HISTORY125 - Wind and its Power

I owe Pat another one.  “Wind” came up in a recent discussion of potential blog topics and I immediately picked up on it. 

After a short introduction, I will discuss the effects of wind, what causes wind, and how wind has affected our culture, before focusing on the history of wind power.   I will conclude with some interesting facts about wind and wind power.                                  

As usual, I will list my principal sources at the end.

 

Introduction

Wind is the movement of atmospheric air from high-pressure areas to low-pressure areas, which we feel as wind.  The greater the difference in pressure between two areas (the pressure gradient), the faster the wind will blow.

Wind can be a gentle breeze or a powerful storm-force gust, depending on the pressure differences involved. Examples and types of wind include:

·         Breeze: A gentle wind.

·         Gale: A wind between 32 and 63 miles per hour (mph).

·         Squall: A strong wind that lasts for about a minute.

·         Gust: A short, fast burst of wind.

·         Trade Winds: Steady winds that flow toward the equator.

·         Jet Streams: Powerful winds that blow at high altitudes.

·         Other types: Strong winds have many names, including hurricanes, tornadoes, and typhoons. 

The study of wind is called anemology.  Wind is measured with an anemometer for speed and a wind vane for direction.  The most common type of anemometer has cups that spin when wind blows. The faster the wind, the faster the cups spin, and this rotation is used to calculate wind speed.  A wind vane has a pointer that turns freely on a spindle, and indicates the direction from which the wind is blowing.  For example, a wind vane pointing east indicates an easterly wind (a wind blowing from the east).  Anemometers and wind vanes are standard tools for meteorologists, pilots, and engineers.

Typical anemometer and wind vane assembly.

 

The Effects of Wind

Winds can shape landforms, via erosion, transport, and deposition of sediments.  Dust from large deserts can be moved great distances from its source region by prevailing winds that consistently blow from a single general direction.  Wind also affects the spread of wildfires.  Winds can disperse seeds from various plants, enabling the survival and dispersal of those plant species, as well as flying insect and bird populations.  Wind drives surface currents in the ocean. 

Wind affects weather by transporting heat, moisture, and pollutants, which influence temperature, humidity, and precipitation.  Wind moves warm air from the equator toward the poles and cold air in the opposite direction, regulating global climate.  It also transports moisture, influencing humidity levels.  By distributing water vapor, wind plays a key role in determining precipitation patterns.  Strong winds can clear stagnant air, dispersing pollutants, but light winds can trap and concentrate them.  Wind interacts with topography like mountains to create distinct cloud formations. 

High winds can cause significant damage, including tearing off roofs, uprooting trees, and damaging buildings and power lines, which can lead to power outages.  Wind can disrupt transportation, especially maritime activities, and impact essential services.  Here in Arizona and New Mexico, wind can blow dust into the air from barren land near highways, and produce “whiteouts,” that are a significant cause of accidents for unwary drivers.

Wind chill from high winds can affect human and animal comfort by making cold temperatures feel colder.  Conversely, wind can provide a cooling breeze in hot weather.  Wind, particularly during high-wind events, can damage animal habitats and disrupt natural processes, such as fish migration routes.  Wind turbines can pose a collision risk to birds and bats.

Wind can even provide opportunities for recreation, including fly kites, flying in hot air balloons, and soaring wind currents in gliders.

Wind has always played an important role in human culture and history, and since ancient times it has been the subject of myths and legends, often associated with gods and spirits. 

Wind provides energy to produce mechanical and electrical power.  The history of wind power dates back thousands of years, evolving from ancient sailboats and windmills for grinding grain to modern, utility-scale wind turbines that generate electricity for millions of homes. 

 

What Causes Wind

Wind is caused from the Sun's uneven heating of the Earth, which creates differences in air pressure.  The Sun heats the Earth's surface, but not uniformly.  For example, land heats up faster than water.  This uneven heating causes the air above warmer areas to heat up, expand, and rise. This creates a low-pressure zone.  Cooler air is denser, sinks, and creates a high-pressure zone.  Air naturally flows from areas of high pressure to areas of low pressure to balance the difference. This movement of air is wind.  The greater the difference in air pressure, the stronger the wind will be.

