During summer there is generally sufficient radiation to provide almost all the domestic hot water demand, whilst during the winter the proportion produced by solar radiation is much less.
Suveperioodil on üldiselt piisavalt kiirgust rahuldamaks peaaegu kogu kuuma vee nõudlus, samal ajal kui talvel on päikesekiirguse poolt toodetud sooja vee osa palju väiksem.