http://www.wrh.noaa.gov/vef/deathvalley/
I sent this last Tuesday, I have not seen a response from either individual listed here as press contacts at the press release for the 100th anniversary of the hottest temperature ever. Perhaps the questions are just too difficult. – Anthony
From: Anthony Watts
Sent: Tuesday, July 02, 2013 8:10 AM
To: daniel.berc@noaa.gov
Cc: cheryl_chipman@nps.gov
Subject: Death Valley 134 Celebration
Good morning,
I’ll be covering this event. I have some important questions that I’d like to ask.
1. Do you have press passes available?
2. Why did NOAA decommission the MMTS electronic sensor near the front of the Visitor Center last year and go back to using the mercury thermometer in the Stevenson Screen? What was the impetus? Am I correct in noting that the MMTS thermometer was in use for over a decade prior to last year?
3. When was the last time the Stevenson Screen received maintenance for paint? When I was last there, the screen looked quite chipped/peeling and had some darkened wood from aging. Is it painted with latex paint or the traditional lime based whitewash paint which was the standard in 1913 for all USWB Stevenson Screens?
4. Why does the NPS maintain the electronic sign that shows erroneous readings, such as what was highlighted in an LA Times story during the recent temperature spike?
http://www.latimes.com/local/lanow/la-me-ln-heat-wave-death-valley-hits-128-degrees-or-is-it-129-20130630,0,6477803.story
It appears the reading comes from the non-official weather station mounted at just above roof level near the front wall of the visitor center. Is that the source?
5. Who is responsible for the weather station at Badwater basin near the turn-off/parking area and where is the data from it collected? Is the data available? In your press release you indicate that the 1913 Greenland Ranch reading is “…the highest reliably recorded air temperature on Earth. “. If Badwater basin station were to exceed the 1913 reading, would it be considered reliably recorded? It seems to be near state of the art equipment.
6. How often is the mercury thermometer in the Stevenson Screen at NPS Visitor Center checked for calibration? From the photo recently posted by NPS showing the 128F reading, it appears to be well aged. What is the age of that thermometer? Has it ever been tested by NIST or similar entity?
7. Is there any sort of backup or reference thermometer in place inside the Stevenson Screen?
8. Do you have a location (lat/lon) for the 1913 location of the station in Greenland Ranch? What date was the Greenland Ranch station decommissioned, and were there other intermediate locations before the station resided behind the NPS visitor center?
Thank you for your consideration. I look forward to the event.
Anthony Watts
WUWT
lectorconstans says:
July 7, 2013 at 5:10 pm
Indeed, this is a three stage engine based on that old gardening principle.
It gains in efficiency because it can reach higher air temperatures. Just what is required in a good heat engine.
Energy storage at low speeds/high mass are at the other end to high speed ones.
Try stopping a loaded barge in the same canal with your finger. It will work but does take some time! And for a frictionless surface, a half circle floating in a sensibly larger canal and at low speed/high mass makes for a very low friction setup. If you really, really need to do so, then teflon coat the huill surface and go lower.
And provided you keep the ‘hull speed’ to about the average local wind speed then you can add ‘sails’ to to ring and do a combined solar/wind power station! A giant horizontal flow air turbine as well.
If you want it this way, this is Trevithick (old gardening setup), through Watt (super-heating) to Whittle (jet turbine) in an air engine rather than steam.
Just reaplying history to today.
A minute of latitude is one nautical mile, so you’re basically drawing us a big circle on the map rather than defining a meaningful locus.
Here’s a better guess at latitude: 36 27 40N
It’s at least in the neighborhood of the visitor’s center. I’d need more pictures to vector me in to where it really is.
Ok . so final workable design – I hope. Sorry for the Tigger bouncing up and down – Olw is back now.
—
Firstly let us describe what we are seeking (or so I believe). We are dealing with a low grade energy source (solar) which we need to collect as much of and use what we collect as well as possible. The less energy interfaces there are (such as moving to water/steam etc.) with their consequent potential losses the better. Also it must be cheap and easy to construct, locally if possible.
So the ideal engine is one that operates on air and solar input only. It should have a multi-stage layout with rising temperatures imparted to the air as we go through each stage towards the power takeoff point and have a low temperature exhaust. The pressure will remain unchanged throughout the engine. Only temperature/velocity changes as we move through it.
