CHAPTER 1
First Wind: Introduction to Small Wind Power

I can’t change the direction of the wind, but I can adjust my sails to always reach my destination.

–JIMMY DEAN

Regardless if this is your first project or your umpteenth project, you are charged up about harnessing your own wind (Figure 1-1). So let’s breeze through this first chapter.

FIGURE 1-1 A 10 kW small wind turbine on lattice tower at Windy Acres Farm in Calverton, New York. The farm is a popular tourist stopover, and so helps educate people about wind energy. Kevin Shea.

Topics will include a brief overview of wind power history, advances in large-scale wind worldwide, and how these developments drive up the potential for local, small-scale wind. The chapter will also give a brief explanation of how the wind turbine system works. Last, we will outline the significant environmental benefits of wind power, as well as potential impacts, including addressing common myths and areas for concern.

A Brief History of Wind Energy

You might already have a good understanding of wind energy, but let us start with the basics.

Wind is simply air in motion caused by uneven heating of the Earth’s surface by the sun. The Earth absorbs and releases the heat at different rates because it is made of different types of materials. This produces cold and warm air masses that shift continuously. As warm air rises, cool air moves in. Wind is caused by differences in pressure. Where these differences develop, air is accelerated from higher to lower pressure.

Wind has been converted into useful forms of energy for millennia (Figure 1-2). Long ago, wind was used to build or “feed” a fire, spread seed, and dry cloths. Historians believe wind has been tapped to move sailboats for at least 5,500 years. In the 17th century B.C.E., the powerful Babylonian emperor Hammurabi recorded plans to use wind power for ambitious irrigation projects. (That’s the same ruler responsible for Hammurabi’s Code, one of the earliest written systems of law.)

FIGURE 1-2 Wind has been used for millennia to fan fires, spread seed, and dry clothes, as well as for artistic purposes, such as this re-creation of traditional German wind art in Texas. Brian Clark Howard.

It seems that people understood wind energy as a public good even back then. Over time, and with more innovation, wind began to be converted into mechanical energy through windmills, which turned grinding stones for making flour and drove pumps for moving water.

Many historians think the first windmills were invented by the Persians around 500 C.E. (Figure 1-3). These devices were made out of bundles of reeds and wooden frames, and were mounted on vertical shafts (taking the shape of what we now call vertical axis wind turbines, or VAWTs). They were housed in brick or clay walls, with an opening that allowed the wind to enter, and were used to grind grain and pump water. In the first century C.E., the Greek mathematician and engineer Heron (aka Hero) of Alexandria invented a wind-powered musical organ. Similarly, by the fourth century, devotees in Tibet were cleansing their karma via wind-powered prayer wheels. (For good measure, they also had stream-and candle heat-powered prayer wheels.)

FIGURE 1-3 Many historians think the first windmills were invented by the Persians around 500 C.E. Their devices gradually spread throughout the Middle East, and were mentioned in early Islamic texts. Kaboldy/Wikimedia Commons.

Many historians say the world’s first truly practical windmills were invented in Sistan—a region now on the border of Iran and Afghanistan—sometime around the seventh or ninth centuries c.e. These were also vertical axis models, with rectangular-shaped blades and six to twelve sails of reeds or cloth. These early windmills were used to grind flour, process sugarcane, and pump water. Over time, the designs spread throughout the Middle East and Central Asia. They were also sometimes adapted to pump seawater to make salt.

The earliest definitive record of a windmill in northern Europe is a report from Yorkshire, England, in 1185. This example had a horizontal axle, predating today’s horizontal axis wind turbines (HAWTs), and it was used for grinding grain and pumping water. Beer a la wind!

