Solar Water Heater Sizing Calculator

Size solar thermal water heating systems based on daily hot water demand and solar fraction.

Daily hot water demand.
gal/day
Average cold water temperature.
F
Desired hot water temperature.
F
Desired solar contribution (0.5-0.8).
Average peak sun hours per day.
hrs

Results

Daily BTU Required-BTU/day
Collector Area-sq ft
Storage Tank Size-gal
References: ASHRAE 90003; SRCC OG-300; Solar Rating & Certification Corp