Renewable Energy Overview

1. Renewable Energy Overview Robert M. Neilson, Jr. Renewable Energy & Power GNEP Physics Teacher Workshop July 18, 2007

2. Electricity Generation Take Away Message: All energy generation technologies have their advantages and disadvantages What one chooses depends upon one’s needs and perceptions

3. Electricity Generation Technologies • Petroleum • Coal • Natural Gas • Nuclear • Renewables - Biomass - Geothermal - Hydropower - Solar - Wind

4. U.S. Electricity Production (2005) Renewable Sources

5. Wind Energy Has A Long History The Egyptians used wind energy to sail on the Nile River in 2000 B.C. The Chinese used vertical axis windmills to grind grain and pump water over 2,000 years ago

6. Wind Energy Has A Long History The French were the first to use the “classic” windmill in 1180 Windmills were widely used for pumping water in the settling of the American West

7. Wind Energy Has A Long History In the United States, the most notable early example of the use of a wind turbine to generate electricity was built by Charles Brush in Cleveland, Ohio in 1888

8. Wind Energy Has A Long History Today, wind turbines as large as 5 MW are used for generating electricity

9. What is the Origin of Wind? Global winds result from pressure differences across the earth’s surface due to the uneven heating of the earth by solar radiation • Spatial variations in heat transfer to the atmosphere result in pressure variations • Air moves from high to low pressure areas, creating wind

10. Local Wind Characteristics Local wind speed and direction are affected by a number of factors: • Temporal variations (annual, diurnal, short-term) • Terrain effects • Obstacles • Height above the ground

11. Wind Power is a Strong Function of Velocity P = Cph(1/2)rpR2V3 Where Cp = power coefficient (ratio of rotor power to power in the wind) h = mechanical drive train efficiency r = air density R = radius of rotor V = wind velocity

12. Wind Power Classification

13. Initial Area Wind Assessment • Collect initial data from multiple sources (i.e., talk to people, look for existing data, wind maps, etc.) • Look at the lay of the land, prevailing wind direction, and vegetation (flagged trees, etc.) • Plan for collecting wind data (number, type, and height of instruments, cost, permits) • Quality wind data is important (people’s perception of “windy” is not good enough)

14. Does This Area Look Windy?

15. Anemometer Tower Instruments Data Logger Anemometer and Wind Vane

16. Anemometer Tower Installation

18. Idaho Anemometer Loan Program Program is administered by INL, IDWR-Energy Division, and BPA State and private land Data is available to the public www.inl.gov/wind/idaho

19. Idaho Wind Map

20. Small (10 kW) Homes Farms Remote Applications (e.g. water pumping, telecom sites, icemaking) Intermediate (10-250 kW) Village Power Hybrid Systems Distributed Power Large (250 kW – 5 MW) Central Station Wind Farms Distributed Power Wind Energy Comes in Different “Sizes”

21. Wind Turbine Components Blades Hub/Shaft Gearbox Generator Yaw Control Brake Nacelle Tower Tower Foundation

22. ANEMOMETER NACELLE GENERATOR MAIN BEARING LARGE TURBINE DIAGRAM MAIN SHAFT BLADE OIL COOLER GEAR BOX TOWER HUB

23. Wind Turbine Rotor Diameter Boeing 747-400 3.6 MW 104 m (341 ft) Wingspan 64.4 m (211.5 ft) 2.5 MW Length 70.7 m (231.9 ft) 88 m (289 ft) 1.5 MW 70.5 m (231 ft) 850 kW 52 m (171 ft) Rotor diameter

24. Why Is Utility-Scale Wind “Different”? Intermittent • Low capacity factor • Scheduling penalties Remote (and location specific) • Constrained flow to major load centers Low Energy Density (but “fuel” is free) New • Not part of established processes • NIMBY

25. Wind Energy Environmental Impacts Air Emissions (None!) Avian Issues Visual Impact Noise Electromagnetic Interference Land Use Flora and Fauna Safety