Some scholars have theorized that the horizontal design was adapted after contact with earlier vertical designs, perhaps as a result of the Crusades, but medieval technology scholar Lynn White, Jr., has argued that the Europeans independently invented their windmills (Figure 1-4). According to White, it wasn’t so much a leap of technology as much as an evolution, given that waterwheels were already in use there. Wind-driven versions offered a number of key benefits, such as the ability to work even when the rivers are frozen. Plus, there are only so many babbling brooks to go around, especially when the best ones are already claimed by the nobility.

FIGURE 1-4 During the late Medieval and Renaissance periods, horizontal axis wind turbines sprouted across Europe for pumping water and grinding grain. Can’t you imagine Don Quixote tilting at these windmills in Spain? Lourdes Cardenal/Wikimedia Commons.

In the 14th century, the people perhaps most associated with windmills today, the Dutch, began using the machines to pump water out of their dammed watersheds, expanding their amount of arable farmland, and even permitting them to live below sea level. Many beautiful historic examples of the windmills remain standing today.

American history scholars believe the first windmill built on U.S. soil may have been erected in Jamestown, Virginia, in 1621. After that, a number were built across the continent as colonists expanded. Between 1850 and 1900, an estimated six million small windmills were installed on American farms to drive irrigation pumps. They were made by such firms as Star, Eclipse, Fairbanks-Morse, and Aeromotor.

In 1887, Professor James Blyth of Anderson’s College (now University Strathclyde) in Glasgow, Scotland, built the world’s first wind turbine—meaning a device that harnessed the power of the winds to actually generate electricity. Blyth’s machine was 33 feet high and had cloth sails, and it powered lights in his vacation cottage. Allegedly, when he offered to share his excess electricity with the townspeople, they declined, calling it “the work of the devil.” Blyth would build another wind turbine for a local hospital, but his designs never caught on. Damn him!

In 1888, inventor and engineer Charles F. Brush built a massive experimental wind turbine in the backyard of his Cleveland, Ohio, mansion (Figure 1-5). Atop a 60-foot, 40-ton wrought iron tower, Brush’s team placed a 56-foot-diameter horizontal axis turbine with a rotor composed of 144 blades—which provided a sail surface of 1,800 square feet (an average area of a U.S. home)—and a tail that was 60 feet long and 20 feet wide.

FIGURE 1-5 In 1888, Charles F. Brush built a 12-kilowatt wind turbine in his Cleveland, Ohio, backyard. Wikimedia Commons.

According to Green Energy Ohio, the 20-foot shaft inside the tower turned pulleys and belts, rotating this dynamo up to 500 revolutions per minute. It was extremely inefficient, in part because it was such a solid mass and because it turned slowly. And despite its size, the turbine could only produce a maximum of 12 kilowatts. It could power your New York home today, but the wind had to be strong enough to compensate for the steel shield of blades.

Brush’s wind turbine reportedly lasted for 20 years, although it was obsolete within just a few, since Cleveland soon received grid power, which was more reliable and easier to work with.

In the 1890s, Danish scientist Poul la Cour also built wind turbines, and the technology really caught on in Denmark, which is still a global leader in the field. By 1908, Denmark had at least 72 electricity-producing wind turbines, ranging in output from 5 kW to 25 kW. The largest of these were mounted on 79-foot towers, with four-bladed, 75-foot-diameter rotors. In 1957, another Dane, Johannes Juul, reached an important innovation with a 79-foot-diameter horizontal axis wind turbine at Gedser. This design had three blades and faced upwind, and it established the most dominant design in the industry.

The 1920s, 1930s, and 1940s saw a “golden age” of wind turbines in America, as millions of units were installed across the country (Figure 1-6). Some were used on bridges and for other isolated structures, but most were bought for farms and ranches, where they provided lighting and ran machinery, typically with batteries. Manufacturers included Jacobs Wind, Wincharger, Miller Airlite, Universal Aeroelectric, Paris-Dunn, Airline, and Winpower. Most designs generated a few hundred watts to several kilowatts. The most popular model was a two-bladed, horizontal design from Wincharger, which produced up to 200 watts.

