Why is AirHES still cooler?
I have long wanted to write this post in order to show with a simple example the main advantage of AirHES compared to other renewable energy sources - the ability to collect dispersed energy using the forces of nature itself.
Let's say that you are an investor and are thinking about what type of renewable energy to use. We will limit ourselves to Solar Panels (Photovoltaic, PV) and AirHES. Let's say that you can choose the place on Earth where this RES will work best. Then it is obvious that PV will work best at maximum insolation (solar irradiance), for example, in Aswan. Dividing the average daily insolation of 6.34 kWh/m2 by 24 hours, we get an average power of 264 W/m2, which, with the current maximum efficiency of 25%, gives an electrical power of ~66 W/m2 at a PV price of ~$100/m2, i.e. costs ~$1500/kW.
For AirHES, we will choose some place with the maximum amount of precipitation and cloud height - ideally, on the equator, for example, in Latin America or Indonesia, where ~3 m of precipitation falls per year. Then, assuming that we can collect all the energy of these rains, we get:
~3 m (rains) * 1000 kg/m3 * 10 m/s2 (g) * 5000 m (cloud height) / (year in s)
i.e. ~5 W/m2 at the price of rain collection fabric ~$1/m2, i.e. costs ~$200/kW.
It would seem that AirHES wins in terms of unit costs, but this is a Pyrrhic victory! If you need to build a real station with gigawatt parameters, then it seems completely unthinkable to hang some gigantic fabric under the clouds in order to collect rain from all this vast area - it is obvious that this is practically unrealizable... But, the most important thing, this no need!
It was supposed to collect vertical rain in the early ideas of the AirHES, proposed by prof. A.S. Baibikov. Further development of the idea led to the modern concept of the AirHES, which itself collects precipitation from the clouds directly from the horizontal flow of microdroplets, and does not wait until these drops begin to fall down in the form of rain. At the same time, nature itself works several times to help the AirHES, collecting the initially dispersed energy of the water cycle:
- Water evaporated by the Sun rises in the form of steam, cools and condenses into microdroplets, and concentrates in clouds in a vertical zone ~1 km.
- These clouds are carried by the wind to a distance ~1000 km, thus collecting evaporated moisture from the vast territory of such a "belt" on earth.
- These microdroplets are collected by meshes or “sails” of the AirHES over a limited vertical area, for example, ~1 km2, i.e. 1 km horizontally by 1 km vertically, passing the clouds through oneself.
- The resulting “condensate” of microdroplets drains by gravity from the "sails" into the drainage, and then into a hose with a diameter ~1 m, creating a super-powerful flow with a head ~5 km.
Thus, Nature itself collects the energy of the Sun from a vast territory ~1000 km2, in fact, into one powerful stream that enters the hydro turbine of the AirHES!
Let us now recalculate the parameters of such an AirHES, taking into account that meshes or “sails” do not capture the entire flow of microdroplets (for more details, see the article on Optimization of mesh) - according to experimental and calculated data, the efficiency of such meshes is from 10 to 60%. Let's take 20% for calculation. Then the flow power will decrease by a factor of 5 and will be ~1 W/m2 (here m2 is, as before, m2 of the earth's surface). I.e. an AirHES with a capacity of ~1 GW collects evaporated moisture from just this "belt" ~1000 km long and ~1 km wide, i.e. ~1000 km2! But at the same time, it needs a vertical mesh of only ~1 km2 at a cost of ~$1M - the costs are lower by another 3 orders of magnitude (~$1/kW with 1000 W/m2 of mesh!) and this station practically does not take up space on the ground!
For comparison, a ~1 GW PV plant would cost ~$1.5 billion and occupy ~15 km2 on the ground!