26. Air Emissions

27. Avian Impacts Bird kill has been an issue at Altamont Pass, CA (Bats are a concern at some eastern sites) Mitigation Concepts • Avoid migration corridors • Alternate tower designs (monolithic vs. lattice towers) • Fewer, larger turbines • Prey base management • Bury electrical lines

28. Visual Impact Modern Wind Turbines are Large! Viewshed Alteration Mitigation Concepts • Turbine placement (use landscape to advantage) • Design, number, and arrangement of turbines • Wind turbine color • Lighting

29. Wind Turbine Noise Aerodynamic noise Mechanical noise Noise from an operating wind farm is 35-45 dB(A) at 350 m (1,100 ft) – comparable to a refrigerator Mitigation Concepts • Use of noise reducing blades and components • Distance from the observer

30. Electromagnetic Interference Wind turbines can interfere with television, radio, microwave, and radar transmission Blade construction material, geometry, and rotational speed are important Mitigation Concepts • Composite blades • Blade geometry should avoid sharp corners/edges • Avoid locating turbines in microwave communications paths and radar line-of-sight

31. Land Use Impacts Actual land required for turbines and access • On flat terrain, a wind farm requires about 60 acres per MW, but only 5% of the land is occupied by turbines, roads, and other equipment • On ridgelines (hilly terrain), a wind farm may require as little as 2 acres per MW Land use compatibility

32. Flora and Fauna Impacts Reduction of habitat Mitigation Concepts • Ecological survey • Avoid disturbing sensitive habitat (e.g., nesting areas)

33. Safety Blade Throw Falling or Thrown Ice Tower Failure Attractive Nuisance Mitigation Concepts • Distance to wind farm boundary • Prohibit maintenance during adverse conditions • Fencing

34. Economics of Wind Energy Generating Costs • Highly dependent upon wind resource characteristics • Capital cost • O&M costs • Financing cost Avoided Costs • Fuel savings

35. Cost of Wind Energy (Capital Cost x FCR) + O&M Costs COE = Annual Energy Production Where COE = Cost of Energy FCR = Fixed Charge Rate (present value factor including debt and equity costs, taxes, and insurance) O&M = Annual Operations and Maintenance costs Cost of Energy is about $0.04 – $0.08 per kWh Note: Cost does not equal Price

36. Installed U.S. Wind Power Capacity (1981 through 2006) Installed Capacity, MW Year

37. Federal Incentives Renewable Energy Production Credit (PTC) • 1.9 cent/kWh tax credit (first 10 yrs of operation) Public Utility Regulatory and Policy Act (PURPA) • Required utilities to purchase power from independent generators for “avoided cost” Federal Purchase Requirement • Sets renewable energy purchase requirements for electric energy consumed by the Federal government (not less than 3% 2007-09; 5% 2010-2012; 7.5% 2013 and thereafter)

38. Other Incentive Strategies Renewable Portfolio Standard (RPS) Renewable Energy Credits (REC) System Benefit Charge Green Pricing/Green Tags Emission Credits/Carbon Tax Interconnection, Transmission, and Distribution Rules

39. You Know Why and What, but How? • DEVELOPING WIND RESOURCES: • Prospect • Collect anemometer data • Analyze wind data • Resolve permitting and legal issues • Obtain electrical interconnection study • Obtain Power Purchase agreement • Arrange financing • Build and operate a wind farm • TOTAL TIME, start to finish • Three to five years

40. Wind Energy Information Sources WIND U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy www.eere.energy.gov/windandhydro Idaho Department of Water Resources – Energy Division www.idahowind.org American Wind Energy Association www.awea.org OTHER RENEWABLES www.energyforkeeps.org

41. Characteristics of Different Resource Types From E3 Inc. Presentation to Idaho Legislative Subcommittees (Sept. 06)

42. Utility-Scale Electricity Technology Characteristics