NCSH wrote:Obamot wrote:Hello and thank you very much for this sharing and this vision of the future...
I share the idea that the best efficiency will be achieved by thermodynamic solar, because it can be stored directly in the form of heat for up to 5 days (which makes it possible to solve the load factor). The 15% for the EU seems low to me with direct current lines with few losses, see superconducting lines. Thus a belt of power stations taking over one after the other would provide a continuous supply that could partially solve the load factor that is lacking in renewables.
Thermodynamic solar still has many surprises in store for us, despite a chaotic journey for more than 50 years.
In particular, a new generation of power station with tower and adjustable mirrors is being prepared, with thermodynamic efficiencies close to 50%, reached at around 700/750°C associated with heat storage for around 16/18 hours.
But it will be above all to produce power at night, within the framework of integrated complexes, as in the Noor Ouarzazate projects in Morocco, the United Arab Emirates, ... that could be the future of this type of project.
The cost of production has finally also fallen and has now reached the threshold of $100/MWhe and should fall further in future projects.
You mention the possibility of storage for 5 days. In addition to the quantities of molten salts (or better particles of silica or alumina to be able to restore temperatures of 700°C), if the Chinese and others were to deploy nuclear reactors using Thorium, there would be the problem of the resource of molten salts; but above all, 5 days is not enough to compensate for episodes of lack of wind and sun in the winter period of our so-called temperate climate.
Perhaps that would be enough for the countries of southern Europe, but in the heart of Europe it is at least 15 full days: it is now, since the beginning of 2020, a quasi-official figure mentioned in the TYNDP 2020 and 2022 reports.
This constraint of being able to massively produce electricity during prolonged winter episodes called by the Anglo-Saxons "cold spell", "dark doldrum" and by the Germans "kalt dunkelflaute" has so far been totally neglected by almost all promoters. renewable electricity in temperate countries.
This will require, to clarify this poorly known subject during the coming decade, complex and long studies combining historical meteorological data and the operation of electrical networks in rare circumstances where electricity needs in cold weather involve the intensive operation of heat pumps. for more than 50% of homes, very high proportions of individual electrified vehicles, in addition to current levels of electricity consumption.
One and only solution: the massive underground storage of natural gas or synthetic methane or even hydrogen (for countries with a very significant geological potential to dig new salt cavities) can guarantee at the end of winter such amounts of energy. Synthetic methane will retain the incomparable advantage of being able to store summer production for the winter thanks to its volumetric density 4 times higher than hydrogen, which will make it 5 times less expensive than hydrogen in this type of case of inter-seasonal storage: €5/MWhth compared to 25 for hydrogen, according to a 2020 Bomberg NEF report.
I really appreciate your lighting of the field of possibilities which sets the record straight.
I indeed believe that you are right, I sinned by optimism (and idealism...) it is my minion sin. ( )
Since we often talk about it, the solution will obviously be in an energy mix focusing on complementarity, and happy that the cost reductions in the hydrogen sector make it more and more attractive.