On Mon, 10 Dec 2018 10:41:08 -0000, The Natural Philosopher wrote:

On 10/12/2018 09:20, Tim Streater wrote:
In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Well if you count a hydrogen explosion that happened because the staff
were not allowed too vent the hydrogen to the atmopshere because it
might be slightly radioactive...

I'm guessing the explosion was a damn big venting. DOH! Health and softy shooting itself in the foot yet again!

On Mon, 10 Dec 2018 09:22:20 -0000, Tim Streater wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

Whatever happened to those AA nuclear batteries? I assume they worked the same.

On Mon, 10 Dec 2018 09:20:58 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:


We do have nuclear power stations which can and do explode....

Wrong.

Nope, Dim, for once the unwashed Scottish ****** was right, you senile
sucker of troll cock!

On Mon, 10 Dec 2018 09:22:20 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

You've certainly turned out to be one the most devoted suckers of the
unwashed Scottish ******'s cock, senile Dim! LOL

On 08/12/2018 22:59, Andrew Gabriel wrote:
In article ,
Clive Arthur writes:
On 08/12/2018 17:51, Bruce Farquhar wrote:
On Sat, 08 Dec 2018 17:40:57 -0000, wrote:

On 12/8/18 11:41 AM, Bruce Farquhar wrote:
On older boilers (furnaces if you're American), when the heating isn't
actually running (eg. the thermostat says the house is warm enough),
there's no power to the boiler, so how does the pilot light valve stay
open with the tiny voltage (40mV?) and current from the thermocouple?

To *hold* the valve open only requires a small voltage & current. To
*pull* the valve open would require a larger voltage. That's why you
have to "Press & Hold" the manual knob to restart a pilot.

See here for more detail:
https://en.wikipedia.org/wiki/Thermo...pliance_safety

I see, thanks.Â* I thought the "press and hold" was just to keep the
valve open until the thermocouple warmed up.Â* So I'm providing the
effort to open the valve with my thumb.Â* That link states 0.2-0.25A - do
you really get that much current off a thermocouple?

Yes, it's a very low impedance source, a metal to different metal
contact. 10mV 200mA is 50 milliohms. It's only 2mW, but that's a very
small proportion of the pilot flame power.

Indeed - a pilot flame is typically around 250W.

Interesting. I thought that sounded like quite a lot. A quarter of a 1
bar fire? Half the output of a big halogen flood? Found a web site that
says a tea-light is about 50 watts (4 grams per hour), so I guess it's
probably about right.

On Mon, 10 Dec 2018 13:25:54 -0000, Tim Streater wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:20:58 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Are you an ostrich or something?

No, I'm just someone who, unlike you, knows his arse from a hole in the
ground.

Yet you think a nuclear station has never gone wrong.

I don't read the news much,

That much is too apparent.

Not in this case.

but even I know many nuclear power stations have ****ed up.

Three is not "many".

You said never.

Lemme see, 3 mile island

Where no one died or was injured. No external damage.

Chernobyl,

Where less than 100 died from the disaster.

So the radiation left won't hurt anyone or cause any costs or problems? You really are an ignorant fool.

that one in Japan....

Yeah, that one in Japan - for your information that was at Fukushima.
Where no one died and no one was injured.

Tell the Japanese it wasn't a problem. Why do you think it's ok if no injuries or deaths occur? What about future cancers to those nearby? What about the cost of rebuilding everything? What about the damage to wildlife? You really are a stupid ignorant ****.

And, for your information, you should look up "deaths from ordinary
industrial accidents", you'll find the numbers to be much larger.

Only if you take the numbers too literally like you do.

And if your point is to say that nuclear power stations are a good idea, then I agree with you. But they are not completely safe.

On Mon, 10 Dec 2018 13:19:41 -0000, Tim Streater wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:22:20 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed
wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

Whatever happened to those AA nuclear batteries? I assume
they worked the same.

What on earth are you talking about?

Some idea or prototype someone came up with 10 or 20 years ago. They were supposed to be to for use in very long life and low current things - battery backup for alarms, wall clocks, thermostats, etc.

On Mon, 10 Dec 2018 11:16:54 -0000, newshound wrote:

On 08/12/2018 22:59, Andrew Gabriel wrote:
In article ,
Clive Arthur writes:
On 08/12/2018 17:51, Bruce Farquhar wrote:
On Sat, 08 Dec 2018 17:40:57 -0000, wrote:

On 12/8/18 11:41 AM, Bruce Farquhar wrote:
On older boilers (furnaces if you're American), when the heating isn't
actually running (eg. the thermostat says the house is warm enough),
there's no power to the boiler, so how does the pilot light valve stay
open with the tiny voltage (40mV?) and current from the thermocouple?

To *hold* the valve open only requires a small voltage & current. To
*pull* the valve open would require a larger voltage. That's why you
have to "Press & Hold" the manual knob to restart a pilot.

See here for more detail:
https://en.wikipedia.org/wiki/Thermo...pliance_safety

I see, thanks. I thought the "press and hold" was just to keep the
valve open until the thermocouple warmed up. So I'm providing the
effort to open the valve with my thumb. That link states 0.2-0.25A - do
you really get that much current off a thermocouple?

