For the 30 MWe SEGS VI parabolic trough collector plant, one task of a skilled plant operator is to maintain a specified set point of the collector outlet temperature by adjusting the volume flow rate of the heat transfer fluid circulating through the collectors. For the development of next generation SEGS plants and in order to obtain a control algorithm that approximates an operator's behavior, a linear model predictive controller is developed for use in a plant model. The plant model is discussed first in this work. The performance of the controller is evaluated for a summer and a winter day. The influence of the control on the gross output of the plant is examined as well. (C) 2003 Published by Elsevier Ltd.