2013/11/27

French Nuclear Plants Have Problems

French electricity imports rise as cold spell dampens nuclear outputLondon (Platts)--26Nov2013/811 am EST/1311 GMT French net power imports slumped early Tuesday after EDF suffered an unplanned outage at its 900 MW Fessenheim 2 nuclear power reactor and demand rose on colder weather, the latest data from grid operator RTE showed.

The Fessenheim 2 reactor was taken off the grid at 04:00 local time Tuesday (0300 GMT), and no restart date was given.

The outage follows capacity limitations at several other EDF reactors, including the 900 MW Chinon 1 and Gravelines 2 reactors.

Lower temperatures increased French power demand by 2.3 GW on the day to 75.0 GW at 08:45 Tuesday and national power imports climbed from 500 MW Monday to almost 3 GW Tuesday


 
 
2013-12-14 And still the French purchase our power:

And its not just during peak demand. There seems to be something amiss with the French grid. The interconnector power must be more expensive then home grown electricity. So why do they not bring their reserves on line??
Back to normal?


The Interconnector is now fixed and UK is again buying 2GW from the French!


The wind generation is now at least 6GW (windy!) and possibly as high as 9GW (some generation is not recorded on grid (used locally)

http://www.gridwatch.templar.co.uk/

So UK was supplying up to 2GW to the French power grid. Another example of a complex system working.
However it is surprising that the French do not increase the output of their cheap(???) nuclear stations instead of buying from the UK. Perhaps they are having real problems with their system?

2013/10/30

The UK Storm of 28th October and the National Grid

The storm of 2013-10-28 managed to isolate a UK nuclear station from the National Grid leading to headlines such as:

Dungeness nuclear power station shuts down following hurricane-strength winds

St Jude’s UK storm forces the Dungeness B reactor in Kent to shut down for up to a week

The isolation from the grid means that essential systems controlling the reactor only have diesel generator backup and so for safety the reactor is shut down.
 
Just How is the loss of 1GW handled by the grid - the two plots that follow use data generated every 5 minutes (the dotted curves use the scale on the right of the plots all vertical scales are in MW):
 
 
 
Note that the bulk of the transient is compensated by pumped storage during the 1st 5 minutes (actually responds within 12 seconds) Hydro and coal and gas (CCGT) are also ramped up and pumped storage is reduced.  However at this time in the morning demand is rapidly increasing and coal and gas output cannot provide further rapid increase an so pumped supply is again increased,
 


 The plot shows data at 5 minute intervals so the immediacy of the Pumped storage is not visible.
 
 
It is also worth noting that the rarely used OCGT (inefficient gas) is brought online in case it is needed (only 50MW is utilised - past OCGT has provided up to 400MW).
 
So this aging reactor of approximately 1GW switching off is handled adequately by the system. In particular the instant response pumped storage.
 
The proposed Nuclear plant at Hinkley Point C will use 2 * 1.6GW reactors Losing one of these will equire spinning reserve (as provided by pumped storage and spinning turbines of other thermal stations)
 
Pumped storage:
 Each of Dinorwig's six generating units can produce 288MW of electricity, offering a combined station output of 1728MW.
Ffestiniog's four 90MW units have a combined generating capacity of 360MW.
 
I.e. a total of around 2GW. This will handle one of Hinkley's reactors but not both.
 

2013/09/26

Why has the UHI effect stopped for 15+ years?

The Urban Heat Island (UHI) effect.
According to Guru Watts the UHI accounts for a large part of the temperature increase seen since the 1970s ...
Using WUWT as a resource of facts!

(update 2013/10/22 - To find the posts just do a search on watts site.)

Climate Craziness of the week – with the physical signature of UHI staring them right in the face, Mann & Borenstein go with their ‘gut’ instincts

2013/08/18

Factors affecting DLWIR - NREL data (re-analysis)

Data from NREL re-analysed - spread sheet corrected, ULWIR nulling removed as this is basically the same as temperature, latest data added.