FIGURE 1-6 In the early 20th century, millions of small wind turbines were installed around the world, before widespread rural electrification. Many of these machines still spin today, like this one in Idaho, and some are still used for remote power and pumping. Brian Clark Howard.

During this period, some turbines were used in Africa and in other developing areas, and some were even used on Admiral Byrd’s expedition to Antarctica. At the same time, the Dunlite Corporation sold many small turbines across rural Australia.

The rural electrification programs that started in the 1930s ended this golden age of wind turbine use, since getting grid power meant that it was no longer convenient or economical to keep the small blades spinning. As a result, fewer wind turbines were built for several decades. True, some very small turbines have long been used on boats (Figure 1-7)—in fact, German U-boats even had them in World War II—but there wasn’t a lot of demand.

FIGURE 1-7 Small wind turbines have been used on boats for a long time, as proven by this 1902 image of the grounded ship Chance off New Zealand. David De Maus/Wikimedia Commons.

However, in the 1970s, rising environmental consciousness, the Arab oil embargo, and the back-to-the-land movement combined to feed new demand. At first, many people sought out vintage wind turbines—Jacobs Wind models were especially prized. Gradually, a small industry developed to recondition and service these machines, and over time, companies began to design and build new equipment. Some people also tried making their own wind turbines out of locally available scrap parts, such as hand-cut wooden blades, used car alternators, and old bicycle chains. These designs can work, as triumphantly proved by young Malawian tinkerer William Kamkwamba, the subject and coauthor of the best-selling book The Boy Who Harnessed the Wind (William Morrow, 2009). However, they are a lot of work, are often noisy, and usually don’t produce much juice.

Today, consumers have considerable choice when it comes to small wind turbines. They can shop for full-service wind solutions, or order kits and parts online and do the whole thing themselves. The industry is still relatively immature, especially compared to commercial wind, and many designs are new and without track records or real-world data to back them up. But that is changing, and new certification programs are coming online.

A Brief History of Commercial-Scale Wind Energy

On the utility scale, not much developed during the early decades of the 20th century. In 1931, the Soviets built the WIME-3D turbine near Yalta. This 100-foot-diameter, three-blade rotor was mounted on a 100-foot steel lattice tower. It produced up to 100 kW, meaning it would technically be classified as small wind by most experts today, despite its big size.

In 1941, the world’s first megawatt-scale turbine was built, on the top of Grandpa’s Knob Summit in Castleton, Vermont (Figure 1-8). The massive, 1.25 megawatt (MW) turbine was connected into the local grid, but it only lasted for 1,100 hours, since a known structural weakness resulted in failure. The builders, Palmer Cosslett Putnam and the S. Morgan Smith Company, reportedly couldn’t make reinforcements due to wartime material shortages. It would be about 40 years before anything was tried to that scale.

FIGURE 1-8 The world’s first megawatt-scale wind turbine was built on blustery “Grandpa’s Knob” near Rutland, Vermont, in 1941. Rated at 1.25 megawatts, the project only lasted a brief time, since war shortages prevented repairs. DOE/Wikimedia Commons.

In the 1970s and 1980s, the National Aeronautics and Space Administration (NASA) conducted extensive research on utility-scale turbines. Efforts were coordinated out of Lewis Research Center (now John H. Glenn Research Center) in Sandusky, Ohio, not too far from Brush’s pioneering machine. The wind projects were funded by the National Science Foundation and the Department of Energy (DOE), with support from a public that was hungry for renewable, homegrown energy sources.

Several designs were tested at sites in Ohio, North Carolina, Washington state, and elsewhere (Figure 1-9). Major contractors included General Electric, Boeing, Westinghouse, and United Technologies. The work eventually led to many key innovations, including steel tube towers, variable-speed generators, composite blade materials, partial-span pitch control, and structural components. In 1987, the massive Mod-5B turbine was built in Hawaii, with a rotor of 328 feet and a rated power of 3.2 megawatts. The blades were segmented so they could be transported more easily.

