tim.... wrote:
"The Natural Philosopher" wrote in message
...
tim.... wrote:
"Tim Watts" wrote in message
...
Piers Finlayson
wibbled on Monday 05 July 2010 09:02


Of course, heat pumps depend on large amounts of (grid provided)
electricity. I seem to recall something like 1/4 to 1/3 of the total
overall heat energy produced by a heat pump needs to be provided with
electricity to power it.

Given the state of our generating infrastructure in this country I
would not want to be dependent on relatively cheap (and available!)
electricity for my heating in the medium and long term.
I was talking to an air-con engineer last Saturday. He was saying that,
according to the contact he's had with manufacturers and various
seminars,
that the big push is to get air source pumps into a viable state as it
is
well recognised that ground source is too expensive and/or difficult for
the
majority to adopt.

Apparently, they have air source producing useful output at air
temperatures
slightly below freezing and producing useful temperatures on the output
side, so as always the effort is to make it viable commercially.

It sounded potentially quite promising. Not sure if it's going to be a
matter of years or a decade, but watch this space...
Surely this only works for cooling. The outside air is normally going to
be colder than the inside air so this is a cheaper way to cool the
inside.

It is never going to work for heating up a house (except in some very
extreme outside conditions that I think we can ignore)

I dont think you understand what a heat pump is.

I think I do (BICBW)

Thats like saying a fridge only works if the room is at -5C..

No, because you can run the fridge down to -5 by putting more power in.

The idea of an "efficient" heat pump is that you use less power to "extract"
the heat from somewhere else that you would use to heat up the place
instead.


Fraid you still dont get the point.

A heat pump will pump in a single stage about 40 degrees C at about 4:1
uplift in power in to power out of the hot end. It will do about 50C at
about 3:1. You can do more with multiple stages.

So it doesn't matter what the outside temperature is, as long as the
working fluid doesn't freeze, it works.

What matters is that below about -10C, its barely able to get the output
up to 30C. You need a two stage pump, or simply add top up resistive
heating.



tim

Tim Streater wrote:
In article ,
The Natural Philosopher wrote:

tim.... wrote:
"Arfa Daily" wrote in message
news:NCiYn.44629$cJ6.42108@hurricane...
Yes, I'm a little unclear as to what exactly the objections are
to nuclear power generation.
For me it's the (apparent) completely open ended costs of
disposal. If the private sector is going to be allowed to build
nuclear power stations they have to factor in the total cost of
decommissioning into their kWh price, but they can't.

They do, and they can. The problem is that no one has actually defined
exactly what decomissioning means. Currently 15% of build cst is set
aside for decommissioning, BUT teh government refuses to say whether
at some later date it might just decide to change the rules, and make
the companies liable for wrapping the whole things in cotton candy and
having the board of directors lick it all off.

I mean, should a coal fired station have to spend the totality of its
profit fixing the carbon its used, back into coal?

Having spent a lot of money concentrating radioactive ores to get
decent fission, just grinding the ores up and scattering them back in
uranium mines where they came from is deemed unacceptable. In fact
nothing satisfies the green ****ers.

The easiest way to decommission a reactor is take the high level waste
out, reprocess that, and then fill the sodding thing with a decent
concrete, and leave it for 500 years. But that is not satisfactory
apparently, either.

On a decent times scale, nuclear power is removing net radioactivity
from the planet.

They should get medals.

Only from the surface, though, really. The earth's core is molten
because of the uranium and other heavy elements, that, when the whole
planet was molten, simply sank to the middle. Which is why the core of
the earth is iron [1] with added radioactive elements, keeping the
******* hot. Very hot. [2]


well actually the earth is simply cooling down internally. The
radioactivity merely slows it a bit.

The green party will be putting the Sun out when it gets to power, on
account of all the radiation it produces, so no need for an atmosphere
after that.


[1] Just as well so we have a magnetic field protecting us from the
solar wind that would otherwise trip the atmosphere off.