 

There are several other factors that influence wind.  The Earth's rotation affects large-scale, global wind patterns.  Near the Earth's surface, friction between the Earth and atmosphere causes the wind to be slower than it would be otherwise.  Earth’s irregular surface, including mountains and valleys, affects wind speed and can channel winds, intensifying them in certain areas like mountain passes.  The daily cycle of land heating and cooling creates local winds, like sea and land breezes.  Seasonal heating differences drive larger weather patterns. 

Globally, the two major driving factors of large-scale wind patterns are the differential heating between the equator and the poles (difference in absorption of solar energy) and the rotation of the planet.  Outside the tropics and aloft from frictional effects of the surface, the large-scale winds tend to approach equilibrium where the force from the rotation of the Earth and the pressure gradient force are perfectly balanced, resulting in a steady flow of wind. 

 

Wind in our Culture

Many ancient civilizations saw wind as a divine force, associating it with gods and spirits.  The Sumerians identified the wind with Enlil, the ancient Mesopotamian God of Wind and Storms, while in ancient Egypt, Shu personified the air and the wind.

The ancient Greeks venerated Aeolus, the God of the Wind, who had the power to evoke and appease the winds and control storms.  He was considered one of the twelve great Olympus Gods.  In Greek culture, the winds were also associated with several other minor deities, including Zephyr and Noto.  In Greek mythology winds were also associated with events, places, and people such as the God of the North Wind, Boreas, associated with storm and cold.

Wind was also connected to concepts like breath, life, and the afterlife.  In some African and South American myths, the wind deity is associated with change and rebirth.  The Navajo connected wind with guidance, strength, and the movement of life force.  At times, wind was viewed with fear, seen as a destructive force that could cause illness or death, a belief that persisted in parts of Europe into the early modern period.  Wind-related deities were considered responsible for storms and changes in the weather, and their cult was closely linked to agricultural work and navigation.

In popular culture, the wind was also seen as an omen of future events. 

The wind has also been a source of inspiration for literature, poems, and films.  In literature, the wind has been described as a symbol of strength and freedom, but also of change and uncertainty.  In many poems, the wind has been described as a wild and uncontrollable force, as well as a beneficial force that cleanses the air and brings freshness.  In romantic poetry, the gentle "zephyr" or west wind is a recurring motif for the fleeting nature of love and happiness.  In cinematography, the wind has been used as a metaphor to represent the uncertainty and uncontrollability of life.  Films have used the wind as a symbol of change and struggle.

Wind chimes in various cultures are used to attract good fortune or ward off evil spirits. 

The wind has also been used in many phrases and idioms, such as “the wind turns” and “the wind changes” - which represent the uncertainty and changeability of life.  Furthermore, the wind has been described in many proverbs and idioms, such as “The wind blows where it wants” which represents the unpredictability and uncontrollability of the wind and of life, or “the wind is capricious” which represents its tendency to change.

Wind is also used to today to provide spiritual guidance; see the example below:

 

The History of Wind Power

The history of wind power spans millennia, starting with harnessing wind for propelling sailboats in ancient Egypt around 3500 BC. and the use of windmills for grinding grain and pumping water in Persia between 500 and 900 BC.  The technology spread to Europe, where windmills were adapted for tasks like draining land in the Netherlands, and later to America for farming and ranching.  The transition to wind-generated electricity began in the late 19^th century, with the first large-scale electric turbine installed in Vermont in 1941, and a major revival of interest in wind power occurred in the 1970s due to oil shortages.  

