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J. Perelman
"Entertaining physics". Book 2.
Chapter 9. Reflection and refraction of light. Vision

SOLAR MOTORS AND HEATERS

A very tempting idea to use solar energy to heat the boiler of the engine. Make a simple calculation. Energy, every minute we get from the Sun every square inch of the outer part of our atmosphere, located at right angles to the sun, carefully counted. It seems, invariably: that's why it's called "solar constant". The value of the solar constant is equal to (with rounding) 2 small calories per 1 cm2 per minute. This heat rations regularly sent by the Sun reaches the Earth's surface is not fully: about polyamory is absorbed in the atmosphere. We can assume that square centimetre of the earth's surface, perpendicular lit up with sunlight, continually receives about 1.4 calories. Translated per square meter it is 14,000 small, or 14 large calories per minute and per second - about 0.25 b. the calories. Since 1 b. calorie, going completely into mechanical work, gives 427 KGM, the sun's rays, falling perpendicularly on a plot of land in 1 m2, could give more than 100 KGM energy every second, in other words, more than 1.3(3) horsepower.

Such work could produce radiant energy of the Sun under the most favorable conditions - at a perpendicular fall and absolute transformation. However, still ongoing attempt to directly use the Sun as a motive power were far from such ideal conditions: their beneficial effects did not exceed 5 - 6%. Implemented installations greatest efficiency gives a solar engine known physics Abbott: 15%.

It's easier to use radiant energy of the Sun to produce mechanical work and heat. Much attention is paid to this issue in the USSR. There is a special Union heliostat (Samarkand), leading to extensive research work. In Tashkent, a solar bath permeable to 70 people per day. In the same Tashkent equipped with a solar power plant on the roof of one of the houses. Here are 20 solar boilers, which are designed for 200 gallons of water and entirely provide her whole house. According to the statement of geliotekhnika, the sun will be uninterrupted warm boilers 7 - 8 months of the year. The remaining 4 - 6 months boilers can heat water only on clear days. The average efficiency of water heaters is relatively high, it is 47% (the maximum is 61%).


Solar water heating installation in the Turkmen SSR.

In Turkmenistan was tested solar refrigerator. The temperature of the cooling batteries in cameras fridge was 2 to 3° below zero at an ambient temperature of +42°C in the shade. This is the first example of industrial solar refrigeration system.


Solar store-fridge in the Turkmen SSR.

Excellent results were obtained by experiments solar melting of sulfur (melting point 120°C.). We will mention more about solar stills for producing water on the coast of the Caspian and Aral seas, Sunny vodopodyomnaya to replace the primitive Central Asian country after; solar dryers for fruits and fish, the kitchen where all meals are prepared on the Sun", and so on, All this does not exhaust the various applications of artificially captured sunlight, which will play a prominent role in the economy of Central Asia, the Caucasus, the Crimea, the Lower Volga and southern Ukraine.

Entertaining physics J. Perelman

 




System Orphus

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