If you want a simple mental picture of how all this works, think “little lemon pip of air being slowly pressed between two slippery plates and getting faster all the time”.
Single Solar Air Jet Pipe.
Heat Stage 1.
Long thin box open at one end to the outside air, roofed with a black, heat absorbing/conducting panel towards the sun. Bottom and sides of insulating and heat resistent materials and sealed air tight except at the entry point.
Angled to the equinox noon sun for year round working and running West – East.
Air entering (through an air filter as required?) through the open end of the box starts heating up. It wants to expand. Because of the sealed, constant cross section of the box, it does so by moving faster on down the tube. Towards the exhaust.
Heat Stage 2.
Another long thin box constructed as above but this time with an insulating ‘glass’ roof to achieve higher temperatures in the air. Same angles to the sun. Same heating/velocity effects on the air. This is now a mechanical thermal diode series pumping power into the air as both heat and hence velocity. The pressure is still constant. Well the ‘pressure/temperature/velocity = constant’ triple point is anyway. Higher air temperatures will mean higher velocities and because this point is higher up the temperature gradient, gives a self starting capability to the engine.
On we go.
Heat stage 3.
Final box section, this time ‘on edge’ and now fully heat conductive. Cylindrical ‘mirrors’ concentrate the required power on each side. Highest air temperatures/velocity and a good top end to the input thermal gradient to get all this going fast in the morning.
Cylindrical ‘mirrors’, and hence box rather than tube, rather than parabolic for cost reasons. Can also use a very large ‘flat plane’ mirror array in extreme setups.
Now we are cooking. The air is now very hot and, because it is actually ‘pushing’ against the new outside ‘cold’ air now comming in to replace it at the entry point, it is now moving quite quickly.
Stage 1 = Trevethic. Old steam.
Stage 2 = Watt. Super-heat steam.
Stage 3 = Whittle. Jet engine.
Concentrator venturi/expander (similar to the compressor stages in the Whittle engine).
Takes the now fast, hot air from the prior ‘heat’ stages and then converts some of it’s intertial energy as required to get to an even higher local velocity in the air stream and then reverse itagain and slow it down again to get to the air temps as required by the fan/turbine input. This is probably the high point, thermally, for the engine. Downhill from here. Classic turbine entry throat.
Turbine/fan power extraction.
We now have very hot fast air, still at the ‘pressure/temperature/velocity = constant’ triple point, at the face of a turbine which is also has its exhaust at the base of a hydro-statically balanced exhaust chimney. Air flow up the chimney is driven by the temperature difference to the outside air from the turbine/fan output face up to the top of the chimney only, in the ideal case.
As the chimney/exhaust can be of any width as well as height, so final output velocities and hence temperatures can be kept as low as required to get reliable operation.
We can allow the air to expand out (and hence cool it down to the required exhaust temperature) and do work using a full, multi-stage turbine, or get somwhat less energy out by using the simple interia of larger air volumes which are required by an edge driven fan. That should get better results in that setup even though it may give higher exhaust temperatures so higher losses.
Chimney/Exhaust
The height of the chimney now is really governed only by the need to keep sufficient air flow in the exhaust stream, not to extract power as such, so the height required is correspondingly less. Just enough to reliably not choke the turbine output.
This is because we have kept to the ‘constant pressure point throughout’ requirement and kept that pinned right through even in the turbine. Even when we expand it out we are doing so at constant pressure to get the highest efficiences. Volume/temperature/velocity are what changes. Not pressure.
The overall point is that this is cheap. I mean really, really cheap. And so simple to make. If you have the odd sheet of metal and glass around you can build one in your back garden.
Do NOT allow children to get near the hot end!
Now we have a working, individual ‘solar heat air jet pipe’ then all the classical multi chamber engines then follow, in whatever scale required.
Low tech versions (which could just be single collector/concentrator stack) could be built with local materials if an edge driven fan is used instead of a turbine. Think of a lorry axle mounted vertically supporting a large horizontal fan and blades at the top. Generator takoff from where the prop shaft was. Wheel on the ground bolted to the floor.
