The results of complex theoretical and experimental investigations of applicability of the thermochemical cycles based on reversible catalytic reactions of the "Methane reforming-methanation process" for the needs of concentrated solar energy utilization are presented. The data obtained evidence for practical possibility to obtain sufficiently high efficiency for both primary conversion of the concentrated solar light into well-stored energy of chemical bonds and conversion of the latter into high-potential heat. The experimentally registered values of efficiency exceeding 40% for the first process and 23% for the closed-loop system which allow obtaining heat at more than 700°C. © 1990.