Wind Farms 101
Gary Snyder, RES, Oklahoma State University
Wade Patterson, Garfield County Assessor
What is wind energy and how
is it generated?
Wind energy is a source of renewable energy that
harnesses the kinetic energy of the wind or, in other
words, of the air in movement.
Once transformed to mechanical energy, wind energy
can be used for various applications (windmills to
pump water or grind cereals).
The most common use nowadays is to generate electricity
using wind turbines.
Picture of
new and old
“wind mills”
How do wind turbines work?
The wind’s kinetic energy is transformed into electricity
by wind turbines.
These are made up of a tower, a gondola comprising a
rotor and an anemometer (measures wind speed), a
weather vane or “weathercock” to indicate wind
directions and a lightning conductor.
Wind turbine diagram expanded
Source: Way2Science
How do wind turbines work?
A Rotor is composed of the blades and an axle,
attached to each other by a bearing, this allows for
the pitch of the blade to be adjusted.
The blades, moved by the wind, transmit force to the
low speed shaft, which is connected to a multiplier
(gearbox) that increases the axle speed.
The mechanical energy is transferred from the
multiplier to an electricity generator, which
transforms it into electricity for subsequent injection
into the grid.
Source: AWEA
Basic diagram of a wind turbine
How do wind turbines work?
The range of wind turbine power goes from 100 W
with a blade diameter of around 1 meter, which
are mainly used for residential purposes, to about
5 MW (5,000,000 watts) with a blade diameter
and tower height greater than 100 meters.
400 Watt Turbine
600 Watt Turbine
One 1.6 MW turbine will provide
enough power for 500 typical homes
1.8 Megawatt Turbine,
or the equivalent of
4,500 small 400 Watt
turbines
Definitions
• Renewable Energy - Energy derived from resources that are
regenerative or that cannot be depleted. Types of
renewable energy resources include wind, solar, biomass,
geothermal, and moving water.
• Grid (also “Power Grid” and “Utility Grid”) - A common
term referring to an electricity transmission and distribution
system.
• Wind Turbine - A term used for a wind energy conversion
device that produces electricity.
Definitions
• Generator - A device for converting mechanical energy to
electrical energy.
• Met Tower - Meteorological towers erected to verify the
wind resource found within a certain area of land.
• Nacelle - The cover for the gearbox, drive train, and
generator of a wind turbine.
• Rotor - The blades and other rotating components of a
wind energy conversion turbine .
Definitions
• Watt (W) - The rate of energy transfer (from an outlet to
an appliance, for example). Wattage is calculated by
multiplying voltage by current.
• Kilowatt (kW) - A standard unit of electrical power equal
to 1,000 watts.
• Megawatt (MW) - The standard measure of electric power
plant generating capacity. One megawatt is equal to one
thousand kilowatts or 1 million watts.
• Gigawatt (GW) - A unit of power equal to 1 million
kilowatts.
Definitions
• Capacity Factor - The amount of power a turbine actually
produces over a period of time divided by the amount of power it
could have produced if it had run at its full rated capacity over that
time period.
• Specific Yield - Measurement of the annual energy output per
square meter of area swept by the turbine blades as they rotate.
• Rated Power Output - Used by wind generator manufacturers to
provide a baseline for measuring performance. Rated output may
vary by manufacturer.
• Rated Wind Speed - The wind speed at which the turbine is
producing its nameplate-rated power production. For most small
wind turbines this is around 30 to 35 miles per hour.
Definitions
• Start-Up - The wind speed at which a wind turbine rotor
starts to rotate. It does not necessarily produce any power
until it reaches cut-in speed.
• Cut-In-Speed - The rotational speed at which an alternator
or generator starts pushing electricity hard enough (has a
high enough voltage) to make electricity flow in a circuit.
• Cut-Out Speed - The wind speed at which the turbine
automatically stops the blades from turning and rotates
out of the wind to avoid damage to the turbine.
Definitions
• Power curve - The instantaneous power output of a specific
turbine design at various wind speeds. Used with wind
resource data to determine the potential for electricity
generation at a project site.
• Furling - The act of a wind generator Yawing out of the wind
either horizontally or vertically to protect itself from high
wind speeds.
• Yaw - Rotation parallel to the ground. A wind generator
Yaws to face winds coming from different directions.
Wind farms
It is normal practice, to group wind turbines together
within wind farms to harness the maximum wind
force and obtain greater quantities of energy.
