This lecture covers the fundamentals of solar energy conversion devices, including the energy states in matter, basics in thermal transport, exergy analysis in solar systems, solar thermal collectors, optics, concentrating technologies, solar electricity, semiconductors, electrochemistry, and solar fuels. The lecture also delves into the technology behind solar thermal collectors, online classes, and various labs related to electrochemistry. It discusses the basics of electrochemistry at different temperature ranges and the principles of solar fuels by thermochemical and photo-electrochemical paths.