[2] also just as well so we get plate tectonics that is useful for life.

"tim...." wrote in message
...

"The Natural Philosopher" wrote in message
...
tim.... wrote:
"Tim Watts" wrote in message
...
Piers Finlayson
wibbled on Monday 05 July 2010 09:02


Of course, heat pumps depend on large amounts of (grid provided)
electricity. I seem to recall something like 1/4 to 1/3 of the total
overall heat energy produced by a heat pump needs to be provided with
electricity to power it.

Given the state of our generating infrastructure in this country I
would not want to be dependent on relatively cheap (and available!)
electricity for my heating in the medium and long term.
I was talking to an air-con engineer last Saturday. He was saying that,
according to the contact he's had with manufacturers and various
seminars,
that the big push is to get air source pumps into a viable state as it
is
well recognised that ground source is too expensive and/or difficult
for the
majority to adopt.

Apparently, they have air source producing useful output at air
temperatures
slightly below freezing and producing useful temperatures on the output
side, so as always the effort is to make it viable commercially.

It sounded potentially quite promising. Not sure if it's going to be a
matter of years or a decade, but watch this space...

Surely this only works for cooling. The outside air is normally going
to be colder than the inside air so this is a cheaper way to cool the
inside.

It is never going to work for heating up a house (except in some very
extreme outside conditions that I think we can ignore)


I dont think you understand what a heat pump is.

I think I do (BICBW)

Thats like saying a fridge only works if the room is at -5C..

No, because you can run the fridge down to -5 by putting more power in.

The idea of an "efficient" heat pump is that you use less power to
"extract" the heat from somewhere else that you would use to heat up the
place instead.

Normally any power you put in also arrives at the heating side (excluding
the fan on ASHP).
So even if you put in more power they still work and still give out more
heat than the input.
Or at least they do until they have a complete covering of ice which acts as
an insulator to some extent.
I wonder why they don't have a flat plate with a scraper/de-icing boot to
remove the ice?

tim

On Jul 5, 11:15*am, The Natural Philosopher
wrote:
Huge wrote:
On 2010-07-05, Tim Watts wrote:
Huge
* wibbled on Monday 05 July 2010 10:32
On 2010-07-05, Tim Watts wrote:


Good point. I only have direct experience of my Mother's house, which was (she
now lives in a retirement community) in Pennsylvania. Much colder than the UK
in the winter and much, much hotter in the summer. The heat pump ran both
the heating and air-con. All the houses on the estate she lived on had
them - the only energy source was electricity. When it was substantially
below freezing, she had to switch to pure resistive heating, since the heat
pump would ice up.

Aye, and there's the rub.

Ground source is far more useful as teh overall land temperature varies
less.

The best approach on a new build is to use the ground under the house,
and the plot..pumping heat into it in summer using the system as aircon,
and out again in winter using a heat pump.

In summer you can do it simpler and with less energy by just running
under-house cool air through a fanned heat exchanger.


NT

On Tue, 6 Jul 2010 08:53:04 +0100, dennis@home wrote:

I wonder why they don't have a flat plate with a scraper/de-icing boot
to remove the ice?

'cause users would get fed up going out every hour or so to scrape
the ice off. Easier for the control system to monitor the thing and
run the heat pump in the other direction to thaw the ice build up.

--
Cheers
Dave.

On 5 July, 23:18, The Natural Philosopher
wrote:

well actually the earth is simply cooling down internally. The
radioactivity merely slows it a bit.

Do the numbers - Kelvin did a century ago, and that ought to be within
your timescale.

On 6 July, 08:53, "dennis@home" wrote:

Or at least they do until they have a complete covering of ice which acts as
an insulator to some extent.
I wonder why they don't have a flat plate with a scraper/de-icing boot *to
remove the ice?

Countries that use heat pumps, and have cold enough winters that they
care about this stuff, generally also have dry winters and so this
form of icing isn't a big problem.

