the same.

In article ,
(Doug Miller) wrote:

In article , Smitty Two
wrote:

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

I disagree. By shutting off the water heater at night you are also lowering
the average temperature of the water -- and the situations are the same.

Sure. But you "use" the air in the house a little differently than you
"use" the water in the tqnk. You aren't lowering the average temperature
of the water that you use, at all. That's the difference.

On Aug 8, 11:42*pm, Smitty Two wrote:
In article ,
(Doug Miller) wrote:

In article , Smitty Two
wrote:

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

I disagree. By shutting off the water heater at night you are also lowering
the average temperature of the water -- and the situations are the same..

Sure. But you "use" the air in the house a little differently than you
"use" the water in the tqnk. You aren't lowering the average temperature
of the water that you use, at all. That's the difference.

Talking about "using" the air in the house is a complete distraction
and has nothing to do with the heat loss principle at work here. I
could have two water heaters, one uninsulated, the other insulated.
Both of them are filled with water and have the water inlet valves
turned off. Hence there is zero water "used" in either case. Are
you going to tell us that one tank doesn't consume more energy than
the other? Or how about we set one tank to 110 and the other to
140? The 140 tank is going to use more energy than the 110, even with
zero water "use".

And also, while it doesn't matter, you are lowering the average
temperature of some of the water you use with a timer. Typically
you'd set the timer to turn the water heater off some time before you
go to bed, because the tank will still be full of hot water for any
use in the last hour or two and the longer it's turned off, the
greater the savings. After the timer turns it off, if you then draw
enough water, which likely would occur occasionally, you are in fact
using water at less than normal temp. Or if someone happens to wake
up at 3AM and draws hot water, it's at a lower than normal temp.

But the bottom line is, this discussion about air being "used" has
nothing to do with the physics of the water heater or the house
situation. The energy savings are a function of the fact that heat
loss is proportional to the temp difference between whatever is hot
and being heated and the temp of the surroundings. The lower the
temp difference, the lower the rate of heat loss.

On Aug 8, 7:34*pm, Smitty Two wrote:
In article
,





wrote:
On Aug 8, 12:46*pm, Smitty Two wrote:
In article
,

wrote:
On Aug 7, 9:47*am, ransley Mark wrote:
On Aug 6, 8:31*pm, "Jordan" wrote:

I just started thinking about getting an electric water heater timer
for
my
3 year old 30 gallon water heater. *I checked some of the reviews for
the
Intermatic timers and it looks like everybody loves them and they say
they
practically get their $40 bucks back each month.

Are timers all they seem to be cracked up to be and will turning off
the
water heater from 10 PM to 8 AM really save a family of 4 a big chunk
of
change each month?

Nobody is getting 40 back, My total bill for the electric tank was
under 40 a month, I know because that is how much it went down when I
switched to Ng. Do a test, my tank still had warm water in it after 5
days when I would leave and turn off the power. See how much it drops
overnight, you will be just reheating it and may save nothing.

Of course it has to be reheated, but once again, that DOES NOT
TRANSLATE INTO SAVING NOTHING. * In fact, the more it has to be
reheated, the MORE he saves.

Sorry, not true.

Exactly what is not true? * This is what you stated:

"See how much it drops overnight, you will be just reheating it and
may save nothing.

I didn't say that. We're getting into quote confusion, now.





'

That is what is not true and doesn't make any sense. *Of course it has
to be reheated the next morning. * The point, once again, is that it
takes less energy to then reheat it in the morning than it does to
maintain it at the normal set temp all night. * This is exactly the
same concept and simple physics as turning back a thermostat overnight
on a home heating system. * Are you going to tell us that doesn't save
energy too?

And again, let me state the disclaimer, I'm not saying he's going to
save a lot of energy. *I'm not saying it's worth it to install a
timer. * Maybe it is, maybe it isn't depending on exactly how much
energy he can save. * But that is a totally different argument than
saying turning off the water heater doesn't save any energy because it
has to be reheated.

It's the change in *rate* of heat loss that determines
the savings. The rate slows, slightly, as the temperature difference
between the water in the tank and the surrounding air decreases. But
that difference is essentially negligible.

IOW, looking at a loss of 20 degrees in 10 hours overnight: if it loses
10 degrees in the first five hours and another 10 in the second five
hours, there is absolutely *zero* savings.

Let's look at the previous example you gave he

Let's say your HW is at 130 degrees, and it cools to 110 overnight in
the tank with the heater off. Do you *really* think that the slope of
temp over time isn't close enough to linear to disregard its
shallowing
in this *real world* consideration?

The rate of heat loss is proportional to the temp difference. * Let's
assume it's in a basement at 60 degrees. *At 130 degrees, the temp
differential is 130-60, or 70 degrees. * At 110, it's 110-60 or 50
degrees. * So the temperature differential has gone from 70 to 50, or
about a 30% difference at the end of the period. * * It's a decaying
exponential so more of that 30% benefit occurs in the earlier period
than in the later. * But even if you assumed it was linear and went
from 0 decrease to 30% at the end of the period, *the tank would have
an average of about 15% less heat loss over say 6 hours. * That isn't
zero and it's not negligible either. *Again, whether it makes it
worthwhile to install a timer is a completely different discussion.

*However, if it loses 10.1
degrees in the first five hours and 9.9 degrees in the second five
hours, then you'll save by turning it off overnight. How much? Maybe a
penny. Likely not even that.

Clearly that can't happen. because the rate of heat loss is
proportional to the temp difference and it's a natural log decaying
function, which according to physics and math isn't close to being
linear. *In other words, it's going to lose much less in the second
five hours.

I'm pretty sure that if you look at a short enough section of a
logarithmic curve, it approaches a straight line. I think the WH cooling
graph overnight fits that approximation. Yes, it's an approximation. I
was the first one to acknowledge that I am approximating. So what?

In your own water heater example that you gave, with a timer, the
temperature delta goes from 70 to 50. That's a very significant move
on a decaying exponential curve and isn't approaching a straight
line. If what you're saying were true, what about a house setting
back the temp overnight? Let's say it's 22 deg outside, 72 inside
during the day. That's a delta of 50. At night we set it back to
62. The delta is now 40. So, it's widely accepted that a delta of
going from 50 to 40 saves a reasonable amount of energy, but a delta
going from 70 to 50 is so insignificant that it matters not a whit?
What kind of physics is that?




