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PowrSym History

PowrSym History

nPowrSym1 developed for TVA 1972-1985
Placed in public domain
Foundation for PowrSym Plus (also called P+)
Hourly, chronological, probabilistic
Focus on pumped hydro optimization and thermal unit constraints
nPowrSym2 developed by OSA 1985-1995

Variable head pumped hydro
Multi-area with contract path grid model
Faster computation methods
Detailed spinning and operating reserve models
LOLP and LOLE computations
Foundation for PROSYM

nPowrSym3 developed by OSA 1995-2011
Addition of NTC multi-area flow logic
Unique features for modeling wind power, cogeneration and energy storage
Fuel contract logic, natural gas pipeline grid & storage model
Power contract logic
Spot market transaction logic
Daily Operations logic and interface
Maintenance planning under uncertainty
Advanced Monte Carlo uncertainty algorithm
Optimization includes external emission costs
nPowrSym4 Nodal released in 2011
PTDF multi-area flow logic (Zonal or Nodal by Bus)
Interface to transmission models
Enhancements for multi-area adequacy studies using Monte Carlo uncertainty algorithm.
Scale up to represent very large multi-national grid systems.
Simultaneous optimization of multiple hydro and pumped hydro systems in a very large grid.
Ability to evaluate cost/benefits of transmission changes.