Data is dependent on cloud cover. Unfortunately cloud data is only available during daylight. Hours of darkness therefore are not included in this analysis



 The first plot shows the variation with date  (2004 to 2013) Unfortunately the calibration of the pyrgeometer (including device swapping on every calibration) shows up as a signal greater than any trend. The calibration dates are shown as dotted blue lines.

2004 - 2006 31192F3 large error
2006 - 2008 31194F3 10 w/sqm drop
2008 - 2009 31192F3 random 8w/sqm p-p
2009 - 2011 31194F3 10 w/sqm drop
2011 - 2012 31192F3 random 13w/sqm p-p
2012 - 2013 31194F3 random 10w/sqm p-p
It appears that 31194F3 has a drift with time (now possibly corrected)
Also it seems that +-5w/sqm is the expected accuracy for this type of pyrgeometer



Luckily this is the only data extraction that is synchronous with date. Other extraction will tend to remove the drift by averaging. It is significant that the calibration adjustments show up indicating that this spreadsheet successfully sees valid changes of <5w class="goog-spellcheck-word" span="" style="background: none repeat scroll 0% 0% yellow;">sqm

This next plot shows the expected variation of dlwir with temperature.

It should be noted that the drop in value at the high temperature end is most likely due to the small number of results returned and is therefore not valid.

The net plot shows the effect of increasing absolute humidity

The following pair show the change with day of the year. Note that temperature effects should have been nulled so the peak should not be due to summer temperature. The second plot compares La Jolla CO2 with the dwlir. The dwlir seems to show the inverse of what would be expected!




Station pressure below, has very little effect on dwlir


Opaque cloud cover increases the dwlir!



Data from:
http://www.nrel.gov/midc/srrl_bms/










2013/07/08

Temperature dependence - more analysis of NREL data

This analysis shows the interdependence of temperature and other data.
Temperature may be the cause or the effect!
The second curve on each plot shows the number of results returned. Obviously the more results the more likely the data returned is valid.
All data is averaged with the top and bottom 30% discarded to remove outliers



Temperature is affected negatively by the absolute humidity (gms h2o/cu m). To heat air and water vapour takes more energy than air alone hence the negative slope.


Using the nulling technique produces a plot with little day of year dependence (no annual peak or dip is obvious).
The slope of the line is =0.0001602 per day. This equates to 0.585°C per decade and this is over a period that people say the warming has stopped!


As expected with opaque cloud cover the temperature is negatively correlated.


Temperature with day of year is as expected with a peak at day 200 (19th July) and a minimum at day 40 (9th February). These dates are of course offset from longest/shortest day.

Plots of the nulled variables:


Note that the nulled portion is sometimes limited to less than whole range. In this case a limit is used to only accept data for that nulled range on that variable

Also the nulling process is only used to produce a line of zero slope for each variable - the offset from zero is not relevant as only anomalies are plotted.

Data from:
http://www.nrel.gov/midc/srrl_bms/







2013/06/28

Bird Deaths by Wind Turbines

Since I've been banned from commenting on WUWT here is my response to
http://wattsupwiththat.com/2013/06/28/imagine-the-outrage-from-environmentalists-if-it-had-been-an-oil-derrick/

All bird deaths obviously should be avoided but consider your personal footprint in these deaths:

From Forbes

http://www.forbes.com/sites/kellyphillipserb/2013/05/04/scientist-pitches-proposal-to-curb-bird-deaths-a-tax-on-cats/

Berthold referred to a study published earlier this year in Nature Communications which found that free-ranging domestic cats kill 1.4–3.7 billion birds (as well as 6.9–20.7 billion mammals) annually: that works out to 40 birds killed per cat every year. Many of those birds represented the end of their species: as many as 33 species of birds are thought to have been eradicated by cats. However, it’s worth noting that stray cats, as opposed to pets, cause most of the damage.

 From Sibley Guides

Figures are believed to be US only

http://www.sibleyguides.com/conservation/causes-of-bird-mortality/
Window strikes – estimated to kill 97 to 976 million birds/year

Here's one that didn't make it. Window on our house facing west.