Yes, it's a very low impedance source, a metal to different metal
contact. 10mV 200mA is 50 milliohms. It's only 2mW, but that's a very
small proportion of the pilot flame power.

Indeed - a pilot flame is typically around 250W.

Interesting. I thought that sounded like quite a lot. A quarter of a 1
bar fire? Half the output of a big halogen flood? Found a web site that
says a tea-light is about 50 watts (4 grams per hour), so I guess it's
probably about right.

Common sense tells us it can't be. A quarter of a 1 bar fire would make the water in the boiler pretty warm! Now remember that at this point the pump isn't running, so that heat can't easily move to the radiators. The boiler would get piping hot pretty quickly. My medium sized gas boiler is rated 4-12kW (depending on the gas pressure setting), which would mean it's still using up to a 16th of the gas when turned off! That would be truly absurd. The only thing as stupidly inefficient as that is a Sky satellite TV box which uses precisely the same 38W when in standby as when switched on!

On Mon, 10 Dec 2018 15:33:33 -0000, Tim Streater wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 13:25:54 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:20:58 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Are you an ostrich or something?

No, I'm just someone who, unlike you, knows his arse from a hole in the
ground.

Yet you think a nuclear station has never gone wrong.

I have never said this.

I said "We do have nuclear power stations which can and do explode...."
You said "Wrong."

but even I know many nuclear power stations have ****ed up.

Three is not "many".

You said never.

When?

Lemme see, 3 mile island

Where no one died or was injured. No external damage.

Chernobyl,

Where less than 100 died from the disaster.

So the radiation left won't hurt anyone or cause any costs or problems? You
really are an ignorant fool.

That's a different issue.

But still very significant.

that one in Japan....

Yeah, that one in Japan - for your information that was at Fukushima..
Where no one died and no one was injured.

Tell the Japanese it wasn't a problem. Why do you think it's ok if no
injuries or deaths occur?

Because it already tells us a lot.

So if my car crashed due to a fault and didn't hurt me, that would be ok for me to have to pay out £1000s for repairs?

What about future cancers to those nearby?

Who says there will be any?

Everyone.

What about the cost of rebuilding everything?

Rebuilding what? As it happens, the Fukushima plant was due to be
closed within 6 months of the incident anyway - end of life.

And no damage was caused by the reactors. All the damage was from the
tsunami, which caused some 25,000 deaths. Perhaps you should be
concerned about that.

What about the damage to wildlife?

What damage to wildlife?

Radiation will do that.

And, for your information, you should look up "deaths from ordinary
industrial accidents", you'll find the numbers to be much larger.

Only if you take the numbers too literally like you do.

Why shouldn't I take them literally?

Because you're not taking into account other significant problems.

And if your point is to say that nuclear power stations are a good idea,
then I agree with you. But they are not completely safe.

Much, *much* safer than other forms of energy generation.

Agreed, all I'm saying is they do go wrong.

On Mon, 10 Dec 2018 15:50:29 -0000, Tim Streater wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 15:33:33 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

Yet you think a nuclear station has never gone wrong.

I have never said this.

I said "We do have nuclear power stations which can and do explode....."
You said "Wrong."

What was wrong was your implication that they does this often and on a
regular basis.

I said "can and do" - that doesn't mean "often".

Tell the Japanese it wasn't a problem. Why do you think it's ok if no
injuries or deaths occur?

Because it already tells us a lot.

So if my car crashed due to a fault and didn't hurt me, that would be ok for
me to have to pay out £1000s for repairs?

In the case of Fukushima, repairs to what?

So you think no damage was caused? Do I really have to google it for you?

What about future cancers to those nearby?

Who says there will be any?

Everyone.

You mean over and above background?

Clearly.

What about the damage to wildlife?

What damage to wildlife?

Radiation will do that.

As it has been doing since the dawn of time. You are perhaps unaware
that, every second, some 4,000 disintegrations of radioactive nuclei
take place in your body - and mine, and everyone else's. And the body
has mechanism for repairing the damage, which are at work all day every
day.

And the presence of these radioactive atoms has nothing to do with
nuclear power stations or bomb tests. Or Chernobyl.

Go into the restricted zone at Chernobyl without any protection then report back.

On 10/12/2018 15:33, Tim Streater wrote:
So the radiation left won't hurt anyone or cause any costs or
problems?Â* You
really are an ignorant fool.


No, te radiatin that is left will not hurt anyone. Its all nicely
contained as it was supposed to be.

Of courese it will cxause cistr or problems but then soi will trying to
deciomission winmolls on 500 tonne concrete pads to return te sites back
to how they were.

Who will pay for windmill decomissioning? You will and I will.




That's a different issue.


--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

In a so called milliVolt heating system, BOTH the pilot valve and the main gas valve are controlled by low voltage valves.

You need to press and hold the button to light the pilot to give the thermopile a chance to heat up so it can continue to hold the pilot valve open.

The main valve is controlled by the Tstat using the small voltage generated by the thermopile.