It's also a further encouragement to use ground source pumps, rather
than air source.

"Dave Liquorice" wrote in message
ll.co.uk...
On Tue, 6 Jul 2010 08:53:04 +0100, dennis@home wrote:

I wonder why they don't have a flat plate with a scraper/de-icing boot
to remove the ice?

'cause users would get fed up going out every hour or so to scrape
the ice off. Easier for the control system to monitor the thing and
run the heat pump in the other direction to thaw the ice build up.

Why would they need to go and do it?

Mechanically removing the ice means you have extracted the latent heat.

tim.... wrote:

For me it's the (apparent) completely open ended costs of disposal. If the
private sector is going to be allowed to build nuclear power stations they
have to factor in the total cost of decommissioning into their kWh price,
but they can't.



I don't think there are any energy sources that are adequate for our
civilisation and are factoring in the true costs. Nuclear is closer
than most.

No fossil fuel system is factoring in the costs of the environmental
damage that most people accept is being caused by uncontrolled release
of carbon dioxide and other pollutants.

Andy

Andy Champ wrote:
tim.... wrote:

For me it's the (apparent) completely open ended costs of disposal.
If the private sector is going to be allowed to build nuclear power
stations they have to factor in the total cost of decommissioning into
their kWh price, but they can't.



I don't think there are any energy sources that are adequate for our
civilisation and are factoring in the true costs. Nuclear is closer
than most.

No fossil fuel system is factoring in the costs of the environmental
damage that most people accept is being caused by uncontrolled release
of carbon dioxide and other pollutants.

Andy

Exactly.

The green position is 'all pollution Bad. So, no nuclear no fossil, =no
people.

Cos the job cant be done with current levels of population AND totally
renewable technology.

Energy s all about turning low entropy materials (coal, gas, oil,
uranium) into high entropy waste (hot carbon dioxide, hot air, hot
radioactive materials).

Its always been a source of mystery to me why a dirty radioactive planet
will be 'saved' by using JUST the energy off a dirty radioactive
sun...that is anything BUT renewable.

NT wrote:
On Jul 5, 1:35*pm, wrote:
NT wrote:
The energy return is really a red herring. Money return is what
counts, its not as if we're short of energy.

Money is merely a cultural artefact, and can be made in any
desired quantity. *Clearly, it far surpasses 1kW/m2 on the
earth's disk in its intrinsic value.

The value of money is what counts, ie what it can purchase. Printing
it just gives more units worth less per unit.

Worth less of what, exactly? Other money? The values
we place on physical and non-physical artefacts are culturally
determined, and we exchange these artefacts with yet
another virtual non-physical cultural artefact ("money").

The economy is largely a giant hallucination with no real
physical existence. After all, we are in some kind of
credit crunch or recession, but it's not because we are
suddenly short of energy or materials or skilled humans
or food supplies or because we're all watching the footy
rather than doing or making something. We're in a hallucinated
recession because the hallucination tells us we are.

With 1W/m2 I could probably do some useful work. With £1
I have to pull a con trick on a suitably deluded passerby.

#Paul

On Tue, 6 Jul 2010 20:10:37 +0100, dennis@home wrote:

I wonder why they don't have a flat plate with a scraper/de-icing
boot
to remove the ice?

'cause users would get fed up going out every hour or so to scrape
the ice off.

Why would they need to go and do it?

Ice is a pretty good insulator. An iced up heat collector is no
longer in contact with the nice, releatively warm, moving air from
which to extract more heat.

Mechanically removing the ice means you have extracted the latent heat.

True you but once frozen you have extracted that latent heat and you
now have an insulating layer on your collector.

--
Cheers
Dave.

On Jul 6, 11:20*pm, wrote:
NT wrote:
On Jul 5, 1:35 pm, wrote:
NT wrote:


The energy return is really a red herring. Money return is what
counts, its not as if we're short of energy.