Show me some data that says a well-insulated tank in a heated area of a
house loses so much heat overnight that a person could save any
significant amount of money. Otherwise, let's just agree to disagree on
this one.- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -


As I recall, the point of contention here was NOT whether a timer
saves a significant amount of money. It was about statements you made
that defy physics:

"I don't think it'll save you a plug nickel. The amount of heat lost
during those 10 hours is exactly the amount of heat that has to be
put
back in. It doesn't matter one whit whether it's done all at once in
the
morning, or incrementally throughout the night. "

From simple physics, that statement is false. Had you said, I don't
think the energy saved is enough to make it worthwhile, we wouldn't be
having this disagreement.

"For all intents and purposes*, you don't save until it's been off
long enough to
cool down to whatever temp your cold water supply is. "

Which is also false. From physics, there is nothing special about it
cooling down to the cold water temp, any more than a house needs to
cool down to the 20 degree outside temp in winter to save money by
setting back the thermostat at night.


"Every speck of heat lost through the night
has to be replaced. Do it in small chunks, or do it all at once. Same
amount of energy is expended, disregarding the *very* minor
difference
noted (that rate of heat loss decreases as temp. differential
decreases.) "

Same could be said for the house setback example, which then lead to
the distraction of air in a house somehow being used? The fact that
the rate of heat loss decreases IS the whole point. I've said right
from the start that whether the savings would actually make it
worthwhile to do is another question. But you seem to seek to
obfuscate and dismiss the physics, rather than focus on what is
occuring and then figure out if it's worthwhile.


"It will use just as much electricity if it comes on for one hour
every
day, making up the whole 50 degrees at once, or if it comes on for
six
minutes, 10 times per day, increasing the water temp in the tank 5
degrees each time. "

Another false statement. If you had said it will use only a small
amount less if heated only once a day, then it would be true. But
as it stands, it's obviously false.

"It doesn't matter one whit whether it's done all at once in the
morning, or incrementally throughout the night. "

Again false and defies basic physics.

Now as for whether you can actually save money and how much, I
already showed you the DOE website, where it says you can save money
by installing a timer to either:

A - Lower the temp at night

B- Have the water heater run during periods when electricity is lower,
if that is available

But you just dismissed it. Here it is again:

http://www.eere.energy.gov/consumer/.../mytopic=13110
If you have an electric water heater, you can save an additional 5%–
12% of energy by installing a timer that turns it off at night when
you don't use hot water and/or during your utility's peak demand
times.

I would interpret that to mean that the low end, 5% savings is
achieved by using a timer with flat rate electric. And the 12% high
end is achieved by using a timer to get off-peak lower rates.
Whatever the numbers, clearly DOE, by the use of the words and/or,
endorses using timers even when you don't have a rate differential.
So, I would say that means they don't agree with you that it doesn't
matter a whit.


Here, from Popular Mechanics:

http://www.popularmechanics.com/home...html?series=25
2. Night Wise
Put a timer on your electric water heater that turns it off while
you’re asleep or keeps it off during peak hours—especially if you sign
up for time-of-use pricing.


From the state of California:

http://www.fypower.org/res/tools/ene...=water-heating
For electric water heaters, install a timer that can automatically
turn the heater off at night and on in the morning. A simple timer can
pay for itself in energy saved in about one year. More expensive,
multisetting timers are also available.


Do I think this means it's worth the trouble, expense, etc to actually
do? Not necessarily. But I do think it justifies the physics of
what is going on and shows that these sources do think the energy
savings are non zero and matter more than a whit.

In article
,
wrote:

On Aug 8, 11:42*pm, Smitty Two wrote:
In article ,
(Doug Miller) wrote:

In article , Smitty
Two
wrote:

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

I disagree. By shutting off the water heater at night you are also
lowering
the average temperature of the water -- and the situations are the same.

Sure. But you "use" the air in the house a little differently than you
"use" the water in the tqnk. You aren't lowering the average temperature
of the water that you use, at all. That's the difference.

Talking about "using" the air in the house is a complete distraction
and has nothing to do with the heat loss principle at work here.

But it *is* relevant. The fact that you don't see the relevance makes me
think there's a significant piece of the puzzle to which you've turned a
stubbornly blind eye.

I
could have two water heaters, one uninsulated, the other insulated.
Both of them are filled with water and have the water inlet valves
turned off. Hence there is zero water "used" in either case. Are
you going to tell us that one tank doesn't consume more energy than
the other? Or how about we set one tank to 110 and the other to
140? The 140 tank is going to use more energy than the 110, even with
zero water "use".

I agree that the uninsulated tank uses more energy. I agree that the
tank with the higher setting uses more energy. In fact, the way to save
on your HW costs is to lower the setting. That is the equivalent to
lowering your thermostat at your house.


And also, while it doesn't matter, you are lowering the average
temperature of some of the water you use with a timer. Typically
you'd set the timer to turn the water heater off some time before you
go to bed, because the tank will still be full of hot water for any
use in the last hour or two and the longer it's turned off, the
greater the savings. After the timer turns it off, if you then draw
enough water, which likely would occur occasionally, you are in fact
using water at less than normal temp. Or if someone happens to wake
up at 3AM and draws hot water, it's at a lower than normal temp.

*Exactly.* I agree 100%. And that's the *only* significant reason why
turning off the heater at night might help, because it forces you to use
less hot water, and forces you to use hot water that is at a lower temp,
assuming your scenarios take place, which they likely do. Wouldn't it
make more sense to just lower the setting 24/7, if saving money is the
objective?


But the bottom line is, this discussion about air being "used" has
nothing to do with the physics of the water heater or the house
situation. The energy savings are a function of the fact that heat
loss is proportional to the temp difference between whatever is hot
and being heated and the temp of the surroundings. The lower the
temp difference, the lower the rate of heat loss.

And as I said in response to Doug, it's likely that turning off the WH
heater at night to reduce the rate of heat loss might save enough to
power the timer. He thinks so, by a few pennies. I don't.

In article
,
wrote:

On Aug 8, 7:34*pm, Smitty Two wrote:
In article
,





wrote:
On Aug 8, 12:46*pm, Smitty Two wrote:
In article
,

wrote:
On Aug 7, 9:47*am, ransley Mark wrote:
On Aug 6, 8:31*pm, "Jordan" wrote:

I just started thinking about getting an electric water heater
timer
for
my
3 year old 30 gallon water heater. *I checked some of the reviews
for
the
Intermatic timers and it looks like everybody loves them and they
say
they
practically get their $40 bucks back each month.

Are timers all they seem to be cracked up to be and will turning
off
the
water heater from 10 PM to 8 AM really save a family of 4 a big
chunk
of
change each month?

