K: the number of time intervals
Cj : the startup cost of unit j
Ej : the shutdown cost of unit j
Aj : the fixed cost of unit j
Bj : the variable cost of unit j
Pj
: the minimum output power of unit j
Pj : the maximum output power of unit j
Sj : the maximum rampup power increment of unit j
P
0
j
: the output power of unit j just before the first period of the planning
horizon
Tj : the maximum rampdown power decrement of unit j
V
0
j
: a binary constant that is equal to 1; if unit j is online the period
preceding the first period of the planning horizon, and 0, otherwise
J: the number of power units
Dk: the demand in period k
Rk: the amount of required reserve (over the demand) in period k