Communication towers – estimates of bird kills are impossible to make because of the lack of data, but totals could easily be over 5 million birds/year, and possibly as many as 50 million.
Electrocutions kill tens of thousands of birds per year. This occurs mainly when large birds such as raptors make contact between a live electrical wire and a ground such as a pole. The relatively small number of birds affected belies the significance of this threat, since species such as Golden Eagle are more susceptible.
Cars may kill 60 million birds per year.
Wind turbines may kill 33,000 birds per year, and, as in the case of electrocutions, these birds tend to be large and scarce (e.g. raptors)
Pesticides may kill 72 million birds per year or possibly many more.
Oil spills kill hundreds of thousands of birds a year or more
Oil and wastewater pits may kill up to 2 million birds per year.
Lead poisoning – kills unknown numbers of birds each year, but Bellrose (many years ago) estimated that about 4% of the waterfowl population dies annually due to lead poisoning, and the California Condor recovery team stated that lead poisoning was the primary cause of the condor population decline over the last 50 years
Hunting - as a point of reference the carefully-managed annual waterfowl hunt kills about 15 million birds a year in North America. This, of course, is balanced by extensive and well-funded management and conservation efforts so hunting is not a threat to the population of any North American bird,
Domestic and Feral Cats – may kill 500 million birds per year or more. 

From a famous twitcher





2013/06/19

Energy costs

UK fuel costs

Note electricity prices well behind raw fuel costs.
 
 GERMAN electricity price at auction


Note pronounced dip in price during peak solar output

FRENCH electricity price


Note no real solar dip and cost is greater than Gemany despite being nearly all nuclear

2013-06-23
Interesting UK Grid and wind:


Wind is currently producing the same energy as coal. Also note the depressed peaks in daily use as wind begins to generate (however it is olso necessary to allow for the fact the wind increased at the weekend=low use).
Note also the grid safely handled an increase from about 500MW to 5GW without incident
The graphics are from the site
http://www.gridwatch.templar.co.uk/



2013/06/08

More Fun With a Thermal Imaging Camera

How does hot air at 450°C show up on a thermal imaging camera:

It doesn't until you allow it to hit an object (in this case paper)
 See video here:
http://youtu.be/AsmrA_u0Ud0


Comparison of Atmospheric Transmission Germanium Lens response and quoted FLIR camera response
Note that the camera response is in a highly transmissive part of the atmospheric transmissive window - to put the passband in a place where the GHGs radiate would give continual fogging due to the air between object and camera rather than the object desired.


How good is bubble wrap (packing material with 0.5cm air bubbles trapped between plastic)



Single and double layers over hand. The spot temperature has had the emissivity adjusted so don't believe the temperature!
See video here
http://youtu.be/xE08j2jKItI


Using the software's ability to calculate emissivity from the displayed temperature and the known hand temperature (approx 37°C with emissivity 0.92) gives the following results:
1 layer of bubblewrap requires an emissivity of 0.70 to correct the hand temperature to 37°C
2 layers of bubblewrap requires an emissivity of 0.69 to correct the hand temperature to 37°C 
4 layers of bubblewrap requires an emissivity of 0.58 to correct the hand temperature to 37°C
8 layers of bubblewrap requires an emissivity of 0.55 to correct the hand temperature to 37°C

Compare this to 2 layers of cling film (saran wrap/ldpe) here
http://climateandstuff.blogspot.co.uk/2013/03/does-thermal-radiation-travel-from-cool.html

2 layers of ldpe are equivalent to 4 layers of bubble wrap (8layers of plastic and some air)

So an IR window of 2 layers bubble wrap  (bubbles interspersed) will be better at IR transmission and probably better at conduction prevention.

You need aluminised bubble wrap to prevent hypothermia - need to stop the loss of IR!!!!




