Many of us wanted to turn a satellite TV dish into a concave mirror. Now we see how a mirror dish focuses the solar radiation, and it is obvious that this point will have a high temperature, which can set fire to wood, or blow something up, or melt metal, or for cooking. Usually a satellite dish is turned into a mirror through sticking small pieces of mirrors, or sticking reflective films, or some other way.
Our concave mirrors appear to be very cheap, and therefore it seems to us that they are capable of producing cheap thermal energy and electricity. That is why we ask the question, can we install thousands or millions of our cheap mirror dishes, which will give us a lot of cheap thermal energy and electricity so that such solar power plants are better than thermal and nuclear power plants and solar panels, and the answer to this question will surprise you.
Now I am showing the 1st option, which suggests that a mirror dish would focus solar radiation onto a similar Stirling engine. These are examples of the 1st option from various bloggers, when a Stirling engine converts the thermal energy into rotation of an electric generator.
The 2nd option suggests placing a small solar panel here, similar to how this mirror dish focuses solar radiation onto this photovoltaic panel which is water cooled.
The 3rd option is used by this Indian solar power plant, where the solar radiation from the mirror dishes is focused on these cast iron receivers and heats them to a temperature of about 400 ⁰C. The thermal energy turns water into steam which moves through these pipes to this turbine with an electric generator.
Unfortunately, those three options are not suitable for us because our goal is victory over thermal and nuclear power plants, and therefore the cost of our solar electricity should be about 5 cents / kWh. In addition, I remind you that we want our mirror dishes to be better than solar panels.
That is why we must pay attention to the fourth option, which is used by solar power plants of this type. We know that solar radiation heats these pipes, which are filled with thermal oil with a temperature of more than 300 ⁰C. This hot oil moves through these pipes to the center of the solar power plant, where a proportion of its thermal energy produces steam for the turbine, and the rest of the oil energy heats thousands of tons of the substance in these thermal storages to a temperature higher than 300 ⁰C. Then, in the evening or at night, this hot substance produces steam for the turbine, and this is one of the advantages over solar panels, which produce electricity only when it is sunny.
In addition, one of my old videos described how that hot substance can produce electricity for several non-sunny days in a row, if that substance is concrete, gravel, sand or other cheap materials. The next advantage over solar panels is the ability to generate electricity during a non-sunny winter as good as during a sunny summer, if the heat storage is a large mass of soil or cheap waste, as described in this old video.
In addition, my previous video described how similar solar power plants can provide a lot of cheap thermal energy for industrial processes for factories, and my future videos will describe the possibilities of supplying the cheap thermal energy for district heating and greenhouses.
The use of thermal oil is not experimental, but a well-proven technology, which has been in use for more than 20 years, and investors have already built more than 100 such power plants with a total cost of about 40,000,000,000 USD.
Unfortunately, these mirror systems generate expensive thermal energy, about 2 cents / kWh, and therefore their electricity is expensive. That is why thermal energy from our mirror dishes should be 4 times cheaper, about 0.5 cent / kWh.
So, our cheap dish should have a similar receiver, which will heat thermal oil to a temperature higher than 300 ⁰C. These are more decent options for receivers for heating liquids.
Now we see that a dish with a receiver should rotate from morning to evening according to the movement of the sun across the sky. This rotation is done by a device called a "Dual-axis tracker", and this device is widely used as a location for solar panels.
Of course, our solar power plant will consist of a large number of mirror dishes,
which heat hundreds of thousands of tons of cheap substance to approximately 300 ⁰C during solar hours. The thermal energy will generate steam for a turbine both day and night.
