Efficiency of utilities

"Steve Terry" wrote in message
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"TrevM" (delete) wrote in message
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"Dave Plowman (News)" wrote in message
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In article ,
TrevM (delete) wrote:
"Dave Plowman (News)" wrote in message
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In article ,
Johnny B Good wrote:
snip
But you could run the pump from a watermill or windmill. Would the
heating
then be provided by water or wind?

Now you're talking! But there are very few watermills to go around, and
the wind is too intermittent in most places...
TrevM


Sod the environmentalists, build the Seven Estuary hydroelectric Tidal
barrier,
it would produce 7 Gigawatts, 24/7
10% of the countries needs, and provide a first rate road bridge on top

a 2 Gigawatt Tidal barrier could also be build across the Mersey

Steve Terry


Indeed. They will probably both be built when the oil price looks like
staying permanently above $100 or so.

TrevM

The message
from "Dave Plowman (News)" contains these words:

In article ,
Johnny B Good wrote:
Electric heating _can_ be a lot cheaper than by gas, but you need to
invest in a heatpump based system. A heatpump can provide something like
3 to 4 KW of heating per 1KW of electrical power input. It's quite
common in The States, if the newsgroup alt.energy.homepower is anything
to go by (presumably on account of the much larger market in the related
air conditioning products).

But that isn't electric heating. The pump could equally as well be run by
gas, using some form of internal combustion engine.

What you say is true, but at a typical IC engine efficiency of around
25%, there doesn't (on the face of it)seem to be much point to such an
exercise in itself (4KW gas equivilent input for a 1KW equivilent shaft
output to a heat pump that extracts 3 KW of heat from the atmosphere to
add to that of the pump loss heat to get back to a 4KW total).

However, if you needed a total heating power of 7 KW, the gas engine
driven heatpump has the merit that you can also use that 3KW of waste
heat from the engine to add to the 4KW heat energy provided by the
heatpump. The problem with this, apart from the capital outlay on a
suitably whisper quiet gas engine, is the relative cost of the gas
energy compared to electric energy.

Whilst direct resistive conversion of electric power into heat costs
more than that provided by burning gas, I don't think the electrical
equivilent costs much more than twice that of gas (I honestly don't
know, and if the gas equivilent costs more than half the electric
equivilent, such an exercise is not going to be economic enough to
justify it).

My original point, however, was merely to remind everyone here that
electrical heating need not be as expensive as gas if heatpumps are
used. I'll leave the arguements about the capital outlay and
maintainance costs of such systems versus the more traditional gas
boiler based central heating system costs to others.

--
Regards, John.

Please remove the "ohggcyht" before replying.
The address has been munged to reject Spam-bots.

"Dave Plowman (News)" wrote in message
...
In article ,
Max Demian wrote:
"Dave Plowman (News)" wrote in message
...
In article , Johnny B
Good wrote:
Electric heating _can_ be a lot cheaper than by gas, but you need to
invest in a heatpump based system. A heatpump can provide something
like 3 to 4 KW of heating per 1KW of electrical power input. It's
quite common in The States, if the newsgroup alt.energy.homepower is
anything to go by (presumably on account of the much larger market in
the related air conditioning products).

But that isn't electric heating. The pump could equally as well be run
by gas, using some form of internal combustion engine.

It's still electric. You might as well say that a petrol car doesn't run
on petrol because you could adapt it to run it on LPG or replace the
engine with a diesel one if you wanted.

********. With a heat pump system it's not the electricity that does the
heating. Which is the main point of this discussion.

With an electric bar fire, it isn't the electricity that does the heating,
its the vibrating molecules of the bar.

--
Max Demian

In article ,
Johnny B Good wrote:
My original point, however, was merely to remind everyone here that
electrical heating need not be as expensive as gas if heatpumps are
used. I'll leave the arguements about the capital outlay and
maintainance costs of such systems versus the more traditional gas
boiler based central heating system costs to others.

You've not been paying attention, have you? Electricity is *not* the
energy provider when using a heatpump system. So to compare the cost of
that when used to power a heatpump to that of gas burned directly is
nonsense. As I said a watermill could power the pump too and could be
'free' compared to electricity.

--
*(on a baby-size shirt) "Party -- my crib -- two a.m

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:

In article ,
Johnny B Good wrote:
My original point, however, was merely to remind everyone here that
electrical heating need not be as expensive as gas if heatpumps are
used. I'll leave the arguements about the capital outlay and
maintainance costs of such systems versus the more traditional gas
boiler based central heating system costs to others.

You've not been paying attention, have you? Electricity is *not* the
energy provider when using a heatpump system. So to compare the cost of
that when used to power a heatpump to that of gas burned directly is
nonsense. As I said a watermill could power the pump too and could be
'free' compared to electricity.

