The selection of Solar Installation       The selection of a proper type of solar installation in eastern Europe lattitudes requires fullfiling of the following conditions:

• The sun energy cannot be the only source for heating water (in polish geographics latitudes).
• The rate of providing warm water by solar collectors varies from 70% in a whole year to 100% during spring, summer and early autumn (with the proper size of installation).
• The type and size of solar installation depends on the warm water consumption.
• When choosing the type of installation, the character of building should be considered (family house, hotel, block) as well as the amounts of warm water used by the consuments.
• For the vacuum collectors the water tanks should be 30% bigger what for the same area of flat collectors.

      While counting the area of collectors for an installation the usage of 50 liter/one person/day should be taken. One square meter of collector heats up to 60 l of water. Therefore one collector with the area of 2 m² heats up to 120 l. To calculate the area of collectors and the size of water tank please use the following table:

      When the warm water usage is bigger than accepted 50 l /person/day, than the investor should take his usage of warm water and using the table, calculate the proper number of collectors.

      The choose of the size of the solar set should be made using the above given criteria and table. Of course the investor has to estimate his own average use of warm water for one person per day and with the help of installator, determine the best type of solar installation.

      While choosing the number of collectors for swimming - pool installation (L_k) and the type of plate exchanger, the following equations and tables should be used.