Oct 27, 2007 Andrews, NC Brent Summerville, ASU Wind in WNC Oct 27, 2007 Andrews, NC Brent Summerville, ASU

NC Small Wind Initiative Appalachian State University Project to promote wind energy in Western NC Beech Mountain wind site Anemometer Loan Program Mapping Wind Site Assessments Workshops and Presentations Ordinance work Media Outreach Reach us at: wind.appstate.edu wind@appstate.edu 828-262-7333

Wind Power History 1400 – 1800 years ago, in the Middle East 800 – 900 years ago in Europe 140 years ago, water-pumping wind mills 70 years ago, electric power 1) Wind power has been an important energy source for at least 1400 years. (Some sources say 3,000 to 4,000 years.) 2) Crusaders brought the concept back to northern Europe where is it evolved into the European or “Dutch” windmill. 3) The American water-pumping windmill was an important innovation. It automatically tracked the changing wind direction and protected itself in high winds... the first wind machines to operate unattended. They were an important contributor to the settlement of the Great Plains. Over 6 million windmills have been sold… and counting! 4) Early in last century, electric utilities served only the cities. Beginning in the 1930’s, thousands of farms in the Great Plains generated their own electricity with small “wind chargers.” Federally-financed rural electric coops brought an end to this industry in the 1950s.

2MW Mod-1 Turbine: 1979 - 1983

1980s California Wind Rush

1980s Denmark Got it Right

Today: Wind Energy is Reliable and Cost Effective Wind has become the least expensive and fastest growing source of electricity in the world -details at www.gwec.net

Mountain Ridge Protection Act of 1983 “No building, structure or unit shall protrude at its uppermost point above the crest of the ridge by more than 35’ “ Exemptions to Ridge Law Water, radio, telephone or television towers or any equipment for the transmission of electricity or communications or both. Structures of a relatively slender nature and minor vertical projections of a parent building, including chimneys, flagpoles, flues, spires, steeples, belfries, cupolas, antennas, poles, wires, or windmills The Ridge Law was written during the time of the MOD-1experiment on Howard’s Know, a collaborative project by NASA and BREMO, the local electric cooperative. Several of the authors of the Ridge Law were representatives of Watauga County at that time. The meaning of the term “wind mill” has changed today, as the word “wind turbine” was not widely used in 1980. Developers and landowners in the mountain region have hesitated installing small and large wind due to the ambiguity of this situation. NC Attorney General’s 2/4/2002 letter to TVA “The Legislature in 1983 had in mind, the traditional, solitary farm windmill which has long been in use in rural communities, not windfarm turbines of the size, type, or certainly number proposed here…”

Our Wind Resource

Like most things, wind is powered by the Sun

What causes wind? Differences in pressure and temperature Solar Power Uneven heating of the Earth’s surface Differences in heating and cooling rates Earth’s rotation

Flagging: Deformed Growth from Persistent Winds

Extreme Flagging on Grandfather

Wind Maps

Updated Hi-res Map One of the powerful features of WinDS is easy access to the best wind resource data via the NREL GIS team and Donna Heimiller Note that no offshore resources are included for the southeast nor the Gulf of Mexico at this time. Note that currently WinDS uses annual average wind speed data but is capable of using seasonal/diurnal data

Location and Percentage of High Quality Wind Resources in the US Class 6 (4.3%) Class 5 (6.3%) Class 4 & above 27.5%

Average Wind Speed is the Key Most important variable Power ~ V3 Double speed and power increases 8 times 73% more power in a 12 mph wind than a 10 mph wind This is why it is so important to carefully assess

Western NC Wind Potential

New Hi-Res North Carolina Wind Map

We are not in South Dakota Careful site analysis is important The return button will take you back to the menu slide for this file.

North Carolina Coastal Resources

24 County Western NC Wind Map

County Wind Maps for Western NC True Wind Map Combined With: Road data Digital elevation models Public lands Appalachian Trail Town boundaries Utility grid Tax parcel maps www.wind.appstate.edu

What Fir Tree Farm - Watauga

Hattie Hill Site - Watauga

Wind Monitoring Activities Actual on-site measurements

Measuring Devices and Parameters Anemometer Best indication of energy production Indicator of turbulence Provide information on wind shear Wind Vane Wind rose Micro siting Temp Sensor Identify icing events Air density Data Loggers

TVA Monitoring Activities 50 meter met tower

Anemometer Loan Program

Measured vs Truewind Wind Speeds (m/s) (.23 m/s average difference)

Factors Affecting Wind Elevation Obstructions Surface Roughness Perpendicular Ridges Time of day Time of year

Elevation & Wind Velocity

Season and Time of Day Higher winds found late in the evening and early morning Higher winds seen during the winter

Wind Micrositing Where to put it

Step 1: What do you want to do?