FIGURE 1-9 In the early 1980s, NASA, the DOE, and Boeing built a 7.5-megawatt cluster of three big wind turbines in Goodnoe Hills, Washington. The experimental wind farm was supported by the Carter administration and a public shocked by the Arab oil embargo. NASA/DOE/Wikimedia Commons.

Also in the 1980s, California passed tax rebates for wind power, and this kicked off the world’s first commercial wind farms, the most famous of which is located in Altamont Pass. Those turbines are small (100 kW) and inefficient compared to today’s commercial operations, but they set the stage for an exciting new industry, and they still spin today.

By the way, have you ever noticed which way wind turbines spin? Most old-fashioned windmills had their blades rotate counterclockwise, and that’s how many wind turbines worked, too. However, in the 1970s, the Danes started making all their designs work clockwise, and soon it caught on as an industry standard.

Vertical axis turbines haven’t seen as much development over the years, although NASA has tested them, and there has been a recent resurgence in them, despite some controversies (Figure 1-10). The Darrieus wind turbine, a key vertical style, was patented in 1931 by French aeronautical engineer Georges Jean Marie Darrieus. (More on VAWTs in Chapter 8.)

FIGURE 1-10 A micro-VAWT mounted above solar panels on a light pole in a Brooklyn parking lot. VAWTs have enjoyed a resurgence recently, though they remain controversial. Brian Clark Howard.

Today, wind energy is primarily extracted to generate electricity, although some windmills are still used to pump water, primarily on remote ranches. Although small-scale wind is now overshadowed by commercial projects in terms of investment, political support, and public awareness, the small wind industry continues to show strong growth and considerable promise. Small wind turbines don’t make sense for everyone or for all locations, but they definitely have a role to play in a cleaner future and in smart energy economics.

It’s worth remembering that wind is a renewable energy source, because the wind will blow as long as the sun shines. There is no controversial belief regarding some “peak wind” theory, as there is with fossil fuels. Wind will be here for at least 20 millennia more, and we hope that human beings like you will be innovative enough to reap the benefits.

Recent Growth of the Global Wind Market

You are standing on the highest peak in the American Northeast, the 6,288-foot Mount Washington in New Hampshire. It’s a forbidding landscape of wind-swept rock, home to some of the planet’s fiercest winds. All of a sudden, you are blown over by a terrific gust. You are swooped into the air, out of control, and at the mercy of winds with the amazing speed of 231 mph (103.3 m/s), the fastest ever recorded with an anemometer (outside of a tropical cyclone).¹ While you are up in the air, let’s ride the trade winds across the globe to see what advances are being made in the wind industry worldwide.

Figure 1-11 shows a graph of world-installed wind power capacity for 1996 through 2008. Take this chart with you, because it can give you a glimpse of small wind turbine growth to expect on your journey.

FIGURE 1-11 Global installed wind power capacity for 1996 through 2008, moving steadily up! Global Wind Energy Council/Thomas Splettstoesser/Wikimedia Commons.

Circling the United States, the wind rushes through numerous large-scale onshore (i.e., on land) wind farms. You are blown past the Altamont Pass Wind Farm in California, a bold step in the infancy of the market (Figure 1-12). The 5,400-turbine collection of residential-size turbines initially installed in the early 1980s provided lessons for future development. It has long been cited by conservationists as a primary reason why wind turbines can sometimes do more harm than good, as it ended up killing thousands of birds, including eagles and other raptors (more on this later this chapter). Note that 80 megawatts of turbines are to be upgraded by the end of 2011 to remedy this problem.

FIGURE 1-12 California’s sprawling Altamont Pass is home to one of the world’s most famous wind farms, which was started in the early 1980s. Shown are Enertech models that are considered vintage today. Xah lee/Wikimedia Commons.

