In optimization models, the Unit Ramping Cost table slot has been removed from the Thermal object (the Ramping Cost series slot is still available). Users still wishing to utilize the Unit Ramping Cost slot can select it from the Ramping Modeling method category on Power Reservoir objects. See the Optimization section of the release notes for more details.

Prior to this release, a bug was preventing the Maximum Iterations on accounting slots from being checked. This bug is fixed for RiverWare 4.0 so models will now abort if an accounting slot is set more than the maximum number of iterations on a given timestep. It is possible that existing models have been violating this restriction all along. If this is the case, these models will now abort. The user will need to increase the Maximum Iterations on accounting slots for the model to run completely again. This is done by selecting View->Simulation Run Parameters from the Run Control dialog box.