Nobody is getting 40 back, My total bill for the electric tank was
under 40 a month, I know because that is how much it went down when
I
switched to Ng. Do a test, my tank still had warm water in it after
5
days when I would leave and turn off the power. See how much it
drops
overnight, you will be just reheating it and may save nothing.

Of course it has to be reheated, but once again, that DOES NOT
TRANSLATE INTO SAVING NOTHING. * In fact, the more it has to be
reheated, the MORE he saves.

Sorry, not true.

Exactly what is not true? * This is what you stated:

"See how much it drops overnight, you will be just reheating it and
may save nothing.

I didn't say that. We're getting into quote confusion, now.





'

That is what is not true and doesn't make any sense. *Of course it has
to be reheated the next morning. * The point, once again, is that it
takes less energy to then reheat it in the morning than it does to
maintain it at the normal set temp all night. * This is exactly the
same concept and simple physics as turning back a thermostat overnight
on a home heating system. * Are you going to tell us that doesn't save
energy too?

And again, let me state the disclaimer, I'm not saying he's going to
save a lot of energy. *I'm not saying it's worth it to install a
timer. * Maybe it is, maybe it isn't depending on exactly how much
energy he can save. * But that is a totally different argument than
saying turning off the water heater doesn't save any energy because it
has to be reheated.

It's the change in *rate* of heat loss that determines
the savings. The rate slows, slightly, as the temperature difference
between the water in the tank and the surrounding air decreases. But
that difference is essentially negligible.

IOW, looking at a loss of 20 degrees in 10 hours overnight: if it loses
10 degrees in the first five hours and another 10 in the second five
hours, there is absolutely *zero* savings.

Let's look at the previous example you gave he

Let's say your HW is at 130 degrees, and it cools to 110 overnight in
the tank with the heater off. Do you *really* think that the slope of
temp over time isn't close enough to linear to disregard its
shallowing
in this *real world* consideration?

The rate of heat loss is proportional to the temp difference. * Let's
assume it's in a basement at 60 degrees. *At 130 degrees, the temp
differential is 130-60, or 70 degrees. * At 110, it's 110-60 or 50
degrees. * So the temperature differential has gone from 70 to 50, or
about a 30% difference at the end of the period. * * It's a decaying
exponential so more of that 30% benefit occurs in the earlier period
than in the later. * But even if you assumed it was linear and went
from 0 decrease to 30% at the end of the period, *the tank would have
an average of about 15% less heat loss over say 6 hours. * That isn't
zero and it's not negligible either. *Again, whether it makes it
worthwhile to install a timer is a completely different discussion.

*However, if it loses 10.1
degrees in the first five hours and 9.9 degrees in the second five
hours, then you'll save by turning it off overnight. How much? Maybe a
penny. Likely not even that.

Clearly that can't happen. because the rate of heat loss is
proportional to the temp difference and it's a natural log decaying
function, which according to physics and math isn't close to being
linear. *In other words, it's going to lose much less in the second
five hours.

I'm pretty sure that if you look at a short enough section of a
logarithmic curve, it approaches a straight line. I think the WH cooling
graph overnight fits that approximation. Yes, it's an approximation. I
was the first one to acknowledge that I am approximating. So what?

In your own water heater example that you gave, with a timer, the
temperature delta goes from 70 to 50. That's a very significant move
on a decaying exponential curve and isn't approaching a straight
line. If what you're saying were true, what about a house setting
back the temp overnight? Let's say it's 22 deg outside, 72 inside
during the day. That's a delta of 50. At night we set it back to
62. The delta is now 40. So, it's widely accepted that a delta of
going from 50 to 40 saves a reasonable amount of energy, but a delta
going from 70 to 50 is so insignificant that it matters not a whit?
What kind of physics is that?

What kind? It's real world physics. IOW, logic is applied to it.
The average air temperature in the home changes when you set back the
thermostat at night. The average temperature of the water heater in the
tank that you *use* (disregarding taking a cold shower in the morning if
you got up earlier than the tank recovered) *doesn't change.*

You have to factor in that 100% of the heat loss from the house is
unintentional, while maybe 10% (at the most, it's probably more like 5%
or 3%) of the heat loss from the WH is unintentional.





Show me some data that says a well-insulated tank in a heated area of a
house loses so much heat overnight that a person could save any
significant amount of money. Otherwise, let's just agree to disagree on
this one.- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -


As I recall, the point of contention here was NOT whether a timer
saves a significant amount of money. It was about statements you made
that defy physics:

I never made any statements that defy physics. I stated right off the
bat that I was *intentionally ignoring* the decaying heat loss curve
because it wasn't significant to the question of whether the OP could
save money. As I estimated yesterday, he could save about eight cents,
not enough to power the timer.


"I don't think it'll save you a plug nickel. The amount of heat lost
during those 10 hours is exactly the amount of heat that has to be
put
back in. It doesn't matter one whit whether it's done all at once in
the
morning, or incrementally throughout the night. "

From simple physics, that statement is false. Had you said, I don't
think the energy saved is enough to make it worthwhile, we wouldn't be
having this disagreement.

We seem to be having it, though. And the phrase *I don't think you'll
save a plug nickel* translates to *I don't think the energy saved is
enough to make it worthwhile.*


"For all intents and purposes*, you don't save until it's been off
long enough to
cool down to whatever temp your cold water supply is. "

Which is also false. From physics, there is nothing special about it
cooling down to the cold water temp, any more than a house needs to
cool down to the 20 degree outside temp in winter to save money by
setting back the thermostat at night.

Like hell there isn't anything significant about it. Heat loss stops
altogether at equilibrium. That's the jacuzzi heating logic. Use it
daily, keep it hot. Use it monthly, let it cool.



"Every speck of heat lost through the night
has to be replaced. Do it in small chunks, or do it all at once. Same
amount of energy is expended, disregarding the *very* minor
difference
noted (that rate of heat loss decreases as temp. differential
decreases.) "

Same could be said for the house setback example, which then lead to
the distraction of air in a house somehow being used? The fact that
the rate of heat loss decreases IS the whole point. I've said right
from the start that whether the savings would actually make it
worthwhile to do is another question. But you seem to seek to
obfuscate and dismiss the physics, rather than focus on what is
occuring and then figure out if it's worthwhile.


"It will use just as much electricity if it comes on for one hour
every
day, making up the whole 50 degrees at once, or if it comes on for
six
minutes, 10 times per day, increasing the water temp in the tank 5
degrees each time. "

Another false statement. If you had said it will use only a small
amount less if heated only once a day, then it would be true. But
as it stands, it's obviously false.