On the other side of the coast, a massive offshore wind farm network is being planned from Maine to North Carolina. In between are 100,000 small wind turbines now operating throughout the country, providing about 100 megawatts of generating capacity. This includes boats, homes, farms, and businesses with spinning flags of wind power.

Swoop up to Canada, home to more than half of the small wind manufacturers worldwide, with models in the 30-50 kW range and to three-fourths of manufacturers with models in the 50-100 kW range. Small and utility-size wind turbines power over 1 million Canadian homes, with estimated wind energy potential for 17 million homes.² Despite its recent economic troubles and extended cold temperatures and harsh weather, Canada’s small wind industry has increased by 55 percent over the past two years, according to a new market study conducted for the Canadian Wind Energy Association (CanWEA).

According to CanWEA’s manager for small wind policy, Emilie Moorhouse, the country has an estimated 12 MW of installed small wind capacity. Almost 90 percent of that is due to systems smaller than 1 kW. A large percentage are off-grid, in very isolated and far northern areas.³

Taking the trade winds, we pass over sparsely populated areas of Greenland, the world’s largest island, with harsh climatic conditions and little infrastructure due to cost constraints. Wave a salute to the task forces looking for ways to harvest one of the world’s best onshore wind resources, due to its high average wind speed of 15 mph (7m/s).

At the gateway of Europe, you swoosh through history. You might see remnants of windmills that once dominated the landscape of Holland, also home of the Zeeland small wind turbine test site (Figure 1-13). Also, tip your cap to Denmark up north, which has long been home to pioneers of wind turbine development. Then there is Germany, Spain, and numerous other countries in the European Union that have seen small wind turbines planted like seeds in a field after the government agreed to pay feed-in tariffs for clean electricity wherever the site permits (see Chapter 6 for more on financing).

FIGURE 1-13 The Zeeland small wind turbine test site in Holland, where researchers evaluate different designs. Jeroen Haringman/www.solarwebsite.nl.

In the United Kingdom, which recently added a feed-in tariff for small wind, the growing trend is small, distributed, grid-connected projects (Figure 1-14). The United Kingdom has historically been the second-largest market after the United States, representing 20 to 25 percent of global demand.⁴ The United Kingdom added an estimated 10,000 small wind turbines since 2005, for a total of over 15,000.⁵ Installed capacity now exceeds 20 MW.⁶ There is rising interest in many other countries in the European Union, particularly Italy, where small turbines are seen as offering “made in Italy” potential.⁷

FIGURE 1-14 The United Kingdom recently added a feed-in tariff for small wind, which is helping spur the industry. Pictured is an Ampair 6000 wind turbines in Berkshire. Ampair.

At closer look, you can see a unique turbine application that is just beginning to enter the market around the world, in urban regions. Soaring from the forest of skyscrapers, flats, and municipal parks like Peter Pan on his search for Wendy, you can feel the sudden drop in wind energy as it wraps through the concrete maze. This environment is not generally conducive to effective use of large or even small wind turbines. However, micro-turbines, dubbed urban wind turbines (UWT), are in development (Figure 1-15). If new field-test certification standards arrive for UWTs, it may bring a breath of fresh air.

FIGURE 1-15 Placing wind turbines on rooftops and in urban areas is unlikely to produce much energy, unless the winds are very strong. Pictured is an experimental Honeywell wind turbine on the roof of the Solarium, a green-themed apartment building in Queens, New York. Brian Clark Howard.

Currently, it is wise to be skeptical of those who say any turbines can be placed on rooftops, in urban areas, or in places with a lot of turbulence. Such obstacles take much of the power out of the wind, and wind speed is a crucial factor in the amount of energy that can be produced, as we’ll soon explain. However, most experts think there is potential in this area, if the right factors align and the right technology comes along, for the right price.