I don't know about newer systems with flue dampers etc but the older mVolt systems worked without any grid power at all, all the electricity was generated by the thermopile heated by the pilot light.


mark




The thermopile voltage is very low but the current is high enough to operate the valves that are designed to work on very low voltage.

On Mon, 10 Dec 2018 03:39:31 -0000, Rod Speed wrote:



"Bruce Farquhar" wrote in message
news
On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Those ones used on earth don't.

Funny how some have in the past.

And even you should have noticed that with an unmanned
light house or warning light on the top of a mountain etc
that it's not that easy to stop someone grabbing it and
taking it home to power their remote holiday shack etc.

Yes but what has that to do with this conversation?

Well, since you ask:

[wiki]

In addition to spacecraft, the Soviet Union constructed
many unmanned lighthouses and navigation beacons
powered by RTGs.[5]
......
One RTG, the SNAP-19C, was lost near the top of Nanda
Devi mountain in India in 1965 when it was stored
in a rock formation near the top of the mountain
in the face of a snowstorm before it could be
installed to power a CIA remote automated station
collecting telemetry from the Chinese rocket testing facility.
=======
rest:
https://en.wikipedia.org/wiki/Radioi...tric_generator
On Sat, 08 Dec 2018 21:04:59 -0000, Brian Gaff

wrote:

I'm sure you know this but the Voyager spacecraft are using
thermocouples
using the heat from decaying plutonium for power all the way out in
the
cosmos. it may be reducing now but its been one heck of a long time.

On 10/12/2018 14:32, Bruce Farquhar wrote:
On Mon, 10 Dec 2018 11:16:54 -0000, newshound
wrote:

On 08/12/2018 22:59, Andrew Gabriel wrote:
In article ,
****Clive Arthur writes:
On 08/12/2018 17:51, Bruce Farquhar wrote:
On Sat, 08 Dec 2018 17:40:57 -0000, wrote:

On 12/8/18 11:41 AM, Bruce Farquhar wrote:
On older boilers (furnaces if you're American), when the heating
isn't
actually running (eg. the thermostat says the house is warm enough),
there's no power to the boiler, so how does the pilot light valve
stay
open with the tiny voltage (40mV?) and current from the
thermocouple?

To *hold* the valve open only requires a small voltage & current. To
*pull* the valve open would require a larger voltage. That's why you
have to "Press & Hold" the manual knob to restart a pilot.

See here for more detail:
https://en.wikipedia.org/wiki/Thermo...pliance_safety

I see, thanks.* I thought the "press and hold" was just to keep the
valve open until the thermocouple warmed up.* So I'm providing the
effort to open the valve with my thumb.* That link states 0.2-0.25A
- do
you really get that much current off a thermocouple?

Yes, it's a very low impedance source, a metal to different metal
contact.* 10mV 200mA is 50 milliohms.* It's only 2mW, but that's a very
small proportion of the pilot flame power.

Indeed - a pilot flame is typically around 250W.

Interesting. I thought that sounded like quite a lot. A quarter of a 1
bar fire? Half the output of a big halogen flood? Found a web site that
says a tea-light is about 50 watts (4 grams per hour), so I guess it's
probably about right.

Common sense tells us it can't be.* A quarter of a 1 bar fire would make
the water in the boiler pretty warm!* Now remember that at this point
the pump isn't running, so that heat can't easily move to the
radiators.* The boiler would get piping hot pretty quickly.* My medium
sized gas boiler is rated 4-12kW (depending on the gas pressure
setting), which would mean it's still using up to a 16th of the gas when
turned off!* That would be truly absurd.* The only thing as stupidly
inefficient as that is a Sky satellite TV box which uses precisely the
same 38W when in standby as when switched on!

Oh I don't know. In the dim and distant past, my boiler which had a
pilot light was floor standing and about 0.6 x 0.6 x 1 metre high.
Giving it a surface area of about 2.4 square metres. Much bigger than a
modern boiler I know, but modern boilers don't have them. So, taking a
convective heat transfer coefficient of 10 W/m^2K the surface
temperature rise to dissipate 250 watts if it does not go anywhere else
is about ten degrees C. Warm to the touch but not huge. And I bet 90% of
the energy used to go out of the flue.

In the mid 70's I had a multipoint gas water heater which, IIRC, was 22
kW. The exposed surface was probably only half that of the boiler in the
calculation, but that had a fairly lively pilot light and the casing was
always perceptibly warm to the touch.

On Monday, December 10, 2018 at 10:58:04 AM UTC-6, Bruce Farquhar wrote:

Bruce, learn how to filter or ignore the JO's here. They are baiters/'baters!

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 09:20:58 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Are you an ostrich or something? I don't read the news much, but even I
know many nuclear power stations have ****ed up. Lemme see, 3 mile
island, Chernobyl, that one in Japan....

Only Fukushima exploded.

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 10:41:08 -0000, The Natural Philosopher
wrote:

On 10/12/2018 09:20, Tim Streater wrote:
In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Well if you count a hydrogen explosion that happened because the staff
were not allowed too vent the hydrogen to the atmopshere because it
might be slightly radioactive...