I never _ever_ disputed that alternative forms of energy to drive the
heatpump could be utilised. I'm not quite sure why you're emphasizing
that "Electricity is *not* the energy provider", unless you're getting
confused over the issue of prime motive force to drive the pump and
where the calorific heat is being extracted from (in this case, the
atmosphere[1]).

[1] Ground heat source or sinks have a whole set of problems of their
own (as does using the heat energy in the air). A better bet might be a
large stream or small river that doesn't completely freeze in the
winter, but very few of us are so priviledged as to have legal access to
such sources of heat.

--
Regards, John.

Please remove the "ohggcyht" before replying.
The address has been munged to reject Spam-bots.

In article ,
Johnny B Good wrote:
The message
from "Dave Plowman (News)" contains these words:

In article ,
Johnny B Good wrote:
My original point, however, was merely to remind everyone here that
electrical heating need not be as expensive as gas if heatpumps are
used. I'll leave the arguements about the capital outlay and
maintainance costs of such systems versus the more traditional gas
boiler based central heating system costs to others.

You've not been paying attention, have you? Electricity is *not* the
energy provider when using a heatpump system. So to compare the cost of
that when used to power a heatpump to that of gas burned directly is
nonsense. As I said a watermill could power the pump too and could be
'free' compared to electricity.

I never _ever_ disputed that alternative forms of energy to drive the
heatpump could be utilised. I'm not quite sure why you're emphasizing
that "Electricity is *not* the energy provider", unless you're getting
confused over the issue of prime motive force to drive the pump and
where the calorific heat is being extracted from (in this case, the
atmosphere[1]).

I'm not confused - you are by saying 'electrical heating need not be more
expensive than gas'. It's simply too open to confusion - the sort of thing
a government spokesman says who has no understanding of the subject and
wants a soundbite for the public.

If you made it 'alternatives are available to burning energy direct to
heat your house' or somesuch there would be no argument from me.

[1] Ground heat source or sinks have a whole set of problems of their
own (as does using the heat energy in the air). A better bet might be a
large stream or small river that doesn't completely freeze in the
winter, but very few of us are so priviledged as to have legal access to
such sources of heat.

--
*We waste time, so you don't have to *

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 18 Nov 2008 15:20:09 -0000, "Steve Terry"
wrote:

"TrevM" (delete) wrote in message
.. .
"Dave Plowman (News)" wrote in message
...
In article ,
TrevM (delete) wrote:
"Dave Plowman (News)" wrote in message
...
In article ,
Johnny B Good wrote:
snip
But you could run the pump from a watermill or windmill. Would the
heating
then be provided by water or wind?

Now you're talking! But there are very few watermills to go around, and
the wind is too intermittent in most places...

everyone seems to forget the UK includes Scotland where there is a
fair bit of hydroelectric generation.

TrevM

wind would be great if it works on a large scale, but once we get to
where fans become a big part of the generation mix, the UK may have
problems keeping the electricity system stable.

the initial estimates for a wind farm near here seem to be that over a
year it will generate 15% average of notional full load per turbine.

Denmark is already proving that once you get to large percentage of
wind power in the generation mix you struggle to use the power
effectively
their grid seems to stay balanced by importing / exporting power to
their neighbours.
Which is fine until big chunks of Europe try to do it when all the
fans spin at the same time.


Sod the environmentalists, build the Seven Estuary hydroelectric Tidal
barrier,
it would produce 7 Gigawatts, 24/7

Er no - tidal power remember.
roughly twice a day you get no difference in level on each side of the
dam, so no pressure to drive the generator.
http://www.oceanenergycouncil.com/in...al-Energy.html

or at least that is what happens at the only one i know of that works
on a large scale in France.

the main thing is that the power flow is predictable, and another pump
stoage scheme or 2 like Dinorwic could level out the flows to some
extent - but another high capital cost system, with long payback times
in decades.
http://en.wikipedia.org/wiki/Dinorwig_Power_Station

Or we exploit the fact it will be predictable and go back to "white
meters" and off peak cheap power into industries that can use it and
electric storage heaters?

10% of the countries needs, and provide a first rate road bridge on top

Yes - seems crazy that "saving the marshes" for a few birds is killing
the project when at the same time the RSPB et al are complaining that
global warming is altering bird migration patterns for UK and cutting
into bird populations.

a 2 Gigawatt Tidal barrier could also be build across the Mersey

last i heard Morecombe Bay was another good candidate. Bascially you
need a big hole in the coast, good place to put a dam and large tidal
range. And lots of money.......

Steve Terry

--
Regards

- replace xyz with ntl

"Stephen" wrote in message
...
On Tue, 18 Nov 2008 15:20:09 -0000, "Steve Terry"
wrote:

"TrevM" (delete) wrote in message
. ..
"Dave Plowman (News)" wrote in message
...
In article ,
TrevM (delete) wrote:
"Dave Plowman (News)" wrote in message
...
In article ,
Johnny B Good wrote:
snip
But you could run the pump from a watermill or windmill. Would the
heating
then be provided by water or wind?