"It doesn't matter one whit whether it's done all at once in the
morning, or incrementally throughout the night. "

Again false and defies basic physics.

Huh? You must mean your decaying heat loss curve, again. The one that's
insignificant as far as saving any money. Or is there another issue you
have with that?


Now as for whether you can actually save money and how much, I
already showed you the DOE website, where it says you can save money
by installing a timer to either:

A - Lower the temp at night

B- Have the water heater run during periods when electricity is lower,
if that is available

But you just dismissed it.

I dismissed A. It's nonsense. B, I agree with 100%

Here it is again:

http://www.eere.energy.gov/consumer/your home/water
heating/index.cfm/mytopic=13110
If you have an electric water heater, you can save an additional 5%*
12% of energy by installing a timer that turns it off at night when
you don't use hot water and/or during your utility's peak demand
times.

I would interpret that to mean that the low end, 5% savings is
achieved by using a timer with flat rate electric.

Nuts. Standby losses are so low in a modern water heater that even
though I speculated that 10% of the total energy used goes to counter
them, I'd say it's 5%. So the DOE thinks a timer will eliminate standby
losses altogether? Since you seem to like to pick on my understanding of
physics, I'll suggest yours needs a tune-up if you believe that.

And the 12% high
end is achieved by using a timer to get off-peak lower rates.
Whatever the numbers, clearly DOE, by the use of the words and/or,
endorses using timers even when you don't have a rate differential.
So, I would say that means they don't agree with you that it doesn't
matter a whit.



Here, from Popular Mechanics:

http://www.popularmechanics.com/home journal/how to/4217039.html?series=25
2. Night Wise
Put a timer on your electric water heater that turns it off while
you¹re asleep or keeps it off during peak hours‹especially if you sign
up for time-of-use pricing.


From the state of California:

http://www.fypower.org/res/tools/energy tips results.html?tips=water-heating
For electric water heaters, install a timer that can automatically
turn the heater off at night and on in the morning. A simple timer can
pay for itself in energy saved in about one year. More expensive,
multisetting timers are also available.


Do I think this means it's worth the trouble, expense, etc to actually
do? Not necessarily. But I do think it justifies the physics of
what is going on and shows that these sources do think the energy
savings are non zero and matter more than a whit.

In article , Smitty Two wrote:

And as I said in response to Doug, it's likely that turning off the WH
heater at night to reduce the rate of heat loss might save enough to
power the timer. He thinks so, by a few pennies. I don't.

We certainly agree on one thing, anyway: the amount of money saved is not
likely to amount to much, even when measured over a span of many years.

On Aug 9, 9:48*am, Smitty Two wrote:

In your own water heater example that you gave, with a timer, the
temperature delta goes from 70 to 50. *That's a very significant move
on a decaying exponential curve and isn't approaching a straight
line. * If what you're saying were true, what about a house setting
back the temp overnight? * Let's say it's 22 deg outside, 72 inside
during the day. * That's a delta of 50. *At night we set it back to
62. *The delta is now 40. * So, it's widely accepted that a delta of
going from 50 to 40 saves a reasonable amount of energy, but a delta
going from 70 to 50 is so insignificant that it matters not a whit?
What kind of physics is that?

What kind? It's real world physics. IOW, logic is applied to it.
The average air temperature in the home changes when you set back the
thermostat at night. The average temperature of the water heater in the
tank that you *use* (disregarding taking a cold shower in the morning if
you got up earlier than the tank recovered) *doesn't change.*


And there you go again, with another silly statement that defies
physics. You yourself gave an example where you stated:

"Let's say your HW is at 130 degrees, and it cools to 110 overnight in
the tank with the heater off. Do you *really* think that the slope of
temp over time isn't close enough to linear to disregard its
shallowing
in this *real world* consideration?"


And now you say the temperature doesn't change at all? Or that it
matters if the water is used or not? You are totally confused. By
keeping the water heater from coming on during the night and reheating
itself, energy is saved. Period.




You have to factor in that 100% of the heat loss from the house is
unintentional, while maybe 10% (at the most, it's probably more like 5%
or 3%) of the heat loss from the WH is unintentional.



The heat loss from both the house cooling slighltly over night and the
water heater cooling slightly over night are both unintentional. Not
that it makes any difference, as if the physics depend on what is
intentional or not. It's this simple: The rate of heat loss is
proportional to the temp difference and applies in both cases.










Show me some data that says a well-insulated tank in a heated area of a
house loses so much heat overnight that a person could save any
significant amount of money. Otherwise, let's just agree to disagree on
this one.- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

As I recall, the point of contention here was NOT whether a timer
saves a significant amount of money. *It was about statements you made
that defy physics:

I never made any statements that defy physics. I stated right off the
bat that I was *intentionally ignoring* the decaying heat loss curve
because it wasn't significant to the question of whether the OP could
save money.

Well, duh! That's like saying you won't save any heat in a house by
setting back the temp at night and then following it up with the
disclaimer that you're intentionally ignoring the heat loss curve
because it's not significant to the question. In fact, it's the
entire point.


As I estimated yesterday, he could save about eight cents,
not enough to power the timer.


Number pulled wildly from the air, while you completely ignore the DOE
that had an estimate of 5% at the low end. You think mabye the DOE
knows and has tested things more than you?





"I don't think it'll save you a plug nickel. The amount of heat lost
during those 10 hours is exactly the amount of heat that has to be
put
back in. It doesn't matter one whit whether it's done all at once in
the
morning, or incrementally throughout the night. "

From simple physics, that statement is false. * Had you said, I don't
think the energy saved is enough to make it worthwhile, we wouldn't be
having this disagreement.

We seem to be having it, though. And the phrase *I don't think you'll
save a plug nickel* translates to *I don't think the energy saved is
enough to make it worthwhile.*



"For all intents and purposes*, you don't save until it's been off
long enough to
cool down to whatever temp your cold water supply is. "

Which is also false. * From physics, there is nothing special about it
cooling down to the cold water temp, any more than a house needs to
cool down to the 20 degree outside temp in winter to save money by
setting back the thermostat at night.

Like hell there isn't anything significant about it. Heat loss stops
altogether at equilibrium. That's the jacuzzi heating logic. Use it
daily, keep it hot. Use it monthly, let it cool.



Sure it stops at equilibrium. So what? That doesn't mean you aren't
saving energy at a lower than normal temp. Or that you aren't saving
as the temp drops to it's final temp. Gheez, if that were true, with
it 20 deg outside, the only way you'd save any energy would be to have
the jacuzzi drop to 20 deg and freeze solid. Or that to save energy
with a setback thermostat in a house, you'd have to let it go down to
20 deg inside. Yet, we know that in both those cases, going to a
lower temp does save energy. Exact same thing with the water heater.