I'm guessing the explosion was a damn big venting. DOH! Health and softy
shooting itself in the foot yet again!

Sure, but it wasn't certain that it would explode if not vented.

On Mon, 10 Dec 2018 17:53:15 -0000, newshound wrote:

On 10/12/2018 14:32, Bruce Farquhar wrote:
On Mon, 10 Dec 2018 11:16:54 -0000, newshound
wrote:

On 08/12/2018 22:59, Andrew Gabriel wrote:
In article ,
Clive Arthur writes:
On 08/12/2018 17:51, Bruce Farquhar wrote:
On Sat, 08 Dec 2018 17:40:57 -0000, wrote:

On 12/8/18 11:41 AM, Bruce Farquhar wrote:
On older boilers (furnaces if you're American), when the heating
isn't
actually running (eg. the thermostat says the house is warm enough),
there's no power to the boiler, so how does the pilot light valve
stay
open with the tiny voltage (40mV?) and current from the
thermocouple?

To *hold* the valve open only requires a small voltage & current.. To
*pull* the valve open would require a larger voltage. That's why you
have to "Press & Hold" the manual knob to restart a pilot.

See here for more detail:
https://en.wikipedia.org/wiki/Thermo...pliance_safety

I see, thanks. I thought the "press and hold" was just to keep the
valve open until the thermocouple warmed up. So I'm providing the
effort to open the valve with my thumb. That link states 0.2-0.25A
- do
you really get that much current off a thermocouple?

Yes, it's a very low impedance source, a metal to different metal
contact. 10mV 200mA is 50 milliohms. It's only 2mW, but that's a very
small proportion of the pilot flame power.

Indeed - a pilot flame is typically around 250W.

Interesting. I thought that sounded like quite a lot. A quarter of a 1
bar fire? Half the output of a big halogen flood? Found a web site that
says a tea-light is about 50 watts (4 grams per hour), so I guess it's
probably about right.

Common sense tells us it can't be. A quarter of a 1 bar fire would make
the water in the boiler pretty warm! Now remember that at this point
the pump isn't running, so that heat can't easily move to the
radiators. The boiler would get piping hot pretty quickly. My medium
sized gas boiler is rated 4-12kW (depending on the gas pressure
setting), which would mean it's still using up to a 16th of the gas when
turned off! That would be truly absurd. The only thing as stupidly
inefficient as that is a Sky satellite TV box which uses precisely the
same 38W when in standby as when switched on!

Oh I don't know. In the dim and distant past, my boiler which had a
pilot light was floor standing and about 0.6 x 0.6 x 1 metre high.
Giving it a surface area of about 2.4 square metres. Much bigger than a
modern boiler I know, but modern boilers don't have them. So, taking a
convective heat transfer coefficient of 10 W/m^2K the surface
temperature rise to dissipate 250 watts if it does not go anywhere else
is about ten degrees C. Warm to the touch but not huge. And I bet 90% of
the energy used to go out of the flue.

In the mid 70's I had a multipoint gas water heater which, IIRC, was 22
kW. The exposed surface was probably only half that of the boiler in the
calculation, but that had a fairly lively pilot light and the casing was
always perceptibly warm to the touch.

I once calculated my gas usage for the pilot light to be £10 a month (at 3.5p a kWh) on my 12kW boiler, as it was the only thing running over the summer. That's a ridiculous cost, no wonder they use electric ignition now. Not sure why they didn't always do that - gas cookers have had spark ignition for at least 40 years, if not more. Even if they didn't have a spark that could operate millions of times, it could always light a pilot and extinguish it if not in use for a certain amount of time.

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 09:22:20 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed
wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

Whatever happened to those AA nuclear batteries?

Never did get used much.
https://en.wikipedia.org/wiki/Atomic_battery

I assume they worked the same.

Some did, some didn't.

On Mon, 10 Dec 2018 18:11:24 -0000, bob_villa wrote:

On Monday, December 10, 2018 at 10:58:04 AM UTC-6, Bruce Farquhar wrote:

Bruce, learn how to filter or ignore the JO's here. They are baiters/'baters!

I get accused of being such a thing too - it's a matter of opinion who should be deleted.

I filter and ignore those that annoy me, some are amusing though.

On 12/10/2018 9:42 AM, Bruce Farquhar wrote:
....

Agreed, all I'm saying is they do go wrong.

But _NO_ commercial reactors have "exploded" from the fuel having had an
uncontrolled chain reaction.

Chernobyl was so destructive because the Russky's didn't build a
containment structure to save $$ and so the fire melted the housing
structure (essentially just a "Butler building") and thus let the smoke
plume disperse the gaseous and light fission products. But, it was a
conventional fire, not a nuclear explosion that was the event.

--

In "Rod Speed" writes:

Whatever happened to those AA nuclear batteries?

Never did get used much.
https://en.wikipedia.org/wiki/Atomic_battery

They sure came in handy on the Batmobile...

("Atomic batteries for power, turbines for speed")


--
__________________________________________________ ___
Knowledge may be power, but communications is the key

[to foil spammers, my address has been double rot-13 encoded]

On Mon, 10 Dec 2018 18:36:44 -0000, dpb wrote:

On 12/10/2018 9:42 AM, Bruce Farquhar wrote:
...

