Utilizatiｏn of Solar Energy with Solar water Heaters in Kitami

摘要

Experiments on the utilization of solar energy in the city of Kitami were performed with a flat type solar water heater，available on the market， and a focussing type solar water heater of the authorsu27 own making. A Sekisui Heater was used for the flat type solar water heater，and the period of measurements lasted 7 months， from May the 19th tiｌｌ November the 19th，1970. The period of measurements on the focussing type solar water heater lasted about two months， from october the 1st tiｌｌ November the 25th，1970. The folｌowing resuｌts were obtained. (1)The flat type solar water heater can reliabｌy be used from June to September.　(2)The solar water heater，incase of being used in a cold region， has to be improved as far as the heat insulation and the draining mechanism are concerned and the expansion of the receiving area of sun rays is also needed. 　(3)The efｆiciency of the focussing type solar water heater is less than that of the flat type solar water heater，caused by the low reflection factor of the mirror