"Every speck of heat lost through the night
has to be replaced. Do it in small chunks, or do it all at once. Same
amount of energy is expended, disregarding the *very* minor
difference
noted (that rate of heat loss decreases as temp. differential
decreases.) "

Same could be said for the house setback example, which then lead to
the distraction of air in a house somehow being used? * The fact that
the rate of heat loss decreases IS the whole point. * I've said right
from the start that whether the savings would actually make it
worthwhile to do is another question. * But you seem to seek to
obfuscate and dismiss the physics, rather than focus on what is
occuring and then figure out if it's worthwhile.

"It will use just as much electricity if it comes on for one hour
every
day, making up the whole 50 degrees at once, or if it comes on for
six
minutes, 10 times per day, increasing the water temp in the tank 5
degrees each time. "

Another false statement. * If you had said it will use only a small

...



Now, I'm actually starting to get annoyed. You asked for references
that said using a timer on a water heater works to save energy. I
gave you 3. The DOE, the state of California and Popular Mechanics,
which seem reasonable and credible. All 3 state that installing a
timer on a water heater does save energy and recommend doing it.
And your response? You just ignore it.

Where are your references that back up any of the silly nonsense
you've stated? I'd especially like to see one that talks about air
being "used" as essential to saving heat in a home by setting back the
thermostat at night. Or one that says you only save energy when the
heated object coolst to it's final temp. Or one that talks about the
heat loss having to be intentional vs unintentional. Do a google on
any of these topics and show us where we can find it.

In article
,
wrote:

By
keeping the water heater from coming on during the night and reheating
itself, energy is saved. Period.

We're debating too many issues at once, here, and I'm growing annoyed,
too. You think I'm crazy, I think you are. So I'm going to address this
one issue and ask you one question, and then I'm done with this thread.

I want you to set aside the agreed upon fact that water cools more
slowly as the delta t drops. (We clearly disagree on how significant
that is, in the real world water heater example. Fine, just please set
it aside for the sake of this one question.)

And I want you to set aside any notion that someone may get up in the
night and wash his hands, or that someone get up and take a shower
before the tank has fully recovered.

Now given those constraints, suppose the water in the tank drops by 15
degrees overnight. Do you think it takes less energy to heat the water
in the morning by the whole fifteen degrees, than it would take to
reheat the water three times during the night, each time it drops 5
degrees?

This is a YES or NO question!

On Aug 9, 10:39*am, Smitty Two wrote:
In article
,

wrote:
By
keeping the water heater from coming on during the night and reheating
itself, energy is saved. * Period.

We're debating too many issues at once, here, and I'm growing annoyed,
too. You think I'm crazy, I think you are. So I'm going to address this
one issue and ask you one question, and then I'm done with this thread.

I want you to set aside the agreed upon fact that water cools more
slowly as the delta t drops. (We clearly disagree on how significant
that is, in the real world water heater example. Fine, just please set
it aside for the sake of this one question.)

And I want you to set aside any notion that someone may get up in the
night and wash his hands, or that someone get up and take a shower
before the tank has fully recovered.

Now given those constraints, suppose the water in the tank drops by 15
degrees overnight. Do you think it takes less energy to heat the water
in the morning by the whole fifteen degrees, than it would take to
reheat the water three times during the night, each time it drops 5
degrees?

This is a YES or NO question!


That's a simple and straightforward questioned answered by physics.
And the answer is yes. Because by reheating it every time it drops 5
degrees, the water is maintained at a higher temp all night resulting
in more heat loss from the tank to the surroundings.

On Aug 9, 11:10�am, wrote:
On Aug 9, 10:39�am, Smitty Two wrote:





In article
,

wrote:
By
keeping the water heater from coming on during the night and reheating
itself, energy is saved. � Period.

We're debating too many issues at once, here, and I'm growing annoyed,
too. You think I'm crazy, I think you are. So I'm going to address this
one issue and ask you one question, and then I'm done with this thread.

I want you to set aside the agreed upon fact that water cools more
slowly as the delta t drops. (We clearly disagree on how significant
that is, in the real world water heater example. Fine, just please set
it aside for the sake of this one question.)

And I want you to set aside any notion that someone may get up in the
night and wash his hands, or that someone get up and take a shower
before the tank has fully recovered.

Now given those constraints, suppose the water in the tank drops by 15
degrees overnight. Do you think it takes less energy to heat the water
in the morning by the whole fifteen degrees, than it would take to
reheat the water three times during the night, each time it drops 5
degrees?

This is a YES or NO question!

That's a simple and straightforward questioned answered by physics.
And the answer is yes. � Because by reheating it every time it drops 5
degrees, the water is maintained at a higher temp all night resulting
in more heat loss from the tank to the surroundings.- Hide quoted text -

- Show quoted text -

my old gas heater devloped a leak at the top, so I turned it off till
morning.

turned it on for a quick shower in the morning.

water still nice and hot.

before buying timer first step should be checking how much water cools
over nite.

then go from there.

I had the same issue last fall. My wife has been home raising the kids for
the past 5 years, but now they started school and my wife just got a job at
the school. So now no one is home from 7-4 leaving every light and TV in
the house on like they have been for the past 5 years. Also I replace every
single bulb in the house with the CF bulbs. I was expecting a nice 20% or
more drop in KWH on my Sept bills on. - WRONG

My electric bill went UP 15% more KWH than the previous year. I called
National Grid to complain that the meter had to be screwed up or something
because I know they do not estimate in my area. They have meters with those
electronic devices so the people reading don't even have to leave the car to
get a reading unless the radio is dead. Since I am never estimated and the
biggest energy wasters (the kids) are not home for 8+ hours a day now and
there had been no change in appliances or other factors there is no way it
could have gone up.

They said that they doubted it because everyone elses bills went up in usage
about that amount so mine should have. Then I hit them with "Did everyone
else's family start leaving their house vacant for over 45+ more hours a
week than mine?" Of course not so they started to make even more excuses as
far fetched as "sun spots" affecting my usage.

I really think that the do something very fishy there because I complained a
few times and they said they were not going to check unless there was a
drastic circumstance that they could know 100% that something was wrong. I
lied and I said that I was going away on vactaion for 3 week in March and
turning off the fridge, not using the dryer, the water pump, TV or even
leaving lights on so my bill should be squat.