Agreed, all I'm saying is they do go wrong.

But _NO_ commercial reactors have "exploded" from the fuel having had an
uncontrolled chain reaction.

Chernobyl was so destructive because the Russky's didn't build a
containment structure to save $$ and so the fire melted the housing
structure (essentially just a "Butler building") and thus let the smoke
plume disperse the gaseous and light fission products. But, it was a
conventional fire, not a nuclear explosion that was the event.

Would a nuclear explosion have been a lot worse? Twice as bad? 50 million times as bad? Would it be similar to a nuclear weapon? Or is there a big difference in yield?

"Tim Streater" wrote in message
.. .
In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:22:20 -0000, Tim Streater

wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed
wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

Whatever happened to those AA nuclear batteries? I assume
they worked the same.

What on earth are you talking about?

https://en.wikipedia.org/wiki/Atomic_battery

On 12/10/2018 12:44 PM, Bruce Farquhar wrote:
On Mon, 10 Dec 2018 18:36:44 -0000, dpb wrote:

On 12/10/2018 9:42 AM, Bruce Farquhar wrote:
...

Agreed, all I'm saying is they do go wrong.

But _NO_ commercial reactors have "exploded" from the fuel having had an
uncontrolled chain reaction.

Chernobyl was so destructive because the Russky's didn't build a
containment structure to save $$ and so the fire melted the housing
structure (essentially just a "Butler building") and thus let the smoke
plume disperse the gaseous and light fission products.* But, it was a
conventional fire, not a nuclear explosion that was the event.

Would a nuclear explosion have been a lot worse?* Twice as bad?* 50
million times as bad?* Would it be similar to a nuclear weapon?* Or is
there a big difference in yield?

Of course it would have been, but it's pointless to speculate because
commercial reactor design is such that a supercritical mass required to
have a weapons-type reaction is simply physically impossible to occur.

What is the difficulty and the cause of reactor damage at TMI and
Fukushima is loss of effective core cooling and subsequent fuel cladding
failures or fuel melt. But, it's still not an uncontrolled nuclear
reaction event.

The most dangerous situation at TMI by far was making one's way thru the
crowd of reporters jamming cameras and microphones in your face on the
way to/from the gate at shift change...

--

On Mon, 10 Dec 2018 18:48:55 -0000, Tim J wrote:



"Tim Streater" wrote in message
.. .
In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:22:20 -0000, Tim Streater

wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed
wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?

Probably not that cheap, once you've made the Pu-238.

Whatever happened to those AA nuclear batteries? I assume
they worked the same.

What on earth are you talking about?

https://en.wikipedia.org/wiki/Atomic_battery

Not wanting to read the entire article, apart from space are we using any now?

And eeek! Pacemakers! Don't think I like that idea.

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 15:33:33 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 13:25:54 -0000, Tim Streater

wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 09:20:58 -0000, Tim Streater

wrote:

In article , Bruce Farquhar
wrote:

On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein

wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Wrong.

Are you an ostrich or something?

No, I'm just someone who, unlike you, knows his arse from a hole in the
ground.

Yet you think a nuclear station has never gone wrong.

I have never said this.

I said "We do have nuclear power stations which can and do explode...."
You said "Wrong."

Only Fukushima exploded.

but even I know many nuclear power stations have ****ed up.

Three is not "many".

You said never.

When?

Lemme see, 3 mile island

Where no one died or was injured. No external damage.

Chernobyl,

Where less than 100 died from the disaster.

So the radiation left won't hurt anyone or cause any costs or problems?
You
really are an ignorant fool.

That's a different issue.

But still very significant.

that one in Japan....

Yeah, that one in Japan - for your information that was at Fukushima.
Where no one died and no one was injured.

Tell the Japanese it wasn't a problem. Why do you think it's ok if no
injuries or deaths occur?

Because it already tells us a lot.

So if my car crashed due to a fault and didn't hurt me, that would be ok
for me to have to pay out £1000s for repairs?

What about future cancers to those nearby?

Who says there will be any?

Everyone.

Wrong again, only some ignorant fools.

Nukes in fact put far less radiation into the
atmosphere than coal fired power stations.

What about the cost of rebuilding everything?

Rebuilding what? As it happens, the Fukushima plant was due to be
closed within 6 months of the incident anyway - end of life.

And no damage was caused by the reactors. All the damage was from the
tsunami, which caused some 25,000 deaths. Perhaps you should be
concerned about that.

What about the damage to wildlife?

What damage to wildlife?

Radiation will do that.

It didn't with Chernobyl or 3 mile island or Fukushima.

And, for your information, you should look up "deaths from ordinary
industrial accidents", you'll find the numbers to be much larger.

Only if you take the numbers too literally like you do.

Why shouldn't I take them literally?

Because you're not taking into account other significant problems.

There are no other significant problems.

And if your point is to say that nuclear power stations are a good idea,
then I agree with you. But they are not completely safe.

Much, *much* safer than other forms of energy generation.