Money is merely a cultural artefact, and can be made in any
desired quantity. Clearly, it far surpasses 1kW/m2 on the
earth's disk in its intrinsic value.

The value of money is what counts, ie what it can purchase. Printing
it just gives more units worth less per unit.

Worth less of what, exactly? *Other money?

less ability to buy goods & services.


*The values
we place on physical and non-physical artefacts are culturally
determined, and we exchange these artefacts with yet
another virtual non-physical cultural artefact ("money").

The economy is largely a giant hallucination with no real
physical existence. *After all, we are in some kind of
credit crunch or recession, but it's not because we are
suddenly short of energy or materials or skilled humans
or food supplies or because we're all watching the footy
rather than doing *or making something. We're in a hallucinated
recession because the hallucination tells us we are.

.... And yet money & the recession are no less real

With 1W/m2 I could probably do some useful work. *With 1
I have to pull a con trick on a suitably deluded passerby.

#Paul


NT

On Jul 7, 8:00*am, "Dave Liquorice"
wrote:
On Tue, 6 Jul 2010 20:10:37 +0100, dennis@home wrote:
I wonder why they don't have a flat plate with a scraper/de-icing
boot
to remove the ice?

'cause users would get fed up going out every hour or so to scrape
the ice off.

Why would they need to go and do it?

Ice is a pretty good insulator. An iced up heat collector is no
longer in contact with the nice, releatively warm, moving air from
which to extract more heat.

Mechanically removing the ice means you have extracted the latent heat.

True you but once frozen you have extracted that latent heat and you
now have an insulating layer on your collector.

I've sometimes wondered why heat exchangers on refrigeration arent
made partly from bimetal or designed asymmetrically so that they move
slightly with each run cycle, helping to reduce ice build up to some
degree.


NT

"Dave Liquorice" wrote in message
ll.co.uk...
On Tue, 6 Jul 2010 20:10:37 +0100, dennis@home wrote:

I wonder why they don't have a flat plate with a scraper/de-icing
boot
to remove the ice?

'cause users would get fed up going out every hour or so to scrape
the ice off.

Why would they need to go and do it?

Ice is a pretty good insulator. An iced up heat collector is no
longer in contact with the nice, releatively warm, moving air from
which to extract more heat.

Mechanically removing the ice means you have extracted the latent heat.

True you but once frozen you have extracted that latent heat and you
now have an insulating layer on your collector.

Which is why you need the scraper and/or de-icing boot.

Tim Streater wrote:
With 1W/m2 I could probably do some useful work. With ?1
I have to pull a con trick on a suitably deluded passerby.

So go back to a barter economy then and see how far you get.

I'm not saying money isn't a handy concept to have. But
that doesn't mean its value isn't entirely imaginary.

#Paul

wrote:
Tim Streater wrote:
With 1W/m2 I could probably do some useful work. With ?1
I have to pull a con trick on a suitably deluded passerby.

So go back to a barter economy then and see how far you get.

I'm not saying money isn't a handy concept to have. But
that doesn't mean its value isn't entirely imaginary.


when you get down to it, modern physics and philosophy could say that
about everything else too.

#Paul

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember saying
something like:

The economy is largely a giant hallucination with no real
physical existence. After all, we are in some kind of
credit crunch or recession, but it's not because we are
suddenly short of energy or materials or skilled humans
or food supplies or because we're all watching the footy
rather than doing or making something. We're in a hallucinated
recession because the hallucination tells us we are.

This one's rumbled it.
Keelll heem, before he tells others and ruins it.

On Jul 5, 12:17*pm, Huge wrote:
On 2010-07-05, Arfa Daily wrote:

so what is it about them [nuclear reactors] that scares people?

I think it all comes down to the fundamental anti-science bias of our
current society.

The metropolitan, guardian reading, middle classes, especially. Throw
in "celebritie" such as Carol Vordeman jumping on things like the anti-
MMR bandwagon and you can see why we're in such a mess.