Here are some milestones in the development of wind power:

Antiquity: In 5000 BC the Egyptians used lightweight, long, and thin boats for fishing and short trips on the Nile.  The boats were made of papyrus reeds and propelled by rowers using oars.  By as early as 3500 BC, the Egyptians were using sails made from animal skin or woven material to catch the wind, a significant improvement.  By about 2900 BC, the Egyptians were using wooden sailboats made of acacia and cedar wood.  This enabled exploration, trade, and the discovery of new lands.

Model of early Egyptian sailboat.

The first practical windmills were developed in Persia (modern-day Iran) between 500 and 900 BC. They were used for grinding grain and pumping water.  Persian windmills had vertical blades attached to a central axis.  The wind would turn the blades, and the rotational energy would be used to drive various mechanical devices, such as water pumps, grain mills, and irrigation systems.   This made it particularly useful in regions like Persia, where large-scale agriculture and irrigation were essential for sustaining life in arid environments.

Early Persian windmill.

In 200 BC, China began using simple, wind-powered water pumps. 

The Middle Ages and Early Modern Period:  In the 11^th century AD, windmills were introduced to Europe from the Middle East, where they became widespread for grinding grain and pumping water.  The earliest known windmill in the United Kingdom was built in 1185. 

In the 14^th century, the Dutch adapted windmills for large-scale water management to drain lakes and marshes in the Rhine River Delta. 

In the 16^th - 19^th centuries, Europeans introduced windmill technology to the Americas, where colonists and pioneers used thousands of windmills to grind grain, pump water, and power sawmills. 

 

Typical windmill in 1800s America.

Transition to Electricity (late 19^th Century): In 1887, Scottish Professor James Blyth built the first wind turbine to generate electricity, using it to power the lighting in his holiday cottage.  The local community, however, initially rejected the offer of excess power, believing it to be "the work of the devil.”

The first wind turbine to generate electricity.

In 1888, American inventor Charles F. Brush built a large, 12-kilowatt wind turbine to power his estate in Cleveland, Ohio.  It operated for 12 years before central station electricity became widely available.

Charles Brush wind turbine.

In 1891, Danish scientist Poul la Cour developed more efficient turbines with fewer blades, using the generated electricity for electrolysis to produce hydrogen for lighting.

In the 1930s, before widespread rural electrification, many American farms used small, wind-powered generators to charge batteries.  This usage declined significantly after government programs extended power lines to rural areas. 

In 1941, the world's largest wind turbine at the time, a 1.25-megawatt turbine on "Grandpa's Knob" in Vermont, was connected to a local utility network. 

The development of steel blades in the 20^th century, and interest in renewable energy led to the modern wind turbines used to generate electricity today. 

Modern wind turbine.

 

Modern Era: From Crisis to Innovation: In the 1970s, the dramatic rise in oil prices spurred interest in renewable energy sources, including wind power.  Research programs, including one by NASA, were established to develop larger, utility-scale turbines.

In 1978, the U.S. passed the Public Utility Regulatory Policies Act, which required utility companies to purchase a fixed amount of electricity from renewable sources, boosting the development of larger commercial turbines. 

In 1980, the world's first wind farm, consisting of 20 wind turbines, each with a 30-kilowatt maximum electrical power output (capacity) was installed on Crotched Mountain in New Hampshire.

A wind farm is a collection of wind turbines (up to several hundred) in the same location that work together to produce electricity. The turbines convert the kinetic energy from moving air into electrical power. There are two main types of wind farms: onshore (on land) and offshore (in large bodies of water).  Wind farms are typically erected in areas where there is a nearly steady prevalent wind, like open plains, hilltops, and coastal regions to maximize energy capture.

Alta Wind Energy Center is the third largest onshore wind farm in the world, located in Tehachapi Pass of the Tehachapi Mountains, in Kern County, California.

In 1991, the world's first offshore wind farm, Vindeby, was built in Denmark.

The 2000s saw a rapid expansion of the wind power industry, driven by growing environmental concerns and dropping costs.  Innovations like floating wind turbine technology, which allows for installation in deep offshore waters, continue to push the industry forward. 

