In today's energy production industry, in particular in modern powerhouse operations, it is important to maintain the energy producing processes and systems at desired production levels to assure that environmental and other constraints are adhered to and operating costs are minimized.  It would be particularly desirable to maintain controllable parameters, outputs and setpoint at desired values on a real-time basis but conventional control systems typically lag behind in maintaining control since typical control systems monitor measurable quantities and attempt to control by adjusting a controllable variable, output or setpoint after the measurable quantity has gone out of control or beyond setpoint.  There is a time lag associated with this adjustment period.  During such time when a process is out of control and not at setpoint, additional fuels or other resources may be unnecessarily consumed making the system economically inefficient. 
Efficient, cost saving control systems are particularly advantageous in multi-boiler steam production systems in which the control system desirably maintains header pressure at a desired setpoint by controlling controllable devices that control parameters such as input fuel quantity which may be gases, oils, bark or other fuels, or the ratios between the incoming fuels delivered to various boilers.  When excess fuel is unnecessarily used to produce a steam header pressure that exceeds a desired header pressure setpoint, economic losses are incurred in addition to the system being out of control.  It would obviously be desirable to prevent this by maintaining header pressure at setpoint.  In particular, it would be desirable to provide an automated control system that maintains a steam header in an energy production system at a constant desired setpoint without the fluctuations associated with time lags associated with correcting an out of control system after it has gone out of control.  The present invention addresses such needs.