Agreed, all I'm saying is they do go wrong.

Everything does, even roads and buildings.

On Mon, 10 Dec 2018 18:52:33 -0000, dpb wrote:

On 12/10/2018 12:44 PM, Bruce Farquhar wrote:
On Mon, 10 Dec 2018 18:36:44 -0000, dpb wrote:

On 12/10/2018 9:42 AM, Bruce Farquhar wrote:
...

Agreed, all I'm saying is they do go wrong.

But _NO_ commercial reactors have "exploded" from the fuel having had an
uncontrolled chain reaction.

Chernobyl was so destructive because the Russky's didn't build a
containment structure to save $$ and so the fire melted the housing
structure (essentially just a "Butler building") and thus let the smoke
plume disperse the gaseous and light fission products. But, it was a
conventional fire, not a nuclear explosion that was the event.

Would a nuclear explosion have been a lot worse? Twice as bad? 50
million times as bad? Would it be similar to a nuclear weapon? Or is
there a big difference in yield?

Of course it would have been, but it's pointless to speculate because
commercial reactor design is such that a supercritical mass required to
have a weapons-type reaction is simply physically impossible to occur.

What is the difficulty and the cause of reactor damage at TMI and
Fukushima is loss of effective core cooling and subsequent fuel cladding
failures or fuel melt. But, it's still not an uncontrolled nuclear
reaction event.

The most dangerous situation at TMI by far was making one's way thru the
crowd of reporters jamming cameras and microphones in your face on the
way to/from the gate at shift change...

Indeed. Reporters should be outlawed, poking their noses into everything and making **** up.

In "Bruce Farquhar" writes:

Whatever happened to those AA nuclear batteries? I assume
they worked the same.

What on earth are you talking about?

https://en.wikipedia.org/wiki/Atomic_battery

Not wanting to read the entire article, apart from space are we using any now?

And eeek! Pacemakers! Don't think I like that idea.

Not to worry, ain't no more of them.

Back 1975ish there were some installed (afraid I have
no idea of the number [a]) in patients because of
the issues of standard battery life.

This was a short term program due to a bunch of
coinciding issues:

a: huge cost involved
b: standard batteries got _much_ better around then,
both in regards to power density and life span.
Oh, and leakage.
c: the Nuclear Regulatory Commission required radiation
licensing/certification of a big number of the people
involved in the process. In other words, it wasn't
like a standard pacemaker which any (competent)
medical/surgical/cardiac physician and facmility
could install and monitor.

[a] about a decade ago I had a phone conversation
with one of the major (well, there are only
two or three these days...) pacemaker manufacturing
companies. They found one of their real old timers
who remembered the deal and gave me the details
he recalled.

It's just barely, barely, possible there are a handul
still in operation. Make that a thimbleful.

It's quite likely that some were buried with their
recipient's bodies...

Oh, there was an episode of Emergency [b] where
Roy and Johnny had a patient using one.

I don't recall offhand what problems they were
concerned with.

[b] https://en.wikipedia.org/wiki/Emergency!



--
__________________________________________________ ___
Knowledge may be power, but communications is the key

[to foil spammers, my address has been double rot-13 encoded]

On Mon, 10 Dec 2018 13:25:54 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:


Are you an ostrich or something?

No, I'm just someone who, unlike you, knows his arse from a hole in the
ground.

In fact, you aren't! Definitely aren't, Dim!

but even I know many nuclear power stations have ****ed up.

Three is not "many".

There were quite a few more with dangerous accidents, troll-feeding senile
idiot!

On Mon, 10 Dec 2018 13:19:41 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:


Whatever happened to those AA nuclear batteries? I assume
they worked the same.

What on earth are you talking about?

I suppose he simply wants you to suck him off AGAIN, Dim! He has quickly
learned that you could never resist! LOL

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 03:39:31 -0000, Rod Speed
wrote:



"Bruce Farquhar" wrote in message
news
On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Those ones used on earth don't.

Funny how some have in the past.

Just one has, Fukushima.

And even you should have noticed that with an unmanned
light house or warning light on the top of a mountain etc
that it's not that easy to stop someone grabbing it and
taking it home to power their remote holiday shack etc.

Yes but what has that to do with this conversation?

That's why few have used those on earth.

Even you should have noticed that they are a tad
harder to pinch for your holiday shack when in a
space probe tearing off to look at Venus etc.

Well, since you ask:

[wiki]

In addition to spacecraft, the Soviet Union constructed
many unmanned lighthouses and navigation beacons
powered by RTGs.[5]
......
One RTG, the SNAP-19C, was lost near the top of Nanda
Devi mountain in India in 1965 when it was stored
in a rock formation near the top of the mountain
in the face of a snowstorm before it could be
installed to power a CIA remote automated station
collecting telemetry from the Chinese rocket testing facility.
=======
rest:
https://en.wikipedia.org/wiki/Radioi...tric_generator
On Sat, 08 Dec 2018 21:04:59 -0000, Brian Gaff

wrote:

I'm sure you know this but the Voyager spacecraft are using
thermocouples
using the heat from decaying plutonium for power all the way out in
the
cosmos. it may be reducing now but its been one heck of a long
time.