Today, wind energy is a booming global industry, with China leading in installed capacity, followed by the United States.  Wind power is a major source of renewable energy, with continuous growth in both onshore and offshore capacity. Ongoing technological advancements focus on building taller, more powerful turbines to capture stronger, more consistent winds at higher altitudes. 

 

Interesting Facts about Wind and Wind Power

1.       The strongest wind ever recorded was on April 10,1996 during tropical cyclone Olivia in Australia, with a gust of 253 mph.

2.       Mount Washington in New Hampshire is known for having some of the most extreme and consistently high winds in the world. The average wind speed year-round is 35 mph, and winds regularly exceed hurricane force (75 mph), especially during winter.  The highest wind gust ever recorded there was 231 mph.

3.       Today’s wind turbines are much more complicated machines than the traditional prairie windmill.  A wind turbine has as many as 8,000 different components.

4.       Wind turbines are big.  Wind turbine blades average 210 feet long, and turbine towers average over 320 feet tall - taller than the Statue of Liberty.

5.       Wind turbines are extremely quiet.  A wind turbine produces about the same amount of noise you’d hear from a refrigerator at 150 feet, making it virtually undetectable.

6.       One wind turbine can produce enough electricity to light up almost 600 homes!

7.       The Gansu Wind Farm in China is the world's largest onshore wind farm, with a planned capacity of 20 gigawatts, currently at an operational capacity of 10 gigawatts as of June 2021.  When it’s complete, the Chinese wind farm will feature 7,000 wind turbines.

8.       The larges offshore wind farm in the world, the Dogger Bank Wind Farm in the U.K., will have a capacity of 3.6 gigawatts when fully operational.

9.       China and the U.S. are the world’s biggest producers of wind energy.

10.   Although it’s the largest emitter of greenhouse gases, China also produces the most wind energy in the world - around 60% of all wind energy worldwide.

11.   The United States has the second most installed capacity of wind turbines in the world.  Since 2020, the United States has installed more than 45 gigawatts of wind capacity, bringing the cumulative total to more than 150 gigawatts, enough to power around 45 million homes. 

12.   Wind energy in the U.S. provides more than 20% of total electricity generation in 12 states, with more than 50% in Iowa and South Dakota, and more than 40% in Kansas and Oklahoma.  Overall, wind energy supplied more than 10% of total U.S. electricity generation in 2023.

13.   Many of the components of wind turbines installed in the United States are manufactured here, with more than 450 wind-related manufacturing facilities across the country.  The U.S. wind industry currently employs more than 125,000 full-time workers.

14.   Prices for wind power contracts signed in the last few years have ranged from 1.4 - 5.5 cents per kilowatt-hour, with an average of 2.5 cents per kilowatt-hour. 

15.   In order to generate enough electricity to power the entire Earth, we would need to build nearly 4 million turbines!  As of today, there are over 341,000 wind turbines on the planet, spread across 83 countries.  While governments around the world have ramped up efforts in recent years to scale up wind power, we are still far from being able to power the whole world using wind energy.

Conclusions

The case for wind power rests on its environmental benefits, economic advantages, and growing potential as a cost-effective, renewable energy source.  Wind power is emissions-free during operation, can be installed in diverse locations, and creates jobs and revenue for local communities.  As technology advances and costs decrease, wind energy, both onshore and offshore, is poised for significant expansion as a key part of the global energy transition. 

 

 

As yet, the wind is an untamed, and unharnessed force; and quite possibly one of the greatest discoveries hereafter to be made, will be the taming, and harnessing, of the wind. - Abraham Lincoln

 

 

Sources

My principal sources include: “Wind” and “History of Wind Power,” Wikipedia.com; “How is wind formed?” enelgreenpower.com; “The Wind in Culture and History,” enessere.com; “A Brief History of Wind Power,” nesfircroft.com; “Top 10 Things You Didn’t Know About Wind Power,” energy.gov; plus, numerous other online sources, including answers to many queries using Google in AI Mode.