Well guess what? I did not go away and they did not say they came out, but
right after I told them that something was coming up that was going to nail
them on a busted meter or a screw up, my bills since then went dow about the
expected 20%. Isn't that amazing. I am doing anything more than I was
before, but all of a sudden after the threats my bills magically drop the
20%.

"mm" wrote in message
...
On Thu, 07 Aug 2008 05:36:26 -0700, Smitty Two
wrote:

In article ,
mm wrote:

On Wed, 06 Aug 2008 20:09:53 -0700, Smitty Two
wrote:


There is one caveat. If your water heater is so poorly insulated or so
unfavorably situated that the water temp inside returns to supply
ambient before those ten hours elapse, then you'll save. Since you're
obviously energy conscious, that caveat likely doesn't apply.

I've turned off the electricity to my water heater and it stays pretty
hot for 3 days iirc. And it would stay hot a lot longer if I weren't
using the hot water. The major thing cooling off the water is the
cold water going in when I use hot water.


Usage is very strange. I went away for November and December (and my
billing periods were from the 15th to the 14th, and my bill was almost
the same as the previous year when I was here the whole time.

The water heater was off, and empty. The furnaace was down to about 45
and it's oil so it only used electricity to run the ignition and
blower, and the furance fan.

About 4 lights were on timers, but I leave 3 of them on timers even
when I'm home.

It was not an estimated reading.

I still haven't figured it out.

We love a good mystery. I'm sure you know that for comparison, it's
kilowatt-hours that count, not dollars. How old is that refrigerator?

Yeah, I forgot to say that I compared KwH, not dollars.

The fridge is only 29 years old, but when I was away, I didn't open
the door at all, so however high the electric usage it was, it should
have been less, a lot less, when I was away.

If I'm lucky I may go away for 2 months March and April of next
year**. I'll try to do a better job, if possible, of comparing then

**Prior to last years trip I hadn't been anywhere except to visit my
brother in 10 years. Plus I'm trying to sell a project on these trips
(but haven't attempted to deduct even a fraction of the costs. I don't
think I can since I've not gotten any revenue.)

Jordan wrote:

Are timers all they seem to be cracked up to be and will turning off the
water heater from 10 PM to 8 AM really save a family of 4 a big chunk of
change each month?

Only if electricity costs less at night.

Nick

Smitty Two wrote:

I don't think it'll save you a plug nickel. The amount of heat lost
during those 10 hours is exactly the amount of heat that has to be put
back in. It doesn't matter one whit whether it's done all at once in the
morning, or incrementally throughout the night.

Wrong, but if the heater has good insulation,the amount of heat saved
will be less than the energy used by the timer itself.

Nick

mm wrote:

I've turned off the electricity to my water heater and it stays pretty
hot for 3 days iirc. And it would stay hot a lot longer if I weren't
using the hot water. The major thing cooling off the water is the
cold water going in when I use hot water.

A very clever timer and a well-programmed family might save significant
energy if it turned on a half-hour before the first use of the day and
turned off before the last use, an hour later, leaving itself entirely
filled with cold water for 23 hours per day.

Nick

On Sat, 9 Aug 2008 17:12:57 -0400, "NJC" wrote:

I had the same issue last fall. My wife has been home raising the kids for
the past 5 years, but now they started school and my wife just got a job at
the school. So now no one is home from 7-4 leaving every light and TV in
the house on like they have been for the past 5 years. Also I replace every
single bulb in the house with the CF bulbs. I was expecting a nice 20% or
more drop in KWH on my Sept bills on. - WRONG

My electric bill went UP 15% more KWH than the previous year. I called
National Grid to complain that the meter had to be screwed up or something
because I know they do not estimate in my area. They have meters with those

They list on the My Bill part of the webpage if the bill is estimated,
and I too have the radio meter, so either they just have to drive by,
or they don't even have to leave the office.

The online bills here are just pdf files that are identical to the
printed bills that they mail, but I have the printed bills too. I
just have to find them all and put them in order.

electronic devices so the people reading don't even have to leave the car to
get a reading unless the radio is dead. Since I am never estimated and the
biggest energy wasters (the kids) are not home for 8+ hours a day now and
there had been no change in appliances or other factors there is no way it
could have gone up.

Yes, your story does sound a lot like my story. Even if the details
are different.

Since I don't know what National Grid is, you're probably not in
Baltimore (which is where I am), but the purpose of conventions is
partly to share trade secrets.

They said that they doubted it because everyone elses bills went up in usage

Why would anyone's usage in KwH go up, unless it was colder in the
winter or hotter in the summer than normal? I guess plasma tv's use
more electricity and bigger screens use more, but none of this affects
every home or could equal 15% for anyone.

about that amount so mine should have. Then I hit them with "Did everyone
else's family start leaving their house vacant for over 45+ more hours a
week than mine?" Of course not so they started to make even more excuses as
far fetched as "sun spots" affecting my usage.

I really think that the do something very fishy there because I complained a
few times and they said they were not going to check unless there was a
drastic circumstance that they could know 100% that something was wrong. I
lied and I said that I was going away on vactaion for 3 week in March and
turning off the fridge, not using the dryer, the water pump, TV or even
leaving lights on so my bill should be squat.

Good idea to tell them that.

And btw, if I do go away next year, I think I'll turn off the
refrigerator. I think I froze a half gallon of milk just before I
left, and drank it when I got home, but with a trifle extra planning,
there doesn't have to be any food left to spoil. If I go for Feb,
March, and April (a possibility**) and the furnace is set at 45, I
would think it wouldn't run at all the last month or two. Then there
should be almost nothing on.

I'm going to have to start verifying the meter readings also. Maybe
in general and before and after the trip. There are many far more
important reasons to go on this trip, (and to stay home) but somehow
the notion of checking up on them seems very important right now.

Well guess what? I did not go away and they did not say they came out, but
right after I told them that something was coming up that was going to nail
them on a busted meter or a screw up, my bills since then went dow about the
expected 20%. Isn't that amazing.

Quite amazing. Sounds hinky.

NOT, I"m sure you mean.
I am doing anything more than I was
before, but all of a sudden after the threats my bills magically drop the
20%.

I would have emailed you a copy, to make sure you saw this, but no big
deal.

**This time I'm going to try to rent a room in someone's apartment. I
don't know yet how much that would cost, maybe 300 or 400 a month?
Maybe young people. (If I were a little younger than I am, I could
date their friends.)

The last trip, for 9 weeks, cost me 5000 dollars for everything for
one person, including airfare, a 250 dollar camera and a 150 dollar
camera, and a professional 3-day/2-night tour to some historical city.
I know some people spend 5000 for a 2 weeks.

