1. College of Engineering Discovery with Purpose www.engineering.iastate.edu August 23, 2011 Introduction to Wind Energy James McCalley (jdm@iastate.edu)jdm@iastate.edu ENGR 340, Wind Energy, System Design and Delivery

2. College of Engineering Bookkeeping Field trip: Meet in alley just next (south side) to Coover Hall at 4:55 pm Tuesday. We will leave at 5:00 sharp so do not be late. 2 Homework Read chapters 1-2 of DOE20by2020 report (by today) Read chapter 4 of DOE20by2020 report by Tuesday Continue reading Wind Intro notes from course website (they have been updated).

3. College of Engineering Overview Preliminary energy concepts Background on US wind power growth Policy issues for wind energy Wind energy in context Grand challenge questions 3

4. College of Engineering Some preliminaries Power: MW=1341HP. Energy: MWhr=3.413MMbtu (10 6 btu); 1btu=1055joules E=P×T Run 1.5 MW turbine at 1.5 MW for 2 hrs: 3 MWhrs. Run 1.5 MW turbine at 0.5 MW for 2 hrs: 1MWhrs 4 Power, PTime, TEnergy, ECapacity, P rated Time, t  Power, P(t) 1.5 MW If P varies with t: Capacity factor: A lawnmower engine is 3HP (2.2kW or 0.0022 MW). Typical car engine is 200 HP (150kw or 0.15MW). Typical home demands 1.2kW at any given moment, on avg. 1MW=10 6 watts  10 6 w/1200w=833 homes powered by a MW. Ames peak demand is about 126MW. The US has 1,121,000MW of power plant capacity. 1 gallon gasoline=0.0334MWhr; Typical home uses 11000kWhrs=11MWhrs in 1 year (about 1.2kW×8760hrs). 1 ton coal=6MWhrs. Actual annual energy production as a percentage of annual energy production at P rated

5. College of Engineering Background on Wind Energy in US US Generation mix Wind & renewables are 3.6% by energy. Source: AWEA 2010 Annual Wind Report 5

6. College of Engineering Background on Wind Energy in US U.S. Annual & Cumulative Wind Power Capacity Growth Source: AWEA 2010 Annual Wind Report 6 But what happened in 2010?

7. College of Engineering Background on Wind Energy in US 2010 is different! Source: AWEA 2010 Third Quarter Market Report 7

8. College of Engineering Background on Wind Energy in US Percentage of New Capacity Additions. Source: AWEA 2010 Annual Wind Report 8 N. GAS WIND

9. College of Engineering Background on Wind Energy in US U.S. Wind Power Capacity By State 9 Source: AWEA 2010 Third Quarter Market Report 10 of top 14 are in the interior of the nation

10. College of Engineering Background on Wind Energy in US U.S. Wind Power Capacity By State 10 Source: AWEA 2010 Third Quarter Market Report 10 of top 14 are in the interior of the nation

11. College of Engineering Background on Wind Energy in US U.S. Wind Power Capacity By State 11 Source: AWEA 2011 First Quarter Market Report

12. College of Engineering Background on Wind Energy in US 12 Source: AWEA 2010 Third Quarter Market Report Source: AWEA Wind Power Outlook 2010

13. College of Engineering Background on Wind Energy in US Market share of total 2008 wind installations Source: AWEA 2009 Annual Wind Report 13

14. College of Engineering Background on Wind Energy in US Ownership by company and by regulated utility Source: AWEA 2009 Annual Wind Report 14

15. College of Engineering Background on Wind Energy in US Wind plant size Source: AWEA 2009 Annual Wind Report 15

16. College of Engineering Background on Wind Energy in US 29 states, differing in % (10-40), timing (latest is 2030), eligible technologies/resources (all include wind) 16 State renewable portfolio standard State renewable portfolio goal Solar water heating eligible * † Extra credit for solar or customer-sited renewables Includes non-renewable alternative resources WA: 15% by 2020* CA: 33% by 2020 ☼ NV : 25% by 2025* ☼ AZ: 15% by 2025 ☼ NM: 20% by 2020 (IOUs) 10% by 2020 (co-ops) HI: 40% by 2030 ☼ Minimum solar or customer-sited requirement TX: 5,880 MW by 2015 UT: 20% by 2025* ☼ CO: 20% by 2020 (IOUs) 10% by 2020 (co-ops & large munis)* MT: 15% by 2015 ND: 10% by 2015 SD: 10% by 2015 IA: 105 MW MN: 25% by 2025 (Xcel: 30% by 2020) ☼ MO: 15 % by 2021 WI : Varies by utility; 10% by 2015 goal MI: 10% + 1,100 MW by 2015* ☼ OH : 25% by 2025 † ME: 30% by 2000 New RE: 10% by 2017 ☼ NH: 23.8% by 2025 ☼ MA: 15% by 2020 + 1% annual increase (Class I Renewables) RI: 16% by 2020 CT: 23% by 2020 ☼ NY: 24% by 2013 ☼ NJ: 22.5% by 2021 ☼ PA: 18% by 2020 † ☼ MD: 20% by 2022 ☼ DE: 20% by 2019* ☼ DC: 20% by 2020 VA: 15% by 2025* ☼ NC : 12.5% by 2021 (IOUs) 10% by 2018 (co-ops & munis) VT: (1) RE meets any increase in retail sales by 2012; (2) 20% RE & CHP by 2017 29 states & DC have an RPS 6 states have goals KS: 20% by 2020 ☼ OR : 25% by 2025 (large utilities )* 5% - 10% by 2025 (smaller utilities) ☼ IL: 25% by 2025 WV: 25% by 2025* †