The turbines are separated from each other in these
parks by a minimum distance of three times the
diameter of the rotor and a maximum of nine times
this diameter, in order to avoid wind turbulence and
make it easier to connect the wind turbines to the
electricity grid.
Wind turbine turbulence
Wind farms
When evaluating a potential wind farm site, the ground
conditions have to be taken into account, such as
unevenness, the existence of obstacles and the
area's orography (the study of the formation and
relief of mountains), so that the best return possible
is achieved.
Uneven ground reduces wind speed, while obstacles
such as trees, buildings, and outcrops cause
turbulence, which has a negative effect on the wind
harnessed for electricity generation. These factors
also cause wind turbines to wear faster.
Wind farms
Making good use of an area’s orography can have
advantages and result in improved performance.
Thus, a good option is to position turbines in “tunnels”
between, for example, two rock outcrops, where the
wind speed is greater.
Wind farms are also frequently installed on hilltops
since the wind speed is greater at higher altitudes.
Wind turbines at Blue Canyon Wind Farm, SW Oklahoma
Wind turbines at Blue Canyon Wind Farm, SW Oklahoma
The Production Tax Credit (PTC)
--American wind power's key federal incentive (the 2.2 cents
per kilowatt-hour Production Tax Credit, or PTC) only applies
to projects that succeed in putting electricity on the grid. It
will expire Dec. 31, 2012, unless Congress extends it.
--The PTC has not been allowed to expire since 2005, when
President George W. Bush extended it as part of the Energy
Policy Act.
--This successful policy over the past several years has
incentivized $15.5 billion a year on average in private
investment in the United States. Wind facilities account for
35% of all new energy production capacity (measured in
megawatts) in the United States. This is a close second to
natural gas.
Source: AWEA
The Production Tax Credit (PTC)
The PTC, the main policy tool in the deployment of U.S.
wind power, was first adopted during the administration
of President George H.W. Bush as part of the Energy
Policy Act of 1992 (P.L. 102-486).
It has been a significant driver of the recent growth of the
U.S. wind industry. In each of the years during which the
PTC lapsed (2000, 2002, and 2004), meaning that it
expired prior to being renewed, the level of additional
deployed wind capacity slowed or collapsed when
compared to the previous year’s total: 93% in 2000, 73%
in 2002, and 77% in 2004
History of new wind production capacity in
relation to the Production Tax Credit (AWEA)
The wind energy Production Tax Credit
Congress provided a three-year extension of the PTC
through December 31, 2012, as part of the American
Recovery and Reinvestment Act.
The PTC provides an inflation-adjusted per kilowatt-hour
(kWh) income tax benefit over the first ten years of a wind
project’s operations, which in 2010 was 2.2 cents per kWh,
and is a critical factor in financing new wind farms.
In order to qualify, a wind farm must be completed and start
generating power while the credit is in place, which would
be by the end of 2012.
National Renewable Energy Laboratory
Innovation for Our Energy Future
Notice the huge increase in wind production from the slide showing 1999 production!
How a wind farm is developed
Find a windy site. Look for sites where the average
wind speed is appropriate for the turbines to be
used.
Make sure the site has nearby transmission lines.
It’s not enough to find wind. There has to be a way
to transport the electricity generated by a wind
farm to a main power grid.
Define the boundaries. After you find a windy place
that’s near a power grid, define the boundaries of
the prospect area.
(North American Electric Reliability Corporation)
Northeast Power Coordinating Council
Midwest Reliability Organization
Reliability First Corporation
Western Electricity Coordinating Council
Southwest Power Pool
SERC Reliability Corporation
ERCOT
Electric Reliability Council of Texas
Florida Reliability Coordinating Council
By: TheWINDCOALITION
How a wind farm is developed
Determine who owns the land within the prospect
boundaries. The owners of the land within the prospect
boundaries are potential partners.
Contact the landowners. In order to gauge interest in wind
farm development, the wind energy company contacts the
landowners about the possibility of a partnership.
Call a town meeting. If there are many landowners in the
same area, a town meeting helps explain the ins and outs
of wind farm royalty payments and natural resource
management.
How a wind farm is developed
Settle the contracts. A company and the landowners will
negotiate agreements for test towers and options for
lease agreements.
Create blueprints. The company lays out potential wind
farm configurations to give landowners an idea of where
the turbines might be placed.
Watch the wind. A company typically monitors the wind
for 6 months to 2 years to corroborate their data with
publicly available wind data.
How a wind farm is developed
Get the necessary permits. While testing the wind’s
power, the company is also acquiring the necessary
permits at the federal, state, and county levels.