The Guardian does, however, carry the excellent Bad Science column.

MBQ

On Jul 5, 8:08*pm, "tim...." wrote:
"Arfa Daily" wrote in message

news:NCiYn.44629$cJ6.42108@hurricane...



Yes, I'm a little unclear as to what exactly the objections are to nuclear
power generation.

For me it's the (apparent) completely open ended costs of disposal.

I'm more worried by the apparently open ended cost of public sector
final salary pensions. Anything else pales into (almost)
insignificance.

MBQ

On Jul 5, 1:35*pm, wrote:
NT wrote:
The energy return is really a red herring. Money return is what
counts, its not as if we're short of energy.

Money is merely a cultural artefact, and can be made in any
desired quantity. *

Let's just burn money then, simples!

MBQ

On Jul 5, 11:26*am, Tim Streater wrote:
In article ,
*The Natural Philosopher wrote:



Huge wrote:
On 2010-07-05, Tim Watts wrote:
Huge
* wibbled on Monday 05 July 2010 10:32

On 2010-07-05, Tim Watts wrote:

I was talking to an air-con engineer last Saturday. He was saying that,
according to the contact he's had with manufacturers and various
seminars, that the big push is to get air source pumps into a viable
state as it is well recognised that ground source is too expensive
and/or difficult for the majority to adopt.

Apparently, they have air source producing useful output at air
temperatures slightly below freezing and producing useful temperatures
on the output side, so as always the effort is to make it viable
commercially.

It sounded potentially quite promising. Not sure if it's going to be a
matter of years or a decade, but watch this space...
Given that air source heat pumps are routinely installed in the USA, I
don't really understand what the issue is.

Which bits of the USA though? Cold northern areas or generally warmer
southern climes?

Good point. I only have direct experience of my Mother's house, which was
(she *now lives in a retirement community) in Pennsylvania. Much colder
than the *UK in the winter and much, much hotter in the summer. The heat
pump ran both the heating and air-con. All the houses on the estate she
lived on had them - the only energy source was electricity. When it was
substantially below freezing, she had to switch to pure resistive heating
, since the heat pump would ice up.

Aye, and there's the rub.

Air source is supposed to be OK down to a few deg.

Ground source is far more useful as teh overall land temperature varies
less.

There is a limit to what you can take out as the heat you remove from
the ground (in winter) is replenished by conduction from adjacent ground
(it's not geothermal).

Why did you snip "pumping heat into it in summer using the system as
aircon"?

MBQ

Tim Streater wrote:

Media-fuelled ignorance doesn't help. Yesterday morning (I think it was)
there was a piece about waste storage on the Today programme. Even they
repeated the old canard about "some of this waste has a half-life of
millions of years" without apparently understanding that this means that
it's *less*, not *more*, radioactive.

What is the half life of the Universe?

well yes.

essntially if its hot enough to be dangerous, its worth reprocessing and
burning.

That's as far as fuel rods go.

The more contentious issues are what to do with a mildly radioactive
reactor housing that is full of strange isotopes of reinforced concrete,
due to radiation absorption, that's probably pretty safe, but is not
something you would want to live inside for the next 500 years.

really, if politics and paranoia didn't get in the way, you would simply
fill them up with concrete cover with soil.. and leave them..for 500
years. A sort of modern Stonehenge to be puzzled over by archaeologists
in 2500 years..but that doesn't satisfy the greenies, so no one has
really come up with a solution.

If you cut them up, you have to them move them somewhere else, and do
the same. Which in itself releases far more radiation than is needful.
And introduces unnecessary risks in transportation and dismantling.

Tim Streater wrote:
In article ,
The Natural Philosopher wrote:

Tim Streater wrote:
Media-fuelled ignorance doesn't help. Yesterday morning (I think
it was) there was a piece about waste storage on the Today
programme. Even they repeated the old canard about "some of this
waste has a half-life of millions of years" without apparently
understanding that this means that it's *less*, not *more*,
radioactive.
What is the half life of the Universe?

well yes.

essntially if its hot enough to be dangerous, its worth reprocessing
and burning.