On Mon, 10 Dec 2018 15:33:33 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:


And if your point is to say that nuclear power stations are a good idea,
then I agree with you. But they are not completely safe.

Much, *much* safer than other forms of energy generation.

Not by any normal standards, troll-feeding retarded senile idiot!

On Mon, 10 Dec 2018 15:50:29 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:

As it has been doing since the dawn of time. You are perhaps unaware
that, every second, some 4,000 disintegrations of radioactive nuclei
take place in your body - and mine, and everyone else's. And the body
has mechanism for repairing the damage, which are at work all day every
day.

And the presence of these radioactive atoms has nothing to do with
nuclear power stations or bomb tests. Or Chernobyl.

Absolutely idiotic EVASION of the issue of the dangers of nuclear plants,
you retarded, troll-feeding, senile idiot!

On Mon, 10 Dec 2018 19:33:23 -0000, Rod Speed wrote:



"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 03:39:31 -0000, Rod Speed
wrote:



"Bruce Farquhar" wrote in message
news On Sun, 09 Dec 2018 23:28:59 -0000, danny burstein
wrote:

In "Bruce Farquhar"
writes:

Why are these not used on earth?

Do you really, really, want chunks of plutonium
or strontium 90i sitting around?

We do have nuclear power stations which can and do explode....

Those ones used on earth don't.

Funny how some have in the past.

Just one has, Fukushima.

And even you should have noticed that with an unmanned
light house or warning light on the top of a mountain etc
that it's not that easy to stop someone grabbing it and
taking it home to power their remote holiday shack etc.

Yes but what has that to do with this conversation?

That's why few have used those on earth.

Even you should have noticed that they are a tad
harder to pinch for your holiday shack when in a
space probe tearing off to look at Venus etc.

Just what size of these things are you considering people might nick, what does it power, and why wouldn't they steal an alternate power device?

Well, since you ask:

[wiki]

In addition to spacecraft, the Soviet Union constructed
many unmanned lighthouses and navigation beacons
powered by RTGs.[5]
......
One RTG, the SNAP-19C, was lost near the top of Nanda
Devi mountain in India in 1965 when it was stored
in a rock formation near the top of the mountain
in the face of a snowstorm before it could be
installed to power a CIA remote automated station
collecting telemetry from the Chinese rocket testing facility.
=======
rest:
https://en.wikipedia.org/wiki/Radioi...tric_generator
On Sat, 08 Dec 2018 21:04:59 -0000, Brian Gaff

wrote:

I'm sure you know this but the Voyager spacecraft are using
thermocouples
using the heat from decaying plutonium for power all the way out in
the
cosmos. it may be reducing now but its been one heck of a long
time.

On Mon, 10 Dec 2018 10:11:24 -0800 (PST), bob_villa, an especially retarded,
troll-feeding, senile Yankietard, babbled:

On Monday, December 10, 2018 at 10:58:04 AM UTC-6, Bruce Farquhar wrote:

Bruce, learn how to filter or ignore the JO's here. They are baiters/'baters!

Man, are YOU retard! LMAO

On Mon, 10 Dec 2018 19:09:27 +0000, Dim Streater, an especially retarded,
troll-feeding, troll-feeding senile idiot, blathered:


So you think no damage was caused? Do I really have to google it for you?

What damage was directly caused by the Fukushima Nuclear Power Station?

HAHAHAHAHAHAAA!!! Just HOW senile are you, senile idiot? Keep sucking his
cock! It's the only thing you are obviously good at! tsk

On Mon, 10 Dec 2018 19:09:27 +0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 15:50:29 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

On Mon, 10 Dec 2018 15:33:33 -0000, Tim Streater
wrote:

In article , Bruce Farquhar
wrote:

Yet you think a nuclear station has never gone wrong.

I have never said this.

I said "We do have nuclear power stations which can and do explode...."
You said "Wrong."

What was wrong was your implication that they does this often and on a
regular basis.

I said "can and do" - that doesn't mean "often".

Tell the Japanese it wasn't a problem. Why do you think it's ok if no
injuries or deaths occur?

Because it already tells us a lot.

So if my car crashed due to a fault and didn't hurt me, that would be ok for
me to have to pay out £1000s for repairs?

In the case of Fukushima, repairs to what?

So you think no damage was caused? Do I really have to google it for you?

What damage was directly caused by the Fukushima Nuclear Power Station?

What about future cancers to those nearby?

Who says there will be any?

Everyone.

You mean over and above background?

Clearly.

So who says and how many. There again, it depends what we mean by
background. Most of the evacuated zone was less radioactive than
Dartmoor.

What about the damage to wildlife?

What damage to wildlife?

Radiation will do that.

As it has been doing since the dawn of time. You are perhaps unaware
that, every second, some 4,000 disintegrations of radioactive nuclei
take place in your body - and mine, and everyone else's. And the body
has mechanism for repairing the damage, which are at work all day every
day.

And the presence of these radioactive atoms has nothing to do with
nuclear power stations or bomb tests. Or Chernobyl.

Go into the restricted zone at Chernobyl without any protection then
report back.

