Fellows from Moscow company "Alten" designed an original solar energy collecting panel under the supervision of Boris Kazandzhan, Doctor of science and professor of Moscow Institute of Energetics. The panel absorbs thermal energy of solar radiation and redirects it for heating water.
      The idea of heating water by means of solar radiation isn`t, of course, a new one. Painted black water tanks with self-made shower can be seen near almost every summer cottage. During summer these tanks provide warm shower for their owners, who haven`t got a gas or electric water heater. The drawback of such tanks is that water inside them remains quite cool even in a very hot summer day and cannot be used to heat the house.
      The problem is that solar radiation is very difficult to be collected and stored. Ordinary items, like water tank or a bench located at the sunny side of a pond, absorb energy of visible light, which warms them. Then they emit heat to the surrounding space almost immediately in the form of infrared radiation and convection.
      In order to raise effectiveness of solar radiation absorbance scientists use original selective multi-layer coating, with titanium carbide as a main component. Its external side is dark to absorb light better. But the coating hardly emits heating energy after it has been heated. Thus, given coating allows collecting solar energy of visible and near infrared spectral regions, which contain 90% of solar energy, and at the same time storing energy of the heating radiation without emitting it.
      Trapped heat is transmitted to water, which runs along copper pipes, embedded in aluminum profiles covered with said coating. These pipes form so-called absorber. However, water can be replaced with any other heat-carrying agent, but water is the cheapest one.
      Absorbers are covered with special plastic cases, which reduce heat losses due to convection. These cases are made of polycarbonate with honeycomb structure. Theses cells are hollow, that`s why the air inside them is motionless, which allows perfect storing of heat. Polycarbonate transmits light, cannot be heated and gives no shaded, thus doesn`t hamper unit operation.
      Thus, a single 2 sq. m collector is able to heat up to 150 liters of water up to 60-70 degrees Centigrade. Water can even be boiled, if necessary. Several units can provide hot water and heating for a small cottage. In Moscow region, known for its moderate climate, for example, these units can work in case of long warm season – early spring to late autumn. They won`t work in Russia in winter, even if their effectiveness would reach 100%. In mild climate of Europe these units will work all the year round. In a short while a house with described heating system will be built in the city of Sochi, situated in the south of Russia, in a humid subtropical zone. Its façade will be decorated with solar absorbing panels, which look very picturesque. This house will have hot water supply all the year round.
      
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