Step 2: Resource Assessment Average annual wind speed at the proposed hub height is critical Wind maps Existing data Extrapolate wind speed from a lower height to hub height Measure Anemometer, wind vane, temp, logger Flagging, interview locals

Rule 1: Minimize Turbulence Rule 2: Minimum Tower Height “Micro-Siting” refers to how a wind turbine is placed on a given property. Trees and buildings are significant obstacles to the wind. We can’t see it, but the region of disturbed flow downwind of an obstacle is twice the height of that obstacle and quite long. For example, a 30-ft tall house creates a region of turbulence that is 60 ft high and 600 ft long (2 football fields!). This turbulence reduces power output from a wind turbine, and increases the stress and wear on that turbine. THE SOLUTION  Place the turbine upwind of obstacles (in the prevailing wind direction), or use a tower twice the height of the obstacles, or both. 30’ above obstructions within 300 – 500’

Tower Height Depends on Terrain

Rule 3: Stay upwind of obstacles Know the prevailing wind direction The turbine would like a clear view in that direction

5 10 15 20 25 30 35 N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW Wind Frequency Wind Speed Annual Frequency and Average Annual Wind Speed in Sixteen Compass Directions Potato Hill, Watauga County, NC

Rule 4: Minimize Compromises The wind blows from all directions There may not be the “perfect” spot The goal is to maximize your wind resource

Rule 5: Voltage and wire run Think about the wire run Higher voltage means smaller wire Raising the system voltage gives you more flexibility in tower placement

Visualizing the Turbulence Use a kite or balloon with streamers

Measuring Heights Shadow method

Measuring Heights Friend and Pen Tree Height

Micrositing Recap

Small Wind Turbine Technology

Small Wind Turbine Technology Horizontal Axis Upwind Horizontal Axis Downwind Vertical Axis Towers Systems

HAWT - Upwind Configuration: 2 or 3 blades aimed into the wind by the tail Blades: Fiber-reinforced plastics Over-Speed Protection: Furling (rotor turns out of the wind) Generator: Direct-drive, permanent magnet alternator (no brushes), 3-phase AC, variable-speed operation Bergey EXCEL, 10 kW

Southwest Windpower Flagstaff, Arizona www.windenergy.com Whisper 200 1000 W AIR 400 W Whisper 100 900 W Whisper 500 3 kW (Now with grid-tie)

Ned Trivette Whisper 200 Sugar Grove, NC

Beech Mountain Wind Energy Research & Demonstration Site

Bergey Windpower Norman, Oklahoma www.bergey.com BWC XL.1 1 kW BWC Excel 10 kW

Bergey 10kW Canton, NC

Abundant Renewable Energy Newberg, Oregon www.abundantre.com ARE110 2.5 kW

Homebuilt www.otherpower.com www.scoraigwind.com

Fuhrländer Lorax Energy Systems, Rhode Island www.lorax-energy.com FL 250 250 kW FL 100 100 kW FL 30 30 kW Fuhrländer is a German company. Lorax is the US company importing their products.

Over-Speed Protection During High Winds Furling: The rotor turns up and to one side, or back, or to the side

HAWT - Downwind wind Configuration: 2 or 3 blades, no tail, blades face downwind Blades: Fiber-reinforced plastics Over-Speed Protection: Zebedee Furl (blade coning), tip brakes, stall regulation Generator: Direct-drive, permanent magnet alternator (no brushes), 3-phase AC, variable-speed operation Proven WT600

Proven Engineering Products, Ltd. Scotland, United Kingdom. www Proven Engineering Products, Ltd. Scotland, United Kingdom www.provenenergy.com WT600 600 W WT2500 2.5 kW WT6000 6 kW Proven is a Scottish company. Several U.S. dealers are importing these turbines.

