Computer simulation studies of temperature control techniques for the heat transfer fluid in parabolic trough solar collector fields are discussed. In particular, it addresses the rather stringent temperature control requirements associated with thermal electric power generation or cogeneration systems. Computer models representing the fluid temperature dynamics of the collectors and interconnecting piping were developed and integrated with dynamic models of control elements to obtain a simulation of a closed loop control system. A specific control configuration was chosen consisting of a flow control valve and one or more temperature sensors to control the flow in each row of collectors. Various control algorithms were evaluated for stability and static errors, and time responses to startup transients and to partial and full collector cloud shadowing transients were obtained. The results indicated that the temperature control requirements can be satisfied using readily available components.