That's as far as fuel rods go.

The more contentious issues are what to do with a mildly radioactive
reactor housing that is full of strange isotopes of reinforced
concrete, due to radiation absorption, that's probably pretty safe,
but is not something you would want to live inside for the next 500
years.

really, if politics and paranoia didn't get in the way, you would
simply fill them up with concrete cover with soil.. and leave
them..for 500 years. A sort of modern Stonehenge to be puzzled over by
archaeologists in 2500 years..but that doesn't satisfy the greenies,
so no one has really come up with a solution.

If you cut them up, you have to them move them somewhere else, and do
the same. Which in itself releases far more radiation than is needful.
And introduces unnecessary risks in transportation and dismantling.

Dump it in a deep ocean trench. It will then be subducted into the mantle.


Oh indeed, but the greenies wont have that either.

In short the green position on old nuclear reactors is

1/. You can't leave that there
2/. You can't put that anywhere else,. either.
3/. Nuclear energy is unlimitedly expesnsive because no one has yet come
up with a decomissioning solution that satisfies 1/. and 2/.
4/. Ergo all nuclear power must be stopped, because of the 'waste problem'

All other lines of attack having failed.

On Jul 8, 12:34*pm, Tim Streater wrote:
In article
,
*"Man at B&Q" wrote:

On Jul 5, 11:26*am, Tim Streater wrote:
In article ,
Ground source is far more useful as teh overall land temperature varies
less.

There is a limit to what you can take out as the heat you remove from
the ground (in winter) is replenished by conduction from adjacent ground
(it's not geothermal).

Why did you snip "pumping heat into it in summer using the system as
aircon"?

Because I wasn't responding to that aspect of the matter.

But it is relevant to your response about replenishing what you take
out.

MBQ

The Natural Philosopher wrote:


frankly, provided its below critical mass..i.e. you ripped out the fuel
rods and sorted them out for reprocessing, or ground em up and dsipersed
them down some suitable mine - filling what's left with cement and
leaving it is a very low cost and safe option.

Complete and utter ********.

On 08/07/2010 11:59, Man at B&Q wrote:
On Jul 5, 12:17 pm, wrote:
On 2010-07-05, Arfa wrote:

so what is it about them [nuclear reactors] that scares people?

I think it all comes down to the fundamental anti-science bias of our
current society.

The metropolitan, guardian reading, middle classes, especially. Throw
in "celebritie" such as Carol Vordeman jumping on things like the anti-
MMR bandwagon and you can see why we're in such a mess.

The Guardian does, however, carry the excellent Bad Science column.

MBQ

Of course ONLY truly independent experts can be believed and that
excludes anyone who works for an "official" or public body or has ever
received grants from an Official body ! ie all the scientific experts
around .

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Man at B&Q"
saying something like:

They can't decide not to dispose of nuclear waste left behind by a bankrupt
power company

Ah! A lot of impoverished public sector pensioners could be gainfully
employed to do the cleaning up.

Save in the cost of PPE and they die early.

Win-win, in my view.

Arfa Daily wrote:

Fling the bloody stuff out in space, that's what I say ! Take a
container-full up in the space shuttle, then push it off in the general
direction of the sun. Gravity will get it in the end. Doesn't really
matter whose, as long as it's not the earth's ... :-)

That's not a good solution. Two reasons:

(1) It's expensive to get heavy stuff into orbit.

(2) Challenger.

Andy

Man at B&Q wrote:
On Jul 5, 1:35*pm, wrote:
NT wrote:
The energy return is really a red herring. Money return is what
counts, its not as if we're short of energy.

Money is merely a cultural artefact, and can be made in any
desired quantity. *

Let's just burn money then, simples!

Do you get more useful work when burning money,
than was required to make it?

#Paul