2013/06/02

The (Copper) Iron Green House Revisited

Other posts on this subject
http://wattsupwiththat.com/2009/11/17/the-steel-greenhouse/
http://climateandstuff.blogspot.co.uk/2013/04/the-copper-greenhouse-new-test.html
http://climateandstuff.blogspot.co.uk/2013/03/the-copper-greenhouse.html
http://climateandstuff.blogspot.co.uk/2013/03/a-cool-object-reduces-energy-loss-from.html
http://climateandstuff.blogspot.co.uk/2013/03/does-thermal-radiation-travel-from-cool.html
http://climateandstuff.blogspot.co.uk/2012/05/cool-body-can-transfer-measurable-heat.html

The iron greenhouse energy budget

 
The tests trying to produce some replication of Willis's Iron greenhouse have been repeated using a multichannel thermocouple probe recorder measuring to 0.01°C (accuracy 1°C) and somewhat modified test setup.

The sensor has been modified to make it more responsive (less copper in the plate than in the original cone. Fine wire thermocouple used to reduce the heat conduction.




 The insulated hot box uses much thicker insulation and the double sided grey sprayed copper plate temperature is monitored using another fine wire thermocouple. The temperature between the 2 IR windows and outside the window is now measured. A small fan is used to provide a continuous stream of ambient air between the hot box and the sensor to prevent conduction and convection effects upsetting the sensor reading. The heating voltage is maintained to 9.254 volts +-3mV ensuring constant power input to the hot body.



The object of the experiment is not to replicate EXACTLY the steel greenhouse thought experiment. For a starter the hot object is only "surrounded" on one side and the major loss of heat from the object is via conduction through the insulation. There is obviously conduction and convection occurring in the experiment which are prevented by using a vacuum in the thought experiment.

Inside of Hotbox

Table-top setup


Grey painted Plate Insertion:

What is expected is a significant increase in the hot body temperature when the grey plate is inserted. The Sensor should report a drop in temperature until the system has reached equilibrium It should then be at the same level as before the grey plate was inserted - I.e. the radiation from the hot box should be constant before and after grey plate insertion.

Reflective plate insertion


The rise in temperature of the hot body should now be significantly hotter than either no plate or grey plate (100% of forward facing IR should now be reflected back onto the hot body causing the temperature to rise until the additional energy balance can be restored.
The sensor should show a drop in heat for the time that the reflective plate is in position.

Method
  1. During the test the voltage applied to the resistors heating the hot body is monitored and maintained within +-3mV of the nominal (giving a power variability of 0.065%)
  2. The test setup was run monitoring  temperatures for about 10 hours. 
  3. The recorded results were then analysed over a period when the ambient was most stable (after sunset).
  4. To allow for ambient vatiation the measured forced ventilation temperature in front of the IR window was smoothed and then subtracted from the hot body temperature.

Results
The first temperature rise is with a reflective plate  and the second rise is with a grey painted copper plate inserted between hot body and IR window. The low temperatures are when no intermediate plate is inserted.
The air outside the IR window plot (green) is the temperature as measured from the forced airflow. The corrected temperatures refer to measured temperature less the air temperature.



The temperature of the Hot Body shows results as expected - maximum temperature from reflective plate lower temperature from grey plate lowest temperature from no plate.

The measured temperature (= IR output) from the sensor does not agree with expected result..

With the grey plate not equalling the hot body temperature there would be expected lower IR emission so perhaps this could explain the lower temperature compared to no plate.

With the reflective plate the IR output does not go to zero. possibly the plate warms and the insulation is insufficient. The IR sensor needs to be improved - possibly an IR thermometer? But will these then read the temperature of the IR windows?

So the results show
A definite increase in hot body temperature if a reflective plate is used  (5.5°C)
A definite increase in hot body temperature if a grey plate is used  (3.5°C)

If you believe that backradiation or reflection cannot add energy to the hot body from which the radiation originates then these results alone disprove this belief.

