Department of Mechanical Engineering, University of California, Merced, CA 95343, U.S.A.
A number of applications, such as sterilization, steam cleaning, and food drying, among others, require low-
grade steam for their operation. Steam is usually obtained from fuel-combusting boilers which produce carbon
emissions by means of combustion of natural gas, propane, or other fuels. Evacuated-tube solar collectors also
produce steam at temperatures between 200 °C and 300 °C. This paper analyzes the generation of low-grade
steam (between 100 °C to 115 °C) with the use of non-concentrated minichannel-based solar collectors. In
the past, the authors have successfully implemented aluminum minichannel-based solar collectors to generate
hot water. Copper-based minichannel tubes are utilized in this study to show steam generation performance
under conditions of forced pumping and thermosiphon operation.