We could ask the people who live there.
I will have to agree with Timmie that atomic energy is as safeas, or
safer than, most other forms of electrical energy production with a
few caviats.

When something DOES go wrong, the possibilities can be extreme.
There are several different competing technologies - and the SAFEST
one by a long shot is CANDU.
Disposal of spent fuel and safe shutdown and mothballing of reactors
MAY be a significantproblem in the future.

As far as Chernobyl and Fukishama, the effects of the leaked radiation
may never be fully known - but the FACT there will be detrimental
effects is known and accepted by anyone with hal;f a functioning brain
cell.

Radiation - man made or man influenced or not - is KNOWN to have
health issues - as basic as increased skin cancer from extreme
exposure to sun-light.

Anything that increased our exposure to harmfull radiation SHOULD be
of concern, but risks and benefits need to be assessed and balanced.

On Mon, 10 Dec 2018 12:36:44 -0600, dpb, the mentally challenged,
troll-feeding, senile idiot, blathered:


Chernobyl was so destructive because the Russky's didn't build a
containment structure to save $$ and so the fire melted the housing
structure (essentially just a "Butler building") and thus let the smoke
plume disperse the gaseous and light fission products. But, it was a
conventional fire, not a nuclear explosion that was the event.

Nobody ever talked about a nuclear explosion, troll-feeding, senile idiot!
tsk

"Bruce Farquhar" wrote in message
news
On Mon, 10 Dec 2018 17:53:15 -0000, newshound
wrote:

On 10/12/2018 14:32, Bruce Farquhar wrote:
On Mon, 10 Dec 2018 11:16:54 -0000, newshound
wrote:

On 08/12/2018 22:59, Andrew Gabriel wrote:
In article ,
Clive Arthur writes:
On 08/12/2018 17:51, Bruce Farquhar wrote:
On Sat, 08 Dec 2018 17:40:57 -0000, wrote:

On 12/8/18 11:41 AM, Bruce Farquhar wrote:
On older boilers (furnaces if you're American), when the heating
isn't
actually running (eg. the thermostat says the house is warm
enough),
there's no power to the boiler, so how does the pilot light valve
stay
open with the tiny voltage (40mV?) and current from the
thermocouple?

To *hold* the valve open only requires a small voltage & current.
To
*pull* the valve open would require a larger voltage. That's why
you
have to "Press & Hold" the manual knob to restart a pilot.

See here for more detail:
https://en.wikipedia.org/wiki/Thermo...pliance_safety

I see, thanks. I thought the "press and hold" was just to keep the
valve open until the thermocouple warmed up. So I'm providing the
effort to open the valve with my thumb. That link states 0.2-0.25A
- do
you really get that much current off a thermocouple?

Yes, it's a very low impedance source, a metal to different metal
contact. 10mV 200mA is 50 milliohms. It's only 2mW, but that's a
very
small proportion of the pilot flame power.

Indeed - a pilot flame is typically around 250W.

Interesting. I thought that sounded like quite a lot. A quarter of a 1
bar fire? Half the output of a big halogen flood? Found a web site that
says a tea-light is about 50 watts (4 grams per hour), so I guess it's
probably about right.

Common sense tells us it can't be. A quarter of a 1 bar fire would make
the water in the boiler pretty warm! Now remember that at this point
the pump isn't running, so that heat can't easily move to the
radiators. The boiler would get piping hot pretty quickly. My medium
sized gas boiler is rated 4-12kW (depending on the gas pressure
setting), which would mean it's still using up to a 16th of the gas when
turned off! That would be truly absurd. The only thing as stupidly
inefficient as that is a Sky satellite TV box which uses precisely the
same 38W when in standby as when switched on!

Oh I don't know. In the dim and distant past, my boiler which had a
pilot light was floor standing and about 0.6 x 0.6 x 1 metre high.
Giving it a surface area of about 2.4 square metres. Much bigger than a
modern boiler I know, but modern boilers don't have them. So, taking a
convective heat transfer coefficient of 10 W/m^2K the surface
temperature rise to dissipate 250 watts if it does not go anywhere else
is about ten degrees C. Warm to the touch but not huge. And I bet 90% of
the energy used to go out of the flue.

In the mid 70's I had a multipoint gas water heater which, IIRC, was 22
kW. The exposed surface was probably only half that of the boiler in the
calculation, but that had a fairly lively pilot light and the casing was
always perceptibly warm to the touch.

I once calculated my gas usage for the pilot light to be £10 a month (at
3.5p a kWh) on my 12kW boiler, as it was the only thing running over the
summer. That's a ridiculous cost,

But now most gas suppliers have a fixed charge even if you don't use any gas

no wonder they use electric ignition now. Not sure why they didn't always
do that - gas cookers have had spark ignition for at least 40 years, if
not more.

But those werent automatic, they required someone to pull the trigger.

Even if they didn't have a spark that could operate millions of times, it
could always light a pilot and extinguish it if not in use for a certain
amount of time.

Some did do that with house heating only boilers.

My 'maiden aunts' used to have a gas hot water
system for their bath. Had to be manually lit.