Perform environmental analyses. The company is
required to ensure the safety of local wildlife and the
environment.
Test the wires. Testing grid connections is very
important. Companies will perform additional
transmission research.
How a wind farm is developed
Sell the electricity. Selling wind generated
electricity is the “Holy Grail” in the business.
Most wind energy companies cannot build a
project until a customer is found.
Because of the huge upfront cost, projects are
feasible only after a customer, such as a large
utility, has committed to a long-term energy
purchase (power purchase agreement or PPA)
of 10 to 20 years in duration.
How a wind farm is developed
Begin construction. The construction phase usually
takes about 9 months to a year.
Work with landowners to minimize disturbance to
the land. The company will build roads and
erect turbines. The company will establish the
electrical and engineering work to connect the
turbines to the grid.
Wind turbines and access roads occupy less
than 3% of the land in a typical wind farm.
Electricity distribution diagram
What are the
components of a
wind farm?
Meteorological (Met)
tower
Met tower being constructed
80 meter met tower,
approximately 265’
Turbine base pad excavation
Turbine base sub-frame
Pouring concrete for the base
Installing conduit for lines
Completed tower base, ready for a tower
Tower lay down site
Installation of the
bottom section of the
tower
Installation of the
middle section of
the tower
Final adjustments
Second section
weight
Maneuvering the a
section of the tower
into place
Nerves of steel!
View from inside
the tower
Top 10 wind turbine manufacturers by annual
market share (installed capacity) in 2011 by IHS Inc.
Vestas
Sinovel
Goldwind
Gamesa
Enercon
GE Wind Energy
Suzlon Group
Guodian United Power
Siemens Wind Power
Ming Yang
Source;: Wikipedia
12.7%
9.0%
8.7%
8.0%
7.8%
7.7%
7.6%
7.4%
6.3%
3.6%
Nacelle and hub lay down site
Close-up of the nacelle
Starting to connect the nacelle and the hub
Connecting the nacelle and the hub
Final adjustments
before nacelle and hub
are connected
Easy does it!
Lifting the nacelle
into place
Lifting the nacelle to
the top of the tower
Nacelle installation
Attaching the nacelle
to the tower
Blade lay down yard
Blade being
transported to the
tower site
In-air blade installation
In-air blade installation
In-air blade final
attachment to the hub
Assembled blade and
hub being lifted into
place
Installed blade and hub
Tower base and
access door
Completed tower
Every tower will
have a
connection box
Trench for the
interconnect lines
Wind farm substation
Completed wind
turbine and pad site
Aerial view of a wind farm
Aerial view of a wind farm
View of the inside of the nacelle
Removing the “internal organs” of the nacelle
Picture of a
“climbing crane”
Image: © VESTAS WIND SYSTEMS A/S
Image: © VESTAS WIND SYSTEMS A/S
Chisholm View Wind Project
Project Location:
The Chisholm View Wind Project is located
approximately 15 miles North and East of Enid,
Oklahoma and directly adjacent to Hunter, OK. The
project sits within Garfield and Grant Counties.
Wind Power Classes
Wind Power
Class
10 meter
50 meter
Wind Power
density
Speed m/s
(mph)
Wind Power
Density
Wind Speed m/s
(mph)
1
0
0
0
0
2
100 - 150
4.4 (9.8) / 5.11
(11.5)
200 - 300
5.6 (12.5) / 6.4
(14.3)
3
150 - 200
5.1 (11.5) / 5.6
(12.5)
300 - 400
6.4 (14.3) / 7.0
(15.7)
4
200 - 250
5.6 (12.5) / 6.0
(13.4)
400 - 500
7.0 (15.7) / (16.8)
5
250 - 300
6.0 (13.4)/6.4
(14.3)
500 - 600
7.5 (16.8)/8.0
(17.9)
6
300 - 400
6.4 (14.3)/7.0
(15.7)
600 - 800
8.0 (17.9)/8.8
(19.7)
>8.8 (19.7)
7
>400
>7.0 (15.7)
>800
Wind rating for Oklahoma
Chisholm View
Chisholm View
Chisholm View Wind Farm, Garfield Co. OK
Close-up of Chisholm View
Chisholm View Wind Project
Project Interconnection:
An existing 345kv line owned by Oklahoma Gas &
Electric runs through the project site.
Chisholm View will interconnect directly onto this line
and have the ability to deliver energy South to load
centers such as Oklahoma City and North to load
centers in and around Wichita, KS.
