The paper describes a coordinated approach to short-term hydro schedul
ing and dispatch that has been developed as a part of the Tasmanian Hy
dro Electric Commission's (HEC) new Energy Management System (EMS), wh
ich is being delivered by Landis and Gyr Energy Management, Tasmania's
hydro generation system consists of 40 reservoirs in six river catchm
ents, The daily water release for each plant is scheduled using the HE
C's mid-term operation policy, The Hydro Scheduling and Commitment (HS
C) function schedules the hydro units on a half hourly basis so that t
he allocated water release maximizes the energy production. This maxim
ization of energy production is achieved by maximizing the head and th
is ensures that operation is always as close as possible to maximum ef
ficiency. Mixed Integer Linear Programming is used with detailed model
of the interconnected hydro system to determine the half-hourly opera
tion schedule, The Hydro Economic Dispatch (HED) function is used to i
mplement the schedules produced by HSC in the real-time operation. The
HED also uses a detailed model of the hydro system with a Linear Prog
ramming algorithm to ensure that each unit operates as close as possib
le to its head-dependent theoretical maximum efficiency point while me
eting the desired storage levels specified by the HSC solution. HSC an
d KED have been tested against a number of operational scenarios and w
hen it is fully integrated within the new EMS it is expected to yield
annual stored energy savings up to 0.5% through more efficient hydro-e
lectric system operation. It is expected to also provide additional sa
vings by fostering improvements to the mid-term operating plan.