Proven Blade Coning Flexible Zebedee hinge As RPM increases, blades are thrown outwards by centrifugal force Changes aerodynamic pitch 10-15 year hinge life

Southwest Windpower Skystream 70 Foot Guyed Tower Southwest Windpower Skystream www.skystreamenergy.com

Southwest Windpower Skystream 35 Foot Monopole Tower Southwest Windpower Skystream www.skystreamenergy.com

VAWT – Drag & Lift Configuration: Lift or Drag Drag: Anemometer, Savonius Lift: Darrieus, H-Darrieus Anemometer Savonius Mother Earth News Darrieus

Savonius (S-rotor) Make from buckets, paddles, sails, and oil drums originated in Finland tsr ≈ 1 Can be useful for grinding grain, pumping water, and many other tasks …but are not good for generating electricity (low speed, high torque)

Darrieus Lift-Type Vertical-Axis Machines Darrieus, curved blades French engineer Georges Darrieus patented the design in 1931 Plus: generator on ground, yawing not required Minus: low to ground, low efficiency, not self-starting, vibration, high bearing forces H-Darrieus, straight blades

The main issue with VAWT: Availability on the Market

Small Wind Turbine Towers Fixed Guyed Tower Tilt-Up Tower Self-Supporting Tower

(3) guy wire anchors, climbing, crane Fixed Guyed Tower Build on ground Tilt-Up with crane (3) guy wire anchors, climbing, crane

Tilt-Up Guyed Tower Build on ground Tilt-Up with winch or grip-hoist (4) guys wire anchors, maintenance on ground, economical

Self Supporting Towers Build on ground Raise with crane No guy wires, requires climbing or crane

On-Grid Wind System without Storage Meter AC Inverter Wind turbine This simple schematic shows how a wind turbine is connected to the utility grid in a residential application. When wind-generated power exceeds the power consumption of the home, the excess power flows back to the utility. At other times, power flows from the utility to supplement the wind-generated power. The inverter delivers electricity at the same voltage and frequency as the utility grid. It also must turn off automatically if the utility grid goes down. When that happens, the home is without power. Load 02770329

On-Grid Wind System with Storage Meter Regulation and conversion AC Inverter Wind turbine In order to have backup power when the utility grid goes down, batteries must be used with the wind turbine. Energy previously stored in the batteries can be used to “ride through” a utility outage. (The inverter and home must disconnect from the utility grid during the outage. Some inverters can do this automatically.) This system has storage which provides backup power. Load 02770330

The Effect of Seasons on Hybrid Power Systems Summer PV modules and wind turbine Battery Loads (active generation) (storage) (utilization) (building on the previous slide:) The seasonal complimentarity of solar and wind resources provides a more continuous year-round energy supply in a hybrid system. Winter PV modules and wind turbine Battery Loads (no generation) (storage) (utilization) 02770322

Hours of sunshine or average wind power (Watts/m2) Solar and Wind Resources are Complimentary 400 Data from SE Iowa 350 Hours of sunshine/month Hours of Sunshine 300 Hours of sunshine or average wind power (Watts/m2) 250 It very important to understand how solar and wind resources vary during the seasons of the year. The trends shown in this chart of data from Iowa are representative of all the continental U.S.. The solar resource reaches a peak during the sunny summer months while the wind resource is highest in late winter to early spring. These resources are complimentary to one another during the year. (see following slide also) 200 Average wind power 150 100 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 02770324

PV/Wind Hybrid Project Installed on Beech

Energy

Power Power: Rate at which energy is delivered Power = Energy Time Measured in Watts (W), kilowatts (kW), or horsepower Power is an instantaneous quantity Power does not accumulate Think gallons per minute

Energy Energy: Ability to do something Measured in kilowatt  Hours (kWhrs) Why? Since Power = Energy/Time, then Power  Time = Energy Energy does accumulates over time Think gallons Gallons = (gallons/min)  minutes

Swept Area The single most important parameter of a wind turbine is its rotor’s swept area A

Power of a Wind Turbine The power of a wind turbine is P = ½  v3 A CP A: swept area of rotor CP: rotor efficiency Example: A 2.5 m diameter turbine with a 25% efficient rotor in our 8.0 m/s wind will have P = ½ (1.0 kg/m3)(8.0 m/s)3 [ (2.5 m/2)2](0.25) = 314 W

Method of Bins There are limitations to this method… Wind speed is not constant! Rotor efficiency depends on wind speed! Small turbines furl in high winds Here’s a better method: Method of Bins Need to know (or approximate) your wind distribution Power Curve of turbine

Wind Distribution Wind is known to follow a distribution pattern Credit: Paul Gipe

Power Curve The turbine’s manufacturer will provide you with its power curve Bergey XL.1

Method of Bins Calculate Energy = Power  Time for each wind speed bin Sum ‘um up!