Chisholm View Wind Project
Project Size:
235 MW (140 Turbines)
Project Turbines:
GE 1.6 MW
Landowners and Acreage Involved:
Chisholm View encompasses approximately 45,000
acres and involves over 150 landowners.
Chisholm View Wind Project
Utility Buyers:
The power produced by Chisholm View (located in the
SPP grid region) will be sold to Alabama Power
Company, a subsidiary of Atlanta-based Southern
Company. (located in the SERC grid region)
The Chisholm View Wind Project will deliver clean, low
cost electricity to communities in Alabama.
(North American Electric Reliability Corporation)
Northeast Power Coordinating Council
Midwest Reliability Organization
Reliability First Corporation
Western Electricity Coordinating Council
Southwest Power Pool
SERC Reliability Corporation
ERCOT
Electric Reliability Council of Texas
Florida Reliability Coordinating Council
By: TheWINDCOALITION
Chisholm View Wind Project
Key Project Attributes:
A 235 MW Chisholm View Wind Project would produce
enough power for approximately 80,000 Alabama homes.
The project will take only approximately 1-2 percent of land
out of service to build, including all land for roads, turbine
foundations, and maintenance buildings.
Chisholm View is one of the most energetic wind
development sites in North Central Oklahoma.
Chisholm View Wind Project
Key Project Attributes continued:
Once fully developed, Chisholm View Wind project will
contribute up to $5 million per year in total annual
landowner payments.
The project enjoys broad community support from
landowners and local government agencies.
The project is expected to have no material effect on any
threatened and endangered species of birds or animals
based on third party studies commissioned by TradeWind
Energy.
Road Maintenance Agreement Overview
“Primary Roads” are identified – i.e. major construction traffic
corridors
Designation of condition and/or type of road
Site plan is approved by county as part of agreement
County authorizes project’s use and improvement of said
roads
Counties waive weight restrictions in return for payment
and/or upgrade/repair obligations
Road Maintenance Agreement Overview
County to continue routine maintenance during construction
Project agrees to specific payments due and/or upgrade and
restoration obligations and specs
Culverts and bridges needing replacement or repair are identified
County allows Project to make routine improvements and initiate
routine maintenance of Primary roads at its own expense
County authorizes crane crossing of ROW, increasing radiuses
of intersections, etc
Permitting Requirements
Chisholm View Wind Project
Environmental Studies Completed
Avian Migration, Raptor Migration,
Raptor Nest, Bat Monitoring, Cultural
Resources, Wetlands, Threatened and
Endangered Species Habitat Assessment,
Phase I Environmental Site Assessment,
Microwave Beam Path, TV, AM/FM
Site Prospecting and Selection
Q1
2008
Interconnection Feasibility Request Filed (SPP)
Q1
2008
Assessor Supplied GIS Ownership
Q1
2008
Begin Contacting Landowners to Gauge Interest
Q1
2008
Met Tower Installation (1st of many)
Q1
2008
Initiate Land Leasing Campaign
Q2
2008
Conduct Town Hall Meetings (1st of many)
Q2
2008
Initial Field Environmental Surveys
Q1
2009
Continue Environmental Surveys, Wind Data Collection, Leasing, PR
all
2009
Initiate Power Marketing Efforts
2009
Land Leasing Substantially Complete
Q1
2010
Generator Interconnection Agreement Executed (SPP)
Q3
2010
Continue Environmental Surveys, Wind Data Collection, Leasing, PR
all
2010
Power Purchase Agreement Executed
Q3
2011
Initiate Permitting
Q3
2011
Initiate Final Engineering
Q3
2011
Procure Major Equipment
Q4
2011
Complete Road Maintenance Agreement w/ County
Q1
2012
Permitting Complete
Q1
2012
Construction Commencement
Q1
2012
Turbine Erection Begins
Q3
2012
Final Completion - Commercial Operation
Q4
2012
Construction Restoration Complete (roads, bridges, private)
Q1
2013
Wind Project Operations
Q1
2013 and on
Chisholm View
project time line of
events
The first completed
tower in the
Chisholm View
Wind Farm.
Picture taken July
27, 2012!
Sources
•
•
•
•
•
•
•
•
•
•
•
AWEA
EDP Renewable North America / Horizon Wind Energy
ENEL Green Power, North America
FEMA
Garfield County Commissioners
NREL
The WINDCOALITION
Trade Wind Energy
Vestas Wind Systems
Way2Science
Wikipedia
Questions?
gary.snyder@okstate.edu
lwade@garfieldcountyemail.com