Steel Absorbers in Mass Production - Challenges, Opportunities and produced samples

摘要

Cost reduction of solar thermal systems is crucial for a broad, worldwide implementation of this technology. Looking at the collector costs, the absorber takes the biggest portion. There are two possibilities to minimize these costs: reduce material costs or reduce production costs (or both). In this paper, two approaches are presented, both with the goal of reducing material costs and production costs: low priced steel replaces copper and/or aluminum, and sheet metal forming technologies, well suited for mass production, replace production by welding of pipe and absorber sheet. The connections of these so-called integrated absorbers as well as the internal pressure resistance with low sheet metal thicknesses were identified as being the most important challenges. Another important issue is the coating of ready-formed, piece-good absorbers and the protection against corrosion. Assuming that these questions can be solved first economical calculations revealed for a not yet optimized process competitive costs as soon as 200 000 absorbers per year are reached.