SOLAR DRINKING WATER SYSTEMS - DESIGNING AND DIMENSIONING FOR RESIDENTIAL BUILDINGS - THE NEW VDI GUIDELINE 6002

摘要

The number of solar heating systems is increased in the last years. Especially systems to heat drinking water are more and more installed on the roofs. This welcome trend based on best functionally technical standards, however these systems have to be dimensioned reasonable to get best function and economical operation. The dimension of a drinking water heating system depends on the user behavior. Residential buildings are one of the main applications for solar water heating systems. So this guideline is restricted to this special application. This report presents the demands of the guideline VDI 6002 (planning stage), concerning the designing and dimensioning of solar water heating systems for residential buildings, first time to the public. The guideline is aimed at the following groups: planners of buildings and complexes, operators of buildings and complexes, energy consultants and for other public and non public authorities. In the first place the guideline is written about big installations, but the main results are also suitable for onefamily houses. The guideline first gives valuable hints to avoid faults and so the main components (tubes, collectors, pumps, heat exchangers, tanks, safety installations, etc.) in a solar drinking water system are discussed. In Europe the hygienic standards of drinking water are strictly recommended. Consequently there are problems in Germany, if the installations, especially the hot-water tanks are too big. The fundamental further aspect is the dimension of the collector areas and the volume of the water-tanks. First time it will be said, that the water consumption of warm drinking water has to be reduced to round about 20% in summertime. A lot of studies demonstrate that most solar plants are over dimensioned because of the too high recommended drinking water consumption. At last the rules concerning economy and efficiency are presented and some hints about the commissioning and the maintenance of solar heating systems are introduced.