Pushing forward, the wind currents accelerate as you approach the western coast of India. The estimated potential for wind-energy production in India is 40,000 MW at 100 feet above ground level. In rural India, small and micro-turbines are lighting up homes of remote villages and powering hundreds of telecommunications towers.⁸

We will conclude your world tour with one of the biggest growth markets: China, which reportedly added about 50,000 small turbines in 2009, for a total of some 400,000 in place by the end of that year.⁹ There may be as many as 100,000 small wind turbines in use by nomadic herdsmen in northwestern China. These small turbines—so compact they can be carted on horseback from one encampment to another—are among the few sources of power available on the Asian Great Plains.¹⁰

“For a young married couple in inner Mongolia, their most revered gift is a wind turbine,” Trudy Forsyth told us via phone from the National Renewable Energy Laboratory (NREL)’s National Wind Technology Center in Colorado. Forsyth is a senior project leader who specializes in testing and certification of small wind turbines, and serves as NREL’s liaison to the American Wind Energy Association (AWEA). “They can take it with them, where they can set it up, and get some lights and TV,” said Forsyth. “Wind turbines are more rugged than solar panels, and it’s windy there.”

Even today, three-fourths of all small wind turbines built are destined for standalone power systems at remote sites, far from the nearest village. Others serve mountaintop telecommunications sites where utility power could seldom be justified.

Although there are other countries to visit, there is only so much space in this book. But take a look at the interactive map from the Global Wind Energy Council on www.gwec.net/index.php?id=9 to get a bigger picture.

We hope you get the idea that there is huge and growing global demand for emissions-free wind power, which can be installed quickly, in many places in the world. Over the past ten years, global wind power capacity has continued to grow at an average cumulative rate of over 30 percent¹¹ (Figures 1-16 and 1-17). Although commercial-scale projects have led the way, the small wind industry has seen strong growth as well, despite the global recession. In general, small wind is still a niche energy player, and it does have some of the limitations of being an immature market, such as difficulty in finding replacement parts and access to skilled labor.¹²

FIGURE 1-16 Commercial wind technology has advanced rapidly over the past few decades; the industry is much more mature than the small wind power sector. Wind Powering America/NREL.

FIGURE 1-17 As the cost of producing energy with large wind turbines has dropped dramatically, production has skyrocketed. Wind Powering America/NREL.

Still, improving technology has given rise to a more cost-effective small wind turbine over the last 15 years, moving closer to the cost of conventional energy sources. For years, small wind turbines have been used to generate power to charge batteries. Technical developments have increased the power rating, efficiency, and reliability of these turbines. Current wind turbines can also now be used either on or off the grid to power homes and businesses. In fact, the fastest-growing segment of the small wind turbine market is that of residential-scale, grid-connected units, between 1 and 10 kW.

Due to advanced technology, wind turbine blades have become lighter, yet more durable and efficient in extracting wind energy. Similarly, the rotor speeds have been slowed down to decrease noise, and vibration isolators have been introduced, particularly for roof-mount models. Self-protecting technologies like the ones developed by WindTide in Ireland help the wind turbine protect itself in case of high wind speeds, including with active pitch controls (explained in Chapter 8) that maximize energy capture at high speeds without permitting the turbine rotor to get the brunt of the heavy gusts.

Some small wind turbines are also available with wireless connectivity, enabling owners to control the system from a distant location, while others come with nifty electronic data displays. Such technological advances have made these wind turbines more like an appliance, enabling it to be part of the household dinner conversation, and a desirable gift on the wedding registry.¹³

Want to fly there for a closer look now…. Scan the locations.

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“The Boy Who Harnessed the Wind” Shows the Importance of Scale

A small, landlocked country in southern Africa, Malawi is among the world’s poorest, and only about 2 percent of its people have electricity. But one young Malawian tinkerer has proven to the world that anyone can improve their lot in life through the power of the wind.

