Abstract
Abstract
The most widely used domestic water heaters in Bulgaria are the electric ones, with a storage tank. The main construction factors for the efficiency of the hot water boiler are considered in the present study: the temperature of water and the volume of the tank; the dimensions of the tank; the time for heating and discharge time; the insulation material and the thickness of insulation; the power of the electric heater. The average volume temperatures have been calculated analytical, the stratification effect is not taken into account. The different variants for design, insulation and the power of heater have been proposed. The results indicate for a possibility of reducing electricity for preparing hot water up to 13%. The further evaluation of the economic capability of the options has to be made.