Method of Bins Power Curve Wind Distribution (data) Annual Energy Output

Power Curve Southwest Windpower Whisper 100 and Whisper 200 Similar rated power Difference in energy

Charts from Manufacturer

Incentives

North Carolina Incentive Programs TVA Green Power Switch NC GreenPower NC Personal Renewable Energy Tax Credit NC Corporate Renewable Energy Tax Credit Green tags Renewable Energy Equipment Manufacturers Incentive Energy Improvement Loan Program USDA Farm Bill www.dsireusa.org

Green Tags

TVA Green Power Switch Generation Partners Program Details Wind or PV (.5 – 50 KW) Residential or small commercial $.15/kWh credit Energy used on site is billed at standard rate www.tva.com/greenpowerswitch/partners/index.htm

NC GreenPower Program www.ncgreenpower.org To improve the quality of the environment by encouraging the development of renewable energy resources through consumers’ voluntary purchase of green power. RFP process for green power No wind producers yet Green Power program initially quoted an estimate of .06/kwh

NC Net Metering Credited to a customer's next monthly bill, but reset to zero at the beginning of each summer (June 1) and winter (October 1) billing season. Any renewable-energy credits associated with net excess is granted to the utility when the balance is zeroed out. 20 kW for residential systems; 100 kW for non-residential systems Investor-owned utilities (Progress Energy, Duke Power, Dominion North Carolina Power) Photovoltaics, Landfill Gas, Wind, Biomass, Anaerobic Digestion

NC Renewable Energy Tax Credits 35% for all technologies Can take tax credit over 5 years No more than half of tax liability No refund based on tax credit To simplify and modernize the North Carolina tax credits for solar and other renewable energy sources, new legislation was enacted in the 1999 legislative session. Fourteen different credits were eliminated and replaced by one general credit that covered residential and non-residential solar and other renewable energy property. A credit of 35% was established for all renewable energy sources, with the maximum limits varying by renewable energy resource or technology, and by residential or non-residential sectors.

Wind Turbine Installed Cost Example This table is a summary of installed cost for a Bergey 10 kW turbine. The columns on the right show how costs can vary. Tower cost varies widely depending on the tower type and its height. Installation costs may be low for a do-it-yourself installation, or higher for a professional installation. Permits/Fees and Sales Tax can also vary over a large range. Notice that the costs can range from $30,000 to $60,000 (unit costs of $3,000 to $6,000/kW). Tax Credit $2,633 $3,511 $1,790 Final Cost $4890 $6,522 $3,325

USDA Farm Bill Section 9006 Farmers and Rural Small Business Owners Can Apply for: 25% from $2,500 to $500,000 Or up to $10 million in guaranteed loans Contact H. Rossie Bullock Business Programs Specialist 440C Caton Rd. P.O. Box 7426 Lumberton, NC 28359-7426 Phone: (910) 739-3349 ext. 4 Fax: (910) 618-9444 email: rossie.bullock@nc.usda.gov

Wind Turbine Installed Cost This table is a summary of installed cost for a Bergey 10 kW turbine. The columns on the right show how costs can vary. Tower cost varies widely depending on the tower type and its height. Installation costs may be low for a do-it-yourself installation, or higher for a professional installation. Permits/Fees and Sales Tax can also vary over a large range. Notice that the costs can range from $30,000 to $60,000 (unit costs of $3,000 to $6,000/kW). USDA Grant $11,389 $18,068 $8,702 Adjusted Total $34,167 $54,204 $26,108

This chart shows simple payback for a small wind turbine, that is how many years of utility bill savings are needed to recover the initial cost. Payback varies with many factors including wind speed, tower height, utility rates, turbine cost, and financial incentives. In particular, this chart illustrates how a 50% buydown incentive can significantly reduce wind system payback.

Questions? Thanks Brent Summerville Call or email me for more info 828-262-7333 wind@appstate.edu wind.appstate.edu My presentations will be available at wind.appstate.edu Click on REPORTS….CONFERENCE PRESENTATIONS