This paper describes the design and performance of a convex type of solar water heater. The main purpose of a convex solar collector is to accomplish static tracking for the sun radiation without additional cost, that is, to collect energy efficiently in the early and later times of the day due to the low angle of incidence with a high percentage of solar radiation perpendicular to the collector plate. Two adjacent types of collectors, flat plate and convex type with the same projected area, were constructed and tested under the same conditions. Comparisons were made of the lumped efficiency and useful energy under different conditions. The efficiency and the useful energy were considerably greater for the convex type collector than for the flat plate collector under the same environmental and insolation conditions. An additional 45% energy gain was achieved from the convex type compared to the flat plate collector.