17. College of Engineering Background on Wind Energy in US Tax incentives Federal Incentives: Renewed incentives Feb 2009 through 12/31/12, via ARRA 2.1 cents per kilowatt-hour PTC or 30% investment tax credit (ITC) State incentives: IA: 1.5¢/kWhr for small wind, 1¢/kWhr for large wind Various other including sales & property tax reductions 17

18. College of Engineering Background on Wind Energy in US Climate bill 18 Waxman-Markey Energy & Climate Bill (House, passed) Kerry-Graham Climate Bill (Senate) 2012 renewables target6% of electric energy renewable In separate bill (Bingaman) 2020 renewables target20% 2012 Emissions targetCuts by 3% (2005 baseline) 2013 Emissions targetCuts by 4.25% (2005 baseline) 2020 Emissions targetCuts by 17% (2005 baseline)Cuts by 20% (2005 baseline) 2030 Emissions targetCuts by 42% (2005 baseline)42% (2005 baseline) 2050 Emissions targetCuts by 83% (2005 baseline)83% (2005 baseline) Emissions reductions are “economy wide” but there was interest to focus on utilities first, and perhaps only.

19. College of Engineering Background on Wind Energy in US 19

20. College of Engineering Solar, 0.09 Nuclear, 8.45 Hydro, 2.45 Wind, 0.51 Geotherma l0.35 Natural Gas 23.84 Coal 22.42 Biomass 3.88 Petroleum 37.13 26.33 8.58 27.39 20.9 Unused Energy (Losses) 57.07 Electric Generation 39.97 12.68 Used Energy 42.15 Residenti al 11.48 Commerci al 8.58 Industrial 23.94 Trans- portation 27.86 8.45 6.82 20.54 6.95 LightDuty: 17.12Q Freight: 7.55Q Aviation: 3.19Q 20

21. College of Engineering US ENERGY USE IS ABOUT 70% ELECTRIC & TRANSPORTATION US CO2 EMISSIONS* IS ABOUT 71% ELECTRIC & TRANSPORTATION GREENING ELECTRIC & ELECTRIFYING TRANSPORTATION SOLVES THE EMISSIONS PROBLEM 21 * Anthropogenic

22. College of Engineering Solar, 1.0 Nuclear,15 Hydro, 2.95 Wind, 8.1 Geothermal 3.04 Natural Gas 23.84 Old Coal 10.42 Biomass 3.88 Petroleum 15.13 26.33 8.58 24.5 8.5 Unused Energy (Losse s) 43.0 Electric Generation 49.72 12.68 Used Energy 42.15 Residenti al 11.48 Commerci al 8.58 Industrial 23.94 Trans- portation 15.5 15 6.82 20.54 6.9 5 INCREASE Non-GHG 12Q to 30Q USE 11Q Electric for transportation 4.5Q 22 IGCC, 2.26 REDUCE COAL 22Q TO 10Q REDUCE PETROLEUM 37Q  15Q LightDuty: 8.56Q Freight: 3.75Q Aviation: 3.19Q 22

23. College of Engineering 23

24. College of Engineering 24 Technolg y Forecasted NERC, 2018 Hi Eff&Renewable UCS (NEMS), 2030 Hi IGCC/CCS NAE, 2035 Hi Wind ISU, 2035 ∆GWOvernight cost Trillion $ ∆GWOvernight cost Trillion $ ∆GWOvernight cost Trillion $ ∆GWOvernight cost Trillion $ Con Solar 20.40.1022381.195-065.50.329 PV solar -01741.051-058.90.356 Nuclear 14.80.0494.40.0151000.33260.90.202 Wind onshore 2290.4406701.2883500.6736301.211 Wind offshore -0620.239-0800.307 Geothrml 0.4.00231.80.127-01060.424 Coal convntnl 190.039red0 0 0 IGCC+seq -070.0244001.40029.50.103 NGCC 1070.103-0-0-0 Biomass -01570.591-0-0 TOTALS 3890.73513444.5168502.40510312.930

25. College of Engineering Grand Challenge Question For Energy: What investments should be made, how much, when, and where, at the national level, over the next 40 years, to achieve a sustainable, low cost, and resilient energy & transportation system? 25

26. College of Engineering NUCLEAR GEOTHERMAL SOLAR Wind BIOMASS CLEAN-FOSSIL Where, when, how much of each, & how to interconnect?