2013/05/28

Back Radiation Early Results - No Fan

Using the setup of the previous post
http://climateandstuff.blogspot.co.uk/2013/05/proposed-back-radiation-test-setup.html
 but with no fan and no shadow dot used the following results have been obtained.
(x-axis is in seconds from start of test - many tests were done and recorded over about 12 hours - the main problem is trying to keep ambient constant or at least clear of low frequency noise)



Detrended by the air gap temperature between double glazed and single IR window the plot shows that with Warm source in place Hot body is 0.3°C hotter than when ambient source is in place


This shows a continuous recording of the warm source temperature - the Red line indicates that the source is facing the IR windows -  the dotted lines indicate that it has been placed away from the IR windows. No attempt has been made to stabilise the warm source temperature - It simply has to be above ambient and below the hot plate temperature.


This plot shows the detrended temperature of the air between the double glazed IR window


This plot shows the air between the double glazed window and the isolated IR window. Note that it shows no sign of being warmed by the warm source. The trend is because of ambient changes. This trend was removed from the "detrended"  plots

It should be noted that the radiation from the warm plate has to pass through 3 layers of poly film to reach the hot plate. In a previous post
http://climateandstuff.blogspot.co.uk/2013/03/does-thermal-radiation-travel-from-cool.html.
I showed that this food wrap (LDPE) is not 100% transparent to IR.


Again I am certain that the hot body temperature increase is caused by the IR from the warm source.

Again criticism of the experiment is welcomed!

Full recorded data is available.

other posts on this subject:
http://www.climateandstuff.blogspot.co.uk/2013/04/the-copper-greenhouse-new-test.html
http://www.climateandstuff.blogspot.co.uk/2013/03/the-copper-greenhouse.html
http://www.climateandstuff.blogspot.co.uk/2013/03/a-cool-object-reduces-energy-loss-from.html

2013/05/27

Proposed back radiation test setup - comments?



4 Thermocouples simultaneously monitored
  a. internal temperature of double glazing gap
  b. temperature in gap between external unsealed IR window. IR shield shadows the sensor from the external IR
  c. hot temperature plate (internal)
  d. warm plate (external) ambient plate temperature is not measured.

Fan blowing ambient air between the double glazing and the separate window. This is to reduce thermal conduction and convection from a different warm/cool source affecting the ambient at the outside of the double glazed window.

Angled BB absorber at back of external source (angled to prevent reflection affecting hot plate.

Lining of polished aluminium foil to prevent IR penetrating the insulation foam.

Voltage input to external warm plate heater is stable but differing ambient and convection/conduction will change its temperature - All this needs to do is provide a temperature less than the hot plate and greater than ambient - so the variation is not important.

The voltage to the hot plate heater is also controlled (by a professional Power supply) the temperature reached is approximately 70°C and the variation with external plate at ambient / warm will be less than a couple of °C. The change in the high quality resistors value will be negligible. So constant voltage equates to constant power..

Any comments before trying this set-up

2013/05/21

Nenana Ice Classic 2013 - the ice has moved 2013/05/20 14:41

Second latest time from beginning of the year
The record was set in 1964 which was a leap year. The movement happened 140.4868 days from January 1st

This year the movement occurred 139.6118 days from January 1st

Hmmm! Perhaps this all need rejigging to relate the breakup time to the vernal equinox and z-time

Anyway, here are 2 plots using AK time:
The first splits the data into 3 segments
The second assumes that there is no upturn and hence only 2 lines
Smoothing is done with Hodrick Prescott filter from http://www.web-reg.de/hp_addin.html

Breakup data from
http://www.nenanaakiceclassic.com/




Heres the modified plot with days since vernal equinox instead of start of year:

So this year now becomes the latest date for breakup! Otherwise the shape remains.

2013/04/06

Conversation with a Slayer of The Sky Dragon

First, perhaps the most relevant post

I had suggested surrounding a internally heated body with a froven - a fridge/oven giving active heating and cooling to a set temperature.
Also body and inner surface of froven are black bodies with same albedo

 The post with clarification added!:

thefordprefect says: 2013/04/04 at 11:52 AM

[JP:... If the body has a heat source then it will stay at the temperature it was at without the oven heating it from a higher temperature. If the oven is cooler than the body than it can not heat the body. Photon quanta from a cooler source do not warm up a warmer source, even if they might exist. It is not a "sudden" cessation of effect when the oven becomes cooler than the body - it is a smooth transition in the direction of q, of heating.]