The fan can be as large as required and made out of local materials if the heat is kept low and larger air volumes used instead. Flywheel capability can still be included (see below) to allow for night time working even at smallest scales I think.
The rest below may sound more exotic, even extreme. But I think still possibly plausible.
Ultra large scale, or storage added, versions would require a circular ‘ring’ filled with ballast, floating in a circular water canal and the ring retained by guide wheels to the bank. The top of the ring carries a set of turbine blades which interact with multiple fixed ‘heat towers’ in a similar fashion to a Whittle turbine laid out flat.
The only difference is that this engine operates at a constant pressure point and the only variables are thus velocity and temperature.
That gives an almost ‘free’ way to stored any unneeded energy that is collected. As rotational energy in a very big, slow flywheel. Big enough, who knows, to get through the Winter?
Cheap enough and efficient enough you think? Even without the storage?
Anyone want to do the maths and work out the best cost/benefit/size ratios? From Kilowatt to Gigawatt. And who builds the first prototype? Race anyone?
Fig 1.
Very basic 1.5 stage engine that started this all off.
http://i1291.photobucket.com/albums/b550/RichardLH/SolarHeatenginePowergenerator2_zps0b858de9.png
And for the second project. Should work well here if the winds are high.
Wind power for the future.
The problem with wind is the air. Its too light in mass really. In order to get useful energy collection we need to think big.
Victorian big I suspect.
And it keeps coming from all directions and so erracticaly.
So let’s start with a big flat field somewhere where the winds blow constantly enough to make this all worth while. Or a nice round hilltop which we can work with.
Draw a big circle on the ground out to the limits of the property and give it a little ‘working’ space round the outside or somewhere down from the top of the round hill.
Dig a circular canal inside the planning circle of whatever dimensions you wish. Make it a half circle in cross section.
Construct a boat ‘ring’ that is suitably smaller to give needed clearancies and float inside the canal. To fill up the whole canal area. Load with as much ballast as required to bring it down to just a half cirle below the waterline.
Place some sleepers round both inside and outside of the cannal and construct two rings of quide rails inside and outside the canal.
Add wheels to the ‘ring’ to centre it in the canal.
Add whatever friction reducing compounds you want to ‘hull’ and water.
Cover to protect against frost, evaporation, accidents, etc.
We now have a nice big, high mass, low speed, low friction bearing and flywheel to work with.
Now to get it all moving.
On the ‘ring’ add some fixed wing blades to whatever vertical dimensions local planning will allow you to get away with.
Construct them so that this is running in the low speed, high torgue end of airfoils.
Space round the ring as required to get the best overall air flow.
Remove the protective covers on the blades and wait.
Looked at from above, you now have a large vertical cross flow air turbine.
At very low cost and speed. Slowly building to the local average wind speed if you don’t take power.
Add power takoff by running some wheels off the ‘ring’ from the banks and……
Victorian really. With AC.
Will run for as long as there is wind to collect. Virtually zero maintenance and running costs.
More complicated solutions will require computer controlled airfoils or ‘faster than the wind’ propellors driving the ‘ring’ onwards.
Only for those who require the last word in efficiencies.
P.S. The above should be ‘bird friendly’ as well.
and for the full set:
Wave power for the future.
Waves are big things. Lots of mass. Really lots of energy. Difficult things and they can get VERY big.
Look at a cross section of a single wave though. It has a peak and a trough.
If we can take all of the water than is in the peak and drop it into the following trough we will have recovered all of the energy of the wave. All bar turbulence anyway.
So let’s create a mechanical diode circuit that can do just that.
Construct a large flat ‘beach’ and make it float at ‘sea level’. As wide as you can sensibly build. Point at the waves.
Add to ‘beach’, banks, in the form of an flat entry throat towards the turbines at the ‘back’.
Drop the water through the distance of the RMS average height of waves collected, half above, half below, ‘sea level’ in some large horizontal water turbines.
Take the outflow and return it to where the waves are collected as a slow ‘DC’ return to where the waves are breaking across the whole beach.
A mechanical rectifier for waves.
Build as large as required. Moor where needed.
It is also possible to add the same large ‘flywheel slow storage concept’ to this as well to create energy harvestor ships that can collect far distance waves.
Or build comunities in the oceans.