1 Power Resource Management with assistance of Kevin Gawne Karl Reznichek and Dave Cormie

2 Basics of Hydroelectric Generation

3 Hydroelectric Generating Station Flow Forebay Tailrace Powerhouse Dam Spillway

4 Cross Section of a Typical Hydro Unit Forebay Tailrace Generator Head (H) Flow (Q) Efficiency (e) Power = Flow x Head x efficiency x constant Turbine Vertical Axis

5 Introduction to Manitoba Hydro System

6 Nelson and Churchill River Drainage Basins

7 HVdc System Map Total Installed Capacity 5480 MW Jenpeg Selkirk Brandon Grand Rapids Limestone Long Spruce Kettle Laurie River Kelsey Pine Falls Great Falls McArthur Falls Seven Sisters Pointe du Bois Slave Falls Lake Winnipeg Southern Indian Lake Split L. Stephens L. 70% of Capacity on Lower Nelson River: - Kettle (1232 MW) - Long Spruce (1023 MW) - Limestone (1330 MW) Jenpeg Cross Lake Kiskitto Lake Kiskittogisu Lake Playgreen Lake Playgreen Lake Cross Lake Norway House Warren Landing Lake Winnipeg 2-Mile Channel 8-Mile Channel Ominawin Bypass N Nelson R West Channel Nelson R East Channel Lake Winnipeg Regulation More than 90% Hydraulic Based Generation

8 Interconnected Transmission System

9 Candidate Plants - Wuskwatim (200 MW) - Gull (630 MW) - Conawapa (1400 MW) Potential New Generation and HVdc Winnipeg Wuskwatim Gull Conawapa New HVdc

10 Variability of Hydraulic Supply (inflows measured as energy equivalent) 1940/1941 Drought Manitoba Consumption

11 Wet: Winnipeg River June 8-10, 2002 Precipitation

12 Wet …

13 Wet: June 2002 Upper English River at Sioux Lookout

14 Wet: Spill at Pointe du Bois, 2002

15 Dry: Winter 02/03 Precipitation % of normal

16 Dry: Lake of the Woods, 2003

17 Flow Forecasting

18 Load Forecasting Load is related to time of year, day of week, hour of day, temperature, other

19 Market Forecast YEAR

20 WINTER SUMMER DEMAND WATER SUPPLY DEMAND SUPPLY AND DEMAND Water Supply & Manitoba Electrical Demand

21 Manitoba and Export Demand (a typical week) MW MondayTuesdayWednesdayThursdayFridaySaturdaySunday EXPORT Real Time Day Ahead Forward Manitoba

22 Power Resource Management

23 Power Resource Management Manage Manitoba Hydro’s system of reservoirs, hydro stations, thermal stations, and tielines in the most economic and secure manner possible Meet or exceed regulatory requirements Consider environment and waterway users

24 - domestic load - exports - outages - losses - inflows, storage, coal, gas - imports - plant capability Uncertainty Licences Social and Environmental Power Resource Management SUPPLY DEMAND Resource Management Decisions

25 Decisions Hydraulic stations (generate or spill?) Thermal stations (generate?) Reservoirs (store or release?) Energy (buy or sell?)

26 Uncertain Aspects Inflows into reservoirs Manitoba load Ice effects on river hydraulics Export/import market prices Thermal fuel costs

27 Key Resource Management Decision - Lake Winnipeg Outflow

28 Decision Considerations Multi-stakeholder –e.g. Lake of the Woods Multi-jurisdictional –Saskatchewan R. (AB, SK, MB) –Winnipeg R. (USA, ON, MB) Environment Transportation Recreation Addressed through: Boards, Licences, Agreements, Programs, Facilities, Operating Guidelines

29 System Model

30 System Model Decision variables reservoir storage (STt), turbine release (Rt), spill (St) produced energy (HEs,t), imported energy (IEs,t), and exported energy (EEs,t).

31 System Model Objective function HCs,t - the hydro energy production cost; EBs,t - the export energy benefit; ICs,t - the import energy cost; SCt - the cost of spilling water; and BT - the benefit from saving the water for future production.

32 System Model Nonlinear hydro production function Linearized by assuming a constant value for the head (H) and efficiency (e). Iterative Linear Programming optimization

33 System Model Other constraints –Flow continuity –Tieline load –Supply and demand

34 System Model –Minimum storage –Maximum storage –Hydro energy relation to release

35 System Model Linear Programming Optimization –100’s of decision variables –1,000’s of constraints –1,000,000’s of dollars benefits for the utility and residents of Manitoba Optimal use of power resource Taking advantage of the system structure Taking advantage of energy market

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