This cannot be correct.

If the temperature of the froven is warmer than the body you suggest it heats the body.
If the froven is cooler than the body you suggest it has no effect.
If the body is radiating quanta from a 100°C source then the hotter froven will be radiating to the body quanta from its 100C+ walls.
 If the body is radiating quanta from a 100°C source then the cooler froven will be radiating nothing from it 100C- as if it were at absolute zero thats one heck of a sudden step.

 Do I understand correctly?

[JP: Not quite yet. If the body is warmer than the oven, then the body heats the oven. If the oven is warmer than the body, then the oven heats the body. This is a smooth transition in the direction of heating as a function of the temperature differential: -2 -1 0 1 2 etc. A smooth transition, not a sudden stop.]

thefordprefect says: Your comment is awaiting moderation. 2013/04/05 at 11:52 AM
  Seem to have problems posting so I’ll try again:
[JP: Not quite yet. If the body is warmer than the oven, then the body heats the oven. If the oven is warmer than the body, then the oven heats the body. This is a smooth transition in the direction of heating as a function of the temperature differential: -2 -1 0 1 2 etc. A smooth transition, not a sudden stop.]
===========
you have stated definitely that there is no transfer of energy from cold to hot:

“but what I do know is that they do NOT work by cold heating hot – hahaha what a stupid idea.”
“[JP Reply: Trashed because we've already answered you. q from the shell to the planet is 0. ZERO. There is no heat loss from the shell to the planet. Even if the shell is emitting on the inside, there is no heat loss to the planet. The only direction the shell can lose heat is outwards, and hence it loses the equivalent of 800 W/m2 outwards.]”
“Radiated energy does not equate to net heat transfer or even net energy transfer. The equation of heat flow for radiation, from physics, from actual physics textbooks and from actual universities and actual physics degrees, is q ~ (T2^4 – T1^4). If T2 = T1, then q = 0, and nothing heats up, even though there’s all that radiation. ”

So firstly I hope you would agree that the quanta of energy leaving a surface cannot depend on the final destination of the quanta i.e. its temperature, material and surface – it only depends on the source material and temperature.
I also believe this describes your point of view:
The final destination of the radiation determines what happens to the quanta (rejected or absorbed)

where 100C- a very very very! small bit less than 100C 100C+ a very very very! small bit more than 100C w greater than y
y greater than x
and x greater than z

oven at 101C transfers zero quanta to body at 10000C (equivalent to back radiation)
body at 10000C transfers w quanta to oven at 101C

body at 100C transfers zero quanta to oven at 101C (equivalent to back radiation)
oven at 101C transfers x quanta to body at 100C

oven at 100C- transfers zero quanta to body at 100C (equivalent to back radiation)
body at 100C transfers x quanta to oven at 101C-

oven at 100C+ transfers x+1 quanta to body at 100C
body at 100C transfers zero quanta to oven at 100C+ (equivalent to back radiation)

body at 100C transfers y quanta to oven at 99C
oven at 99C transfers zero quanta to body at 100C (equivalent to back radiation)

oven at 10000C transfers w quanta to body at 100C body at 100C transfers zero quanta to oven at 10000C (equivalent to back radiation)

at 100C- to 100C+ oven temperature the body quanta changes from outputting x to receiving x+1 quanta
.
Somehow this does not seem to be a smooth or logical transition


