1. Electricity Generation From Lignite John Weeda Director ND Plant Operations June 18, 2013

2. Reliable, low-cost electricity Great River Energy –2 nd largest utility in MN –28 member cooperatives 850+ employees (MN and ND) 2,751 MW owned generation 469 MW wind 4,500+ miles transmission lines $868.5 million 2011 operating revenue $3.35 billion total assets Capital markets

3. Our triple bottom line… Affordable rates Reliable electric service Environmental stewardship EnvironmentEnvironment ReliabilityReliability RatesRates

4. GRE resource portfolio

5. Types of Generation Baseload power is available for 24-7 demand –High-capacity generating plants –Plants cost less to operate when at full efficiency Peaking power is available when demand is highest –Higher cost to operate, but quick start-up to react to demand changes Intermittent power is available when supply allows –Cannot be relied upon to react to level of demand

7. GRE Power Plants

8. Lignite A low-cost abundant resource for generation of electricity

9. Over 2.0 million U.S. customers served – 850,000 Canadian customers Fort Union Lignite

10. Economic Impact Every 4 megawatts of Lignite-based Electric Generation requires about 3 jobs

11. Basics of generating electricity Commercial generating technologies Lignite as a fuel source Controlling emissions Generating electricity Summary Agenda

12. N S Lines of force (Flux) Magnet Magnetic Field Around Bar Magnet

13. Coil Magnet Meter (Galvanometer) Producing Electricity From Magnetism

14. To push blades on a shaft Which spins a magnet inside a coil of wire Producing Electricity! A source of energy such as lignite Basics of How Electricity is Made

15. Battle of the Bulbs

16. Electricity Savings The same amount of electricity used to light up one incandescent light bulb will light up how many LED bulbs? 1.2 LED bulbs 2.5 LED bulbs 3.10 LED bulbs 4.20 LED bulbs 5.50 LED bulbs

17. Electricity Savings The same amount of electricity used to light up one incandescent light bulb will light up how many LED bulbs? 1.2 LED bulbs 2.5 LED bulbs 3.10 LED bulbs 4.20 LED bulbs 5.50 LED bulbs

18. Primary Sources of Energy for Generation of Electricity Thermal generation - coal fired Nuclear generation - reactors Water - water wheel or water turbine Wind Generators- wind turbines Diesel - diesel engine Natural gas - gas turbine

19. Wind Generators Renewable, clean but intermittent

20. Basics of How Electricity is Made To push blades on a shaft Which spins a magnet inside a coil of wire Producing Electricity! A source of energy such as wind

21. Basin Electrics Wind Facilities Minot Edgeley Hyde County Chamberlain Pipestone Wilton Hancock Crosswinds PW 1 PWSD1 Day County Superior Lakota 713 MW Baldwin Oaklane SMSC Wind SD Wind Partners

22. Water-Hydro Generation Renewable, clean and reliable….but expensive and hard to build today

23. To turn blades on a shaft Which spins a magnet inside a coil of wire Producing Electricity! A source of energy such as water Basics of How Electricity is Made

24. Wind and Water Renewable but intermittent Load characteristics impact base- load units – follow the wind and water High water or wind generation – base-load units drop off

25. Diesel Generator Used for short term peaking – expensive

26. To turn a shaft Which spins a magnet inside a coil of wire Producing Electricity! A source of energy such as a diesel engine Basics of How Electricity is Made

27. Gas Turbine Natural gas is cleaner but pricing is volatile

28. To turn blades on a shaft Which spins a magnet inside a coil of wire Producing Electricity! A source of energy such as burning gas Basics of How Electricity is Made

29. Exploring lignite as a fuel source with steam turbine generators

30. Most Common Commercial Technology for Large-Scale Electrical Generation Affordable, reliable, increasingly clean

31. How is Lignite Converted into Electricity?

32. Emissions Control Equipment Hot Air Boiler Water Condenser Steam Turbine Steam Generator Pulverized Coal How Electricity is Made Using a Steam Turbine

33. Lignite Receiving & Stockpile

34. Lignite conveyed into plant

35. Pulverizers prepare the lignite

36. Bunker Burners Coal Feeder Pulverizer Lift Line Lignite-Fired Boiler

37. Photo of pulverized coal Photo of oil during startup

38. 2,400 Pounds 2,400 pounds per square inch 2,400 PSI Steam Pressure

40. Steam turbine generator

41. Generator during assembly

42. Generator stator work

43. Modern control room with computer equipment

44. Plant Transformers A.Auxiliary transformers for plant power S.Step-Up transformers for sending power out

45. Power Plant Substation

46. Lignite has some challenging characteristics

47. x = 35% Conversion Efficiency is lower due to high moisture

48. Other Challenging Characteristics Parameters of ND Lignite as found in nature –Heating value 6,000 to 7,000 BTU / Lb (other coals 8,000 to 12,000 BTU / Lb) –Ash content in ND lignite - 6% to 12% as burned –Sodium content high in many areas – contributes to challenges Deposits in boiler –Other mineral constituents

49. DryFine Can Improve Lignite Coal Creek Station –Low temperature waste heat is being used to reduce moisture in lignite –System segregates unwanted portion of fuel –Increases plant efficiency and reduces emissions

50. Lignite boiler emissions in North Dakota are controlled with up-to-date technology

51. Cutaway view of precipitator

53. 100 ND Power Plants Fitted with Scrubbers More than $800 million has been invested by Basin Electric and Minnkota to retrofit Young 1 and LOS 1 & 2 with scrubbers – now 98% of ND generation is equipped with scrubbers

54. Clean Air States Source: EPA, May 1, 2010

55. 0 200 400 600 800 1000 1200 3887 MW Total MW Capacity 1,100 900 673 650 420 100 44 Lewis & Clark Heskett Coyote Leland Olds YoungAntelope Valley Coal Creek Sources of Electricity from Lignite

56. Heat & Power Efficiency Improvements Coal Creek Station sends a mix of primary & waste steam to Blue Flint Ethanol Plant is low-cost producer of ethanol in the United States (no need to build or maintain a boiler) Spiritwood Station is a combined heat & power plant located near Jamestown, ND Will generate electricity for homes & businesses & steam for Cargill Malt When fully utilized, plant will be 66 percent efficient Compared to 30 to 35 percent efficient for most coal-based power plants

57. Capacity Requirement = 2 KW per person 650,000 persons X 2 KW per person = 1,300,000 KW or 1,300 MW North Dakota A Rule of Thumb

58. Bismarck / Mandan -190 MW Fargo / Moorhead -350 MW St. Cloud -335 MW Minneapolis / St. Paul Area -???? MW 1. 500 MW2. 1,000 MW 3. 3,500 MW4. 6,000 MW Estimated Demand

59. Bismarck / Mandan -190 MW Fargo / Moorhead -350 MW St. Cloud -335 MW Minneapolis / St. Paul Area -3. 3,500 MW Estimated Demand

60. About one-fifth of MNs electricity comes from ND -- the percentage is much higher in rural MN

61. Summary Lignite is a low-cost, abundant resource for the generation of electricity that is beneficial for the region Lignite is a secure and reliable source of energy Lignite-based power plants are in compliance with all federal ambient air quality standards

62. ??? Questions