Criticism of the current electricity market, inconsistency and prospective for renewable energies

[SebastianL]

Honestly, does coming out of formulas with contested elements advance the debate?

Couldn't you focus on elements that have a consensus instead (if there are any and it becomes clearer)

And this to focus more simply on the simplified process, as you see it...
And see if other avenues are possible?
The stumbling blocks that can be admitted/settled "apart, honestly"

Because if there are impossibilities, we should not hesitate to go on other hypotheses?

Precisely I resumed the hypotheses, a little probable that it is indeed possible to gain 3% of yield by increasing the temperature to 500°C.
This resulted in a storage yield of 53%
Here the proposal is to make the storage work from 1000°c to 500°c and to make a heat pump with this work, to increase the yield.

Now I would like to find a nice geothermal power plant at 200°c with precise technical data on the actual yield, to see what is possible in terms of storage yield

[Obamot]

Ah ok, I must say that because of my shortcomings, I was a little lost in it

A country which invests massively in geothermal energy is one of our neighbours, Switzerland. they make a precise underground mapping of all their territory, with seismic probes every 50 meters! ⁰_O

As for once the 'policy' (of security of energy supply) is on the 'right' side (getting out of dependence on fossil fuels) I'm sure you could find the information you are looking to communicate to us there .

[SebastianL]

Thanks for the lead. After it's not easy to follow as a thread, the theoretical maximum (the perfect heat pump) seems to be found.
1000°c is already 5bar of zinc pressure in the heat pipe, and making a trigger even with a fixed vane with a concentric stage to take advantage of the centrifugal force is already a huge challenge in itself. The high pressure enters in the centre, exits via a radial snail with the hot water and steam inlets on the upper and lower edges.
Finally the principle of this pump is a bit like a gas fridge, with the heat we accelerate a gas, which brings with it a refrigerant.
The liquid water pump, work from 70bar to 1000bar, the work (net loss) will not be monstrous but will have to withstand 285°c.

[SebastianL]

Also, to keep the possibility of making a better production peak and a rapid discharge of the HT storage, it suffices to replace the hot water at 280°c with colder water with a booster at 70bar, the yield gradually falls towards 53% but increases the peak.
We can keep a certain flexibility, relative

[NCSH]

Since there are 3 engineers there who are familiar with the world of steam turbines, where is the development of ultrasupercitic technologies that would make it possible to reach the 50% threshold?

Until then, it is a question of 200 bars and 600/620°C, but beyond 220 bars and 374°C, we enter the field of so-called "supercritical" steam.

I thought I understood that there was a power limit: you can't exceed 1.20m in diameter for the two supercritical stages at 400 bars of the HP turbine.

This has led the few manufacturers in this niche to shift their attention to another supercritical fluid, CO₂ (some will still say him, what an obsession...) which makes it possible to reduce the dimensions of the turbine, or to increase the power at equal pressure.
However, we will have to wait a long time, for the moment General Electric is testing a 10 MWe, with projects in three directions.

High-temperature nuclear reactors, which will renew the genre, helium being available in limited quantities,
thermodynamic solar power plants (storage by silica or alumina particles), for night electricity,
but also to gases (implied non-fossil, hydrogen or methane), intended not for basic production but to support intermittent renewables, ie "balancing power" or "load balancing"...

It could even be (I haven't read any hint on this subject yet) that some dream of combined cycles teasing 70 or even 75% thermodynamic efficiency!

Although many commentators have already decreed the end of the Thermo-Industrial Civilization and are working to nail coffins to it, it could be that high-efficiency thermal machines will continue to play an indispensable role in the XNUMXst century, even if this is no longer as pervasive and systematic as in the XNUMXth and XNUMXth centuries.

[sicetaitsimple]

where is the development of ultrasupercites which would make it possible to reach the 50% threshold?
Until then, it is a question of 200 bars and 600/620°C, but beyond 220 bars and 374°C, we enter the field of so-called "supercritical" steam.

Not sure I have the latest info, but at least in Europe I think it's stalled. The latest demo project. financed by the EU, aiming to validate temperature conditions of 700°C (and 350bar of memory), necessary to reach 50%, stopped quite lamentably for lack of fighters a few years ago in the face of technical difficulties.
On the other hand, you make a mistake concerning the supercritical conditions. They have been achieved in all "modern" steam generators for more than 15 years, with pressures of the order of 250 to 300bar. The 600/620°c correspond to the overheating and re-overheating temperatures in the most efficient.

PS: all the more funny to see Sebastien tell us about components working at 1000bar 1000°C.
I think that the notion of creep must be unknown to him....

[SebastianL]

Co2 is very interesting to solve the problem of oxidation and take advantage of its high density, but the cold source must be under the critical pressure of co2, less than 30°c...

To resolve the creep, a phone call to Elon Musk is essential

[SebastianL]

Creep is generally divided into three phases: 
- Primary creep starts at high speed and slows down over time;
- Secondary creep has a relatively stable speed;
- Tertiary creep has a high creep rate and ends when the material breaks or ruptures

If creep recovery is measured, the test will determine stress relaxation - the rate of decrease in strain that occurs when the load is removed. Creep is sometimes called stress relaxation test


The delicate zone is 1000°c 1000bar at 600°c
the temperature ratio 873/1273=0.686 so at 686bar we are already under 600°c. The fixed fins are massive at the start because the velocity is low, with the sole objective of increasing this velocity.
Liquid water injected at 1000bar can cool each of these stationary fins.
During this acceleration phase, it must even be possible to use the Laval nozzle.

[sicetaitsimple]

If creep recovery is measured, the test will determine stress relaxation - the rate of decrease in strain that occurs when the load is removed. Creep is sometimes called stress relaxation test
The delicate zone is 1000°c 1000bar at 600°c
the temperature ratio 873/1273=0.686 so at 686bar we are already under 600°c. The fixed fins are massive at the start because the velocity is low, with the sole objective of increasing this velocity.
Liquid water injected at 1000bar can cool each of these stationary fins

You are right!
Uh, you also have the "humor" thread to exercise your talents! Not sure it will make everyone laugh, but at least it will amuse me.
Besides, the "To resolve the creep, a phone call to Elon Musk is essential was absolutely hilarious!

[SebastianL]

If creep recovery is measured, the test will determine stress relaxation - the rate of decrease in strain that occurs when the load is removed. Creep is sometimes called stress relaxation test
The delicate zone is 1000°c 1000bar at 600°c
the temperature ratio 873/1273=0.686 so at 686bar we are already under 600°c. The fixed fins are massive at the start because the velocity is low, with the sole objective of increasing this velocity.
Liquid water injected at 1000bar can cool each of these stationary fins

You are right!
Uh, you also have the "humor" thread to exercise your talents! Not sure it will make everyone laugh, but at least it will amuse me.

I want to laugh at myself, but I would prefer to have an indication of my "error" so funny, that I also take advantage of my stupidity!
Come on one last, to make you smile: we have the temperature, the velocity required in the Laval nozzle to inject oxygen and hydrogen