A new technique was developed to enhance the heat transfer more than with fully developed turbulent flow. Commonly the offset rectangular plate fins are used in heat exchangers; they alternate with the periodically interruptions. The fluid homogenization depends on the length of interruption, and new velocity and thermal boundary layers were developed at each encountered offset fin located downstream of interruption. This technique characterizes a higher heat transfer than in fully developed turbulent flow. In the present work this technique of periodically interrupted offset fins is adapted to solar collector. An experimental investigation carried out showed the generated enhancement of thermal performance. The offset rectangular plate fins, mounted in staggered pattern, are oriented parallel to the fluid flow and are soldered to the underside of absorber plate. High thermal performances are obtained with low flow friction and in consequence a low electrical power consumption by the fan in comparison to the flat plate collector.