Use the cost data for the six-bus base case, and the power flow and generator output data presented in Figures 11.3 (Cases 1, 2, and 3) that illustrate the wheeling of 20 MW between bus 3 and bus 4. We want to compute an estimate of the utility's net costs under all three cases. Let
Net cost=total production cost for all generators-charges for wheeling Note that the total production cost for each case is given in the tables just after Figure 11.3. Produce a table that shows the power generation for each unit and the total system operating cost in $/h for the three cases: the base case and the two wheeling cases. For the two cases with 20 MW being wheeled, compute the charges for wheeling as (20 MW × the SRMC) for wheeling given in the chapter. These are
13.2494 - 12.376 = 0.8734 for the unconstrained case and
16.4711 - 12.2015 = 4.2696 for the constrained case.
These charges represent income to the utility and reduce the total operating cost. (The question is really: "Does the use of the SRMC for wheeling only recover additional operating costs for the wheeling, or does it make an added profit for the utility?" Remember, this is only one example.)