William Kamkwamba’s story has become internationally known, thanks to a TED fellowship, a bestselling book (The Boy Who Harnessed the Wind) and a globetrotting schedule of speaking and TV engagements (Figure 1-18). As Kamkwamba explains in his inspiring, gripping memoir, he was first exposed to the concept of wind energy in 2002 when he was 14 years old, while looking through a textbook at his rural town’s tiny library. With Malawi suffering through a heartbreaking famine, Kamkwamba’s farmer parents couldn’t afford his school fees, and there was only so much work he could do in the parched earth, with no way to irrigate or afford fertilizers.

FIGURE 1-18 William Kamkwamba of Malawi inspired millions by building a wind turbine out of junk.

Impressed by the graceful, intrinsically simple shape of a wind turbine, Kamkwamba wondered if he could build one to pump water and bring lights to his house so he could study when the sun went down. He spent months pouring through tattered engineering texts and scavenging through junkyards and scrap heaps. He even took a part-time job to earn the few dollars he needed to purchase a bicycle dynamo.

While Kamkwamba endured harsh torment by his peers and confused stares from adults, he pressed on. Near his family’s modest home, he raised a 16-foot tower from blue-gum poles he cut himself. At the top of the tower, he and a friend cobbled together a 12-watt wind generator out of used bicycle parts, plastic pipes, tractor fans, and wood. In one of the book’s most dramatic moments, Kamkwamba amazed a crowd of his critics when he first wired a light bulb to his spinning machine … and it glowed dimly.

Soon, Kamkwamba was powering several lights and a radio in his home, and he charged cell phones of grateful passersby for free. He added car batteries for some energy storage, and he improvised a simple overcurrent protection feature (from a nail and speaker magnets) and a 600-watt inverter to convert the machine’s wild alternating current (AC). The blades turned a pulley, which turned an old bicycle wheel, which powered the dynamo. According to his blog, Kamkwamba and friends recently added better deep cycle batteries, and they hope to add solar panels.

Early on, the young boy’s impressive contraption attracted attention from the national authorities and the news media, and before long, he was offered a scholarship to a prestigious school in South Africa (Kamkwamba has since been accepted to Dartmouth University in the United States).

Kamkwamba also built several more wind generators, including some that pump water for irrigation and one that serves a local school in his native Kasungu District. The largest of his machines stands at 37 feet.

Kamkwamba is exceedingly humble, and he is already hard at work helping others in his community. His Moving Windmills Project has partnered with the U.S.-based buildOn.org nonprofit to rebuild his old school, which is in serious disrepair. Kamkwamba also hopes to empower others in the developing world to generate their own energy.

It’s easy to see why William Kamkwamba’s story resonates around the world. It’s a touching example of how a bright, determined individual can lift himself out of poverty through hard work. It’s also a good reminder that, to be a success, a wind turbine doesn’t have to be big or made from shiny, expensive parts.

Although a 12-watt turbine isn’t going to make much of a dent in the typical American home’s energy budget (the annual average is 10,000 kilowatt-hours), that says more about our consumption patterns than it does about the limits of do-it-yourself (DIY) projects. For a family like the Kamkwambas, having the ability to read at night, pump well water, or charge a cell phone without walking into town and paying a fee is a significant improvement in quality of life. Sometimes, we have to rethink our notion of scale and remember that what doesn’t work in one situation may be just the thing for another.

Wind Energy System Components

Here’s a gentle breeze through a complete wind energy system.

Turbine

A wind generator, or turbine, has two functions:

• Collect the wind (blades)

• Convert wind energy into mechanical then electrical energy (generator)

Turbines may come in different shapes and sizes, but in general, the blades and the hub, the center part that turns the shaft, combine to make up what is called the rotor—what we see spin (Figure 1-19). The spinning of the shaft (or stator in some cases) results in generating an electrical charge within the alternator. To maximize the energy harvested, a turbine needs a device that keeps it facing the wind, either mechanical—as in a tail—or electronic—such as the electronic orientation yaw drive.