Warmists would say quanta emitted from an object depends only on the object and its temperature. the final destination of the radiation is immaterial (well actually the quanta knows nothing until it hits the surface)
The sum of all quanta determines the rate of loss/gain of heat

oven at 101C transfers y quanta to body at 10000C (equivalent to back radiation)
body at 10000C transfers w quanta to oven at 101C

oven at 101C transfers y quanta to body at 100C
body at 100C transfers x quanta to oven at 101C (equivalent to back radiation)

oven at 100C- transfers x-1 quanta to body at 100C (equivalent to back radiation)
body at 100C transfers x quanta to oven at 101C-

oven at 100C+ transfers x+1 quanta to body at 100C
body at 100C transfers x quanta to oven at 100C+ (equivalent to back radiation)

oven at 99C transfers z quanta to body at 100C (equivalent to back radiation)
body at 100C transfers x quanta to oven at 99C

oven at 10000C transfers w quanta to body at 100C
body at 100C transfers x quanta to oven at 10000C (equivalent to back radiation)

Consider 100C- to 100C+ oven temperature - the100C body quanta output is x and at 100C- it receives x-1 quanta and at 100C+ it receives x+1 quanta

A smooth and logical transition.
I assume that I have this wrong somehow so perhaps using x,y,z you could explain your position

[This last post did not get past moderation!]
===========================
In pictures:
Assumed output from body and shell at 0K this is zero at 10K this is 100 quanta


.

As the energy quanta increases from zero to 100 from body B with the temperature of B increasing from 0 to 10K
 the energy quanta from shell A goes from 100 to zero as the temperature decreases from 10 to 0K

The temperature determines the quanta of energy released from the bodies

The warmist view would be that all energy from A gets absorbed by B and all energy from B gets absorbed by A irrespective of the temperature of each body

The Slayer version suggests that if the temperature of A is less than B then the transfer to B becomes zero/is reflected/cancels /nulled
and if the temperature of B is less than A then the transfer to A becomes zero/is reflected/cancels/nulled

This is shown in this diagram.

If one then looks at the net flow of quanta from A to B then the slayer version has a discontinuity where the temperatures are the same. The warmist version is a simple straight line which at B=A temperature the net transfer is zero.
===========================================

=========================================================================
The whole thread



2013/04/02

The Copper Greenhouse - new test

A rerun with improved sensor and reflective plate.

1. A grey plate should give "back radiation" and equal radiation outwards
2. A reflective plate should reflect all radiation back to heater and emit zero outwards
3. No plate should pass all radiation outwards.


Case 1. is the equivalent of the steel greenhouse of Willis Eschenbach and should cause the heater to run hotter and the emitted radiation to be the same as if the plate was not there.

Case 2. simply reflects all radiation back to the heater which should then heat up to a temperature limited by losses from conduction through the box

Case 3. Radiation from the plate facing the IR window should pass through unhindered. The heater temperature will be controlled by conduction losses and radiation losses through the window.

The experiment cannot be expected to exactly simulate the Iron Greenhouse. It should be able to show radiation through the window roughly constant between case 1 and case 2 but temperature of the heater being higher in 1. It should also show the heater reaching a higher temperature in case 2 than case 1.

The new better insulated sensor:
Additional IR window. Improved all round insulation.

The Heat Box



The results:



Note that only one temperature probe could be measured a  time thus giving the gaps in the records.
1. The grey plate allows the heater to warm to a temperature above the no plate temperature (76.8°C compared to 74.9°C)
2. the grey plate and no plate emitted energy warms the SENSOR to similar temperatures i.e. 25.5 compared to 25.6°C i.e. the emitted energy through the window is similar.
3. The reflective plate allows the heater to warm to the highest temperature with low emission of energy (sensor warmed from a background of 22°C to 23.9°C

This again shows what was expected by the existence of back radiation allowing the heater to reach a higher temperature.

Other posts on this subject
http://wattsupwiththat.com/2009/11/17/the-steel-greenhouse/
http://climateandstuff.blogspot.co.uk/2013/03/the-copper-greenhouse.html
http://climateandstuff.blogspot.co.uk/2013/03/a-cool-object-reduces-energy-loss-from.html
http://climateandstuff.blogspot.co.uk/2013/03/does-thermal-radiation-travel-from-cool.html
http://climateandstuff.blogspot.co.uk/2012/05/cool-body-can-transfer-measurable-heat.html