27. College of Engineering Grand Challenges For Wind: 1.Move wind energy from where it is harvested to where it can be used 2.Develop economically- attractive methods to accommodate increased variability and uncertainty introduced by large wind penetrations in operating the grid. 3.Improve wind turbine/farm economics (decrease investment and maintenance costs, increase operating revenues). 4.Address potential concerns about local siting, including wildlife, aesthetics, and impact on agriculture. 27

28. College of Engineering Wind vs. people 28

29. College of Engineering How to address grand challenges 29 #1. Move wind energy from where it is harvested to where it can be used. Transmission Eastern interconnection Midwest to East coast National Superhighways at 765 kV AC and/or 600/800 kV DC Right of way (rail, interstate highwys, existing transmission) Cost allocation Organizational nightmare Conductor technologies: overhead/underground, materials Bulk storage

30. College of Engineering How to address grand challenges 30

31. College of Engineering How to address grand challenges 31 #2. Develop economically-attractive methods to accom- modate increased variability and uncertainty introduced by large wind penetrations in operating the grid. Variability: Increase gas turbines Wind turbine control Load control Storage (pumped hydro, compressed air, flywheels, batteries, others) Increase geodiversity Uncertainty: Decrease it: improve forecasting uncertainty Handle it better: Develop UC decisions that are more robust to wind pwr uncertainty

32. College of Engineering How to address grand challenges 32 #3. Improve wind turbine/farm economics (decrease investment/maint costs, increase operating revenues). Investment: Improve manufacturing/supply chain processes, construction, collection circuit layout, interconnection cost, land lease, and financing Operating & maintenance: Improve monitoring/evaluation for health assessment/prediction/life-ext Decrease maintenance costs (gearbox machines and direct-drive) Enhance energy extraction from wind per unit land area Improved turbine siting Inter-turbine and inter-farm control Increased efficiency of drive-train/generator/converters Lighter, stronger materials and improved control of rotor blades Taller turbines

33. College of Engineering 33 Wind turbine down-time distribution

34. College of Engineering How to address grand challenges 34 #4. Address potential concerns about local siting, including wildlife, visual/audible, impact on agriculture. Migratory birds and bats: mainly a siting issue for birds. Bat-kill is more frequent. Agriculture: Agronomists indicate wind turbines may help! Visual: a sociological issue These issues have not been significant yet. Today, in Iowa, there are ~2600 turbines, with capacity 3700 MW. At 2 MW/turbine, a growth to 60 GW would require 30000 turbines, and assuming turbines are located only on cropland having class 3 or better winds (about 1/6 of the state), this means these regions would see, on average, one turbine every 144 acres.

35. College of Engineering 1. What is a wind plant? Towers, Rotors, Gens, Blades 35 Manu- facturer CapacityHub HeightRotor Diameter Gen typeWeight (s-tons) NacelleRotorTower 0.5 MW50 m40 m Vestas0.85 MW44 m, 49 m, 55 m, 65 m, 74 m 52mDFIG/Asynch221045/50/60/75/95, wrt to hub hgt GE (1.5sle)1.5 MW61-100 m70.5-77 mDFIG5031 Vestas1.65 MW70,80 m82 mAsynch water cooled57(52)47 (43)138 (105/125) Vestas1.8-2.0 MW80m, 95,105m90mDFIG/ Asynch6838150/200/225 Enercon2.0 MW82 mSynchronous6643232 Gamesa (G90)2.0 MW67-100m89.6mDFIG6548.9153-286 Suzlon2.1 MW79m88 mAsynch Siemens (82-VS)2.3 MW70, 80 m101 mAsynch825482-282 Clipper2.5 MW80m89-100m4xPMSG113209 GE (2.5xl)2.5 MW75-100m100 mPMSG8552.4241 Vestas3.0 MW80, 105m90mDFIG/Asynch7041160/285 Acciona3.0 MW100-120m100-116mDFIG11866850/1150 GE (3.6sl)3.6 MWSite specific104 mDFIG18583 Siemens (107-vs)3.6 MW80-90m107mAsynch12595255 Gamesa4.5 MW128 m REpower (Suzlon)5.0 MW100–120 m Onshore 90–100 m Offshore 126 mDFIG/Asynch290120 Enercon6.0 MW135 m126 mElectrical excited SG3291762500 Clipper7.5 MW120m150m