"mm" wrote in message
.. .
On Thu, 07 Aug 2008 05:36:26 -0700, Smitty Two
wrote:

In article ,
mm wrote:

On Wed, 06 Aug 2008 20:09:53 -0700, Smitty Two
wrote:


There is one caveat. If your water heater is so poorly insulated or so
unfavorably situated that the water temp inside returns to supply
ambient before those ten hours elapse, then you'll save. Since you're
obviously energy conscious, that caveat likely doesn't apply.

I've turned off the electricity to my water heater and it stays pretty
hot for 3 days iirc. And it would stay hot a lot longer if I weren't
using the hot water. The major thing cooling off the water is the
cold water going in when I use hot water.


Usage is very strange. I went away for November and December (and my
billing periods were from the 15th to the 14th, and my bill was almost
the same as the previous year when I was here the whole time.

The water heater was off, and empty. The furnaace was down to about 45
and it's oil so it only used electricity to run the ignition and
blower, and the furance fan.

About 4 lights were on timers, but I leave 3 of them on timers even
when I'm home.

It was not an estimated reading.

I still haven't figured it out.

We love a good mystery. I'm sure you know that for comparison, it's
kilowatt-hours that count, not dollars. How old is that refrigerator?

Yeah, I forgot to say that I compared KwH, not dollars.

The fridge is only 29 years old, but when I was away, I didn't open
the door at all, so however high the electric usage it was, it should
have been less, a lot less, when I was away.

If I'm lucky I may go away for 2 months March and April of next
year**. I'll try to do a better job, if possible, of comparing then

**Prior to last years trip I hadn't been anywhere except to visit my
brother in 10 years. Plus I'm trying to sell a project on these trips
(but haven't attempted to deduct even a fraction of the costs. I don't
think I can since I've not gotten any revenue.)

On Aug 9, 7:45�pm, mm wrote:
On Sat, 9 Aug 2008 17:12:57 -0400, "NJC" wrote:
I had the same issue last fall. �My wife has been home raising the kids for
the past 5 years, but now they started school and my wife just got a job at
the school. �So now no one is home from 7-4 leaving every light and TV in
the house on like they have been for the past 5 years. �Also I replace every
single bulb in the house with the CF bulbs. �I was expecting a nice 20% or
more drop in KWH on my Sept bills on. - WRONG

My electric bill went UP 15% more KWH than the previous year. �I called
National Grid to complain that the meter had to be screwed up or something
because I know they do not estimate in my area. �They have meters with those

They list on the My Bill part of the webpage if the bill is estimated,
and I too have the radio meter, so either they just have to drive by,
or they don't even have to leave the office.

The online bills here are just pdf files that are identical to the
printed bills that they mail, but I have the printed bills too. �I
just have to find them all and put them in order.

electronic devices so the people reading don't even have to leave the car to
get a reading unless the radio is dead. �Since I am never estimated and the
biggest energy wasters (the kids) are not home for 8+ hours a day now and
there had been no change in appliances or other factors there is no way it
could have gone up.

Yes, your story does sound a lot like my story. � Even if the details
are different.

Since I don't know what National Grid is, you're probably not in
Baltimore (which is where I am), but the purpose of conventions is
partly to share trade secrets.

They said that they doubted it because everyone elses bills went up in usage

Why would anyone's usage in KwH go up, unless it was colder in the
winter or hotter in the summer than normal? �I guess plasma tv's use
more electricity and bigger screens use more, but none of this affects
every home or could equal 15% for anyone.

about that amount so mine should have. �Then I hit them with "Did everyone
else's family start leaving their house vacant for over 45+ more hours a
week than mine?" �Of course not so they started to make even more excuses as
far fetched as "sun spots" affecting my usage.

I really think that the do something very fishy there because I complained a
few times and they said they were not going to check unless there was a
drastic circumstance that they could know 100% that something was wrong. �I
lied and I said that I was going away on vactaion for 3 week in March and
turning off the fridge, not using the dryer, the water pump, TV or even
leaving lights on so my bill should be squat.

Good idea to tell them that.

And btw, if I do go away next year, I think I'll turn off the
refrigerator. � I think I froze a half gallon of milk just before I
left, and drank it when I got home, but with a trifle extra planning,
there doesn't have to be any food left to spoil. � If I go for Feb,
March, and April (a possibility**) and the furnace is set at 45, I
would think it wouldn't run at all the last month or two. � Then there
should be almost nothing on.

I'm going to have to start verifying the meter readings also. � Maybe
in general and before and after the trip. �There are many far more
important reasons to go on this trip, (and to stay home) but somehow
the notion of checking up on them seems very important right now.

Well guess what? �I did not go away and they did not say they came out, but
right after I told them that something was coming up that was going to nail
them on a busted meter or a screw up, my bills since then went dow about the
expected 20%. �Isn't that amazing. �

Quite amazing. �Sounds hinky.

� � �NOT, I"m sure you mean.

I am doing anything more than I was
before, but all of a sudden after the threats my bills magically drop the
20%.

I would have emailed you a copy, to make sure you saw this, but no big
deal.

**This time I'm going to try to rent a room in someone's apartment. I
don't know yet how much that would cost, maybe 300 or 400 a month?
Maybe young people. �(If I were a little younger than I am, I could
date their friends.)

The last trip, for 9 weeks, cost me 5000 dollars for everything for
one person, including airfare, a 250 dollar camera and a 150 dollar
camera, and a professional 3-day/2-night tour to some historical city.
I know some people spend 5000 for a 2 weeks. �



"mm" wrote in message
.. .
On Thu, 07 Aug 2008 05:36:26 -0700, Smitty Two
wrote:

In article ,
mm wrote:

On Wed, 06 Aug 2008 20:09:53 -0700, Smitty Two
wrote:

There is one caveat. If your water heater is so poorly insulated or so
unfavorably situated that the water temp inside returns to supply
ambient before those ten hours elapse, then you'll save. Since you're
obviously energy conscious, that caveat likely doesn't apply.

I've turned off the electricity to my water heater and it stays pretty
hot for 3 days iirc. � And it would stay hot a lot longer if I weren't
using the hot water. �The major thing cooling off the water is the
cold water going in when I use hot water.

Usage is very strange. �I went away for November and December (and my
billing periods were from the 15th to the 14th, and my bill was almost
the same as the previous year when I was here the whole time.

The water heater was off, and empty. The furnaace was down to about 45
and it's oil so it only used electricity to run the ignition and
blower, and the furance fan.