Now you're talking! But there are very few watermills to go around,
and
the wind is too intermittent in most places...

everyone seems to forget the UK includes Scotland where there is a
fair bit of hydroelectric generation.

TrevM

wind would be great if it works on a large scale, but once we get to
where fans become a big part of the generation mix, the UK may have
problems keeping the electricity system stable.

the initial estimates for a wind farm near here seem to be that over a
year it will generate 15% average of notional full load per turbine.

Denmark is already proving that once you get to large percentage of
wind power in the generation mix you struggle to use the power
effectively
their grid seems to stay balanced by importing / exporting power to
their neighbours.
Which is fine until big chunks of Europe try to do it when all the
fans spin at the same time.


Sod the environmentalists, build the Seven Estuary hydroelectric Tidal
barrier,
it would produce 7 Gigawatts, 24/7

Er no - tidal power remember.
roughly twice a day you get no difference in level on each side of the
dam, so no pressure to drive the generator.
http://www.oceanenergycouncil.com/in...al-Energy.html

or at least that is what happens at the only one i know of that works
on a large scale in France.

the main thing is that the power flow is predictable, and another pump
stoage scheme or 2 like Dinorwic could level out the flows to some
extent - but another high capital cost system, with long payback times
in decades.
http://en.wikipedia.org/wiki/Dinorwig_Power_Station

Or we exploit the fact it will be predictable and go back to "white
meters" and off peak cheap power into industries that can use it and
electric storage heaters?

10% of the countries needs, and provide a first rate road bridge on
top

Yes - seems crazy that "saving the marshes" for a few birds is killing
the project when at the same time the RSPB et al are complaining that
global warming is altering bird migration patterns for UK and cutting
into bird populations.

a 2 Gigawatt Tidal barrier could also be build across the Mersey

last i heard Morecombe Bay was another good candidate. Bascially you
need a big hole in the coast, good place to put a dam and large tidal
range. And lots of money.......

Steve Terry

--
Regards

- replace xyz with ntl



I was involved with the radio system at Dinorwic and I can remember some
numbers.

It was supposed to cost £44m - it actually cost £484m

It was estimated that it's average running time for load balancing to
permit gas turbine and/or nuclear to come on line would be about 15
minutes. On this basis it would take around 20 years to recoup the
initial cost.

It can go from 0 to 1320MW in under 10 seconds, and if the header tank
is full it would run for a maximum of about 90 minutes. It would take
about 2.5 hours and soak up over 1600MW to pump the water back up, both
at full bore.

In fact it was found to be so efficient that they let it take to whole
load and run typically for about an hour or so, and it paid for itself
in (IMSMC) 34 months (or was it 14 months?)

If in the area it is well worth a visit.


--
Woody

harrogate three at ntlworld dot com

On Thu, 20 Nov 2008 19:31:06 +0000, Woody wrote:
It can go from 0 to 1320MW in under 10 seconds, and if the header tank
is full it would run for a maximum of about 90 minutes. It would take
about 2.5 hours and soak up over 1600MW to pump the water back up,
both at full bore.

As we all understand what is happening is that during off peak,
electricity is being used to move water to a higher elevation
and then when needed convert that stored potential energy to
kinetic energy which then drives the turbines to generate electric
power.

So, here's the stoopid, dumb question --

Is water the best fluid to drive turbines?

A more dense liquid eg mercury, be a greater store of potential energy,
but would it produce an equivalent relatively greater generation of
electricity?

With mercury there would not be the worry about water corrosion, but
there would obviously be the concern about the system being fully air
tight to prevent escape of vapors.

And are there more efficient means of storing energy that pumping water
up hill? Cheap electricity - generate hydrogen - use in fuel cell?

For instantaneous power generation perhaps not?

On Thu, 20 Nov 2008 22:34:02 +0100, J G Miller
wrote:

On Thu, 20 Nov 2008 19:31:06 +0000, Woody wrote:
It can go from 0 to 1320MW in under 10 seconds, and if the header tank
is full it would run for a maximum of about 90 minutes. It would take
about 2.5 hours and soak up over 1600MW to pump the water back up,
both at full bore.

As we all understand what is happening is that during off peak,
electricity is being used to move water to a higher elevation
and then when needed convert that stored potential energy to
kinetic energy which then drives the turbines to generate electric
power.

So, here's the stoopid, dumb question --

Is water the best fluid to drive turbines?

A more dense liquid eg mercury, be a greater store of potential energy,
but would it produce an equivalent relatively greater generation of
electricity?

With mercury there would not be the worry about water corrosion, but
there would obviously be the concern about the system being fully air
tight to prevent escape of vapors.


A reservoir full of mercury? What have you been drinking this evening?