Correction of the concentrated sunlight spot's drift of the IER-UNAM's solar furnace

This paper discusses the methods implemented for the solution of the drift and backlash problems in the heliostat of the High Radiative Flux Solar Furnace recently built at the Renewable Energy Institute (former Center for Energy Research) of the National University of Mexico (IER-UNAM), located at the geographical coordinates 18°50′24″ North latitude and 99°15′00″ West longitude. To solve the observed drift, several algorithms were analyzed for the calculation of the solar vector, and a closed loop through an electronic device (peephole) was implemented which makes corrections to the position of the heliostat. Using the peephole, drift heliostat decreased significantly; 70% in the horizontal direction and 63% in the vertical direction relative to the no use of peephole. The backlash was corrected by means of unbalancing the heliostat