About 4 lights were on timers, but I leave 3 of them on timers even
when I'm home.

It was not an estimated reading.

I still haven't figured it out.

We love a good mystery. I'm sure you know that for comparison, it's
kilowatt-hours that count, not dollars. How old is that refrigerator?

Yeah, I forgot to say that I compared KwH, not dollars.

The fridge is only 29 years old, but when I was away, I didn't open
the door at all, so however high the electric usage it was, it should
have been less, a lot less, when I was away.

If I'm lucky I may go away for 2 months March and April of next
year**. �I'll try to do a better job, if possible, of comparing then

**Prior to last years trip I hadn't been anywhere except to visit my
brother in 10 years. Plus I'm trying to sell a project on these trips
(but haven't attempted to deduct even a fraction of the costs. I don't
think I can since I've not gotten any revenue.)- Hide quoted text -

- Show quoted text -

parasitic loads like cable and satellite boxes, doorbells, clocks and
timers, can really add up. some estimate such loads are 25% of ntire
homes power usage

On Sat, 9 Aug 2008 20:14:52 -0700 (PDT), "
wrote:



parasitic loads like cable and satellite boxes, doorbells, clocks and
timers, can really add up. some estimate such loads are 25% of ntire
homes power usage

I left my DSL modem on the last time, because I had a friend ocming in
to dl my email. And I left in such a rush at the end (after having 6
months to pack) that I didn't unplug as many clocks and wall warts as
I might have. I'm saving your list and I"ll do better next time.

Then in May, I drove to Texas and spent off and on two hours looking
for my trailer draw bar, and the ratchet-straps I bought. The draw bar
is an unusual size and I was lucky to track down another one in
Florida and have it mailed to me 2-day mail to Texas. The only good
thing is that I've been back 10 weeks and haven't come across any of
the things I couldn't find before I left. I still haven't plugged
in the AC for the cordless phone that I unplugged to save money.

mm wrote:
On Sat, 9 Aug 2008 20:14:52 -0700 (PDT), "
wrote:


parasitic loads like cable and satellite boxes, doorbells, clocks and
timers, can really add up. some estimate such loads are 25% of ntire
homes power usage

I left my DSL modem on the last time, because I had a friend ocming in
to dl my email. And I left in such a rush at the end (after having 6
months to pack) that I didn't unplug as many clocks and wall warts as
I might have. I'm saving your list and I"ll do better next time.

Then in May, I drove to Texas and spent off and on two hours looking
for my trailer draw bar, and the ratchet-straps I bought. The draw bar
is an unusual size and I was lucky to track down another one in
Florida and have it mailed to me 2-day mail to Texas. The only good
thing is that I've been back 10 weeks and haven't come across any of
the things I couldn't find before I left. I still haven't plugged
in the AC for the cordless phone that I unplugged to save money.
Hi,
Any electronics device is often left plugged in to minimize unwanted
failure.
Failure rate is high when they are starting or stopping. To save a few
bucks, you can end up blowing up a couple hundred bucks worth of a
device. When I was an EIC for a big, big, major data center the system
never got shut down altogether unless there is an absolute reason.
(testing or upgrade, etc.) If we shut down the total system, stabilizing
room temperature, bringing up all the sub systems, always ran into minor
or major component failure(s). Reminds me of penny wise, pound foolish.
I leave everything in the house in stand by or hybernate mode. Never
unplug them. Doing this as long as I remember, nothing bad happened.

On Aug 9, 11:52*am, " wrote:
On Aug 9, 11:10 am, wrote:





On Aug 9, 10:39 am, Smitty Two wrote:

In article
,

wrote:
By
keeping the water heater from coming on during the night and reheating
itself, energy is saved. Period.

We're debating too many issues at once, here, and I'm growing annoyed,
too. You think I'm crazy, I think you are. So I'm going to address this
one issue and ask you one question, and then I'm done with this thread.

I want you to set aside the agreed upon fact that water cools more
slowly as the delta t drops. (We clearly disagree on how significant
that is, in the real world water heater example. Fine, just please set
it aside for the sake of this one question.)

And I want you to set aside any notion that someone may get up in the
night and wash his hands, or that someone get up and take a shower
before the tank has fully recovered.

Now given those constraints, suppose the water in the tank drops by 15
degrees overnight. Do you think it takes less energy to heat the water
in the morning by the whole fifteen degrees, than it would take to
reheat the water three times during the night, each time it drops 5
degrees?

This is a YES or NO question!

That's a simple and straightforward questioned answered by physics.
And the answer is yes. Because by reheating it every time it drops 5
degrees, the water is maintained at a higher temp all night resulting
in more heat loss from the tank to the surroundings.- Hide quoted text -

- Show quoted text -

my old gas heater devloped a leak at the top, so I turned it off till
morning.

turned it on for a quick shower in the morning.

water still nice and hot.

before buying timer first step should be checking how much water cools
over nite.

then go from there.- Hide quoted text -

- Show quoted text -

any modern water heater will keep the water hot for a looong time. the
fact that they're not warm to the touch is another indication. given
the massive heat capacity of water and the minimal loss, there's not a
lot of reason for a timer unless you're trying to schedule for lower
electric rates at night or something.

FWIW, I have a small 67-litre/18 gallon, 1.5 kW/120-volt electric
water heater that pre-heats the supply feed to my indirect oil-fired
tank and my watt meter tells me the standby losses are a little less
than a 1.0 kWh per day. The exterior surface area of this tank is
roughly half that of a standard size model so, in theory, its losses
would be likewise about half. Then again, it's not as well insulated
and I keep the thermostat set at 70°C/160°F so, on that basis, I'd
expect the losses of a conventional tank to be more-or-less similar.

Why keep the tank set so high? Basically, to reduce the likelihood
that this water will be contaminated with legionella bacteria. To
whit:

"The optimal temperature for Legionella proliferation in water varies
between 32°C and 35°C [90° - 95°F], but it can easily proliferate at
temperatures of up to 45°C. Usually, there is no growth above 55°C,
and a temperature of over 60°C has a bactericidal effect. Thus, the
WHO recommends that water be heated and stored at 60°C. However,
studies in Quebec have shown, even when the thermostat is set at 60°C,
a high percentage (approximately 40%) of electric water heaters remain
contaminated because of the lower temperature, about 30°C to 40°C at
the bottom of the tank. The probability of contamination will increase
considerably if the temperature setting is lowered to 49°C."

Source:
http://www.pubmedcentral.nih.gov/art...?artid=2094925

Once established, legionella is, practically speaking, impossible to
eradicate.

Cheers,
Paul