primary receiver these hot spots may have a temperature exceeding the failure threshold for the primary receiver material in addition the temperature variation between adjacent portions of the primary receiver may induce thermal stresses due to differing amounts of thermal expansion that could lead to eventual failure by ensuring a uniform heat flux distribution the highest possible temperature can be achieved for the working fluid e g superheated steam without localized hot spots that may damage the primary receiver in accordance with this goal an exemplary embodiment of the present invention seeks to maintain a uniform heat flux distribution on the primary receiver by dynamically controlling the focal points of heliostats fig3 a shows an example of a solar energy based power system having a single tower 302 including at least a primary receiver or receiver section and a secondary receiver or receiver section surrounding the tower 302 is a field 304 of heliostats individual heliostats not shown although the field 304 is shown to be square in fig3 any shape may be employed for the heliostat field such as but not limited to oval polygonal crescent shaped and other non regular geometric shapes furthermore although the tower 302 is shown centered in the field 304 the tower 302 may be located elsewhere.