FIGURE 1-19 Assembling a wind energy system is a challenging task that requires teamwork. Scotsman Hugh Piggott leads workshops on both sides of the pond that have taught thousands of people to do it themselves. Hugh Piggott.

Power Up! Blade size and robustness of the alternator, rotor, and tail to weather through years of high-velocity winds will be one of your major factors in deciding which turbine to purchase. The next factor will be the generator’s conversion efficiency from wind’s kinetic energy to electricity, and the durability of the generator’s components to long-term exposure to air turbulence and high revolutions per minute (rpms) (see Chapter 8).

Tower

The tower puts the turbine up in the location of the “fuel”—the smooth, strong winds that provide the best energy. Wind turbines should be sited at least 30 feet higher than anything within 250 feet (76 m).

Three common types of towers are tilt-up, fixed-guyed (the ones with the supporting wires), and freestanding, or the one where the structure is wider at the base than it is at the top and has a significant foundation. Towers must be specifically engineered for the lateral thrust and weight of the turbine, and should be adequately grounded to protect your equipment against lightning damage.

Transmission Wires

Transmission wires are usually made of copper or aluminum, and they deliver the electricity from the turbine to your conversion assembly (see “Balance of System”) and ultimately to your home and the utility grid. Proper sizing of wire to handle the load, grounding patterns, trenching, and safety measures are discussed in detail during installation.

Balance of System (BOS)

In addition to the primary hardware of turbine, tower, and wires, you’ll need other parts to make your investment work. These other components are often collectively referred to as the “balance of system.”

Charge Controller

In a battery-based system, this smart little box keeps your batteries properly fed and safe for the long term. As the name suggests, a controller governs the charge produced by the wind turbine. It blocks reverse current and prevents battery overcharge. That’s important, because overcharged batteries need more maintenance and wear out quickly.

Nearly all installations require a controller to divert excess electricity if too much is being produced at once, due to high winds. Many controllers also provide intelligent charge regulation, array output optimization, automatic battery equalization, and even built-in datalogging. Chapter 10 on BOS will cover selection and installation of charge controllers.

Battery Bank (Storage)

If your system is off-grid, you’ll need a battery bank—a group of batteries wired together—to store energy so you can have electricity when it’s not windy. A wind turbine can also be hooked up to both batteries and the grid. Produce excess energy that your batteries can’t hold, and you can feed it into the grid, hopefully for a credit. When insufficient electricity is generated or the batteries are drained, electricity drawn from the grid can make up the shortfall. Yet battery banks can provide emergency backup during blackouts.

Only deep-cycle batteries are recommended for wind-electric systems, although William Kamkwamba built his first small turbine in Africa with regular off-the-shelf batteries, and he still had a little juice for a few lights. For wind systems, lead-acid batteries are the most common battery type chosen due to their low cost and wide availability. Sure, lithium-ion batteries would work great, but they aren’t cheap.

System Meter

System meters can measure and display several different aspects of your wind system, including how much power you are producing at the moment, the charge status of your batteries, and how much electricity your home is using. Many of today’s inverters have remote access via personal computer and mobile devices. “Hold on, let me check my status on my smart phone.”

Dump Load (aka Diversion Load, Load Resistor)

A load—some device(s) drawing energy—must be kept on a turbine at all times to prevent it from spinning too fast and overheating internal parts or getting damaged. That load could be the grid or a battery bank. However, if the batteries are fully charged, they can’t accept more juice without damage. In that case, the controller diverts excess electricity to a dump load, which is usually an air or water heating element that “burns off” energy as heat. If you can put the heat to good use, even better!

(Technically, some controllers do not require dump loads if they operate using pulse width modulation shunt techniques to prevent the battery bank from overcharging).

Disconnects and Overcurrent Protection

You’ll need to have a direct current (DC) disconnect one-switch breaker between the batteries and inverter (see the next paragraph) to allow for easy maintenance and to protect the wiring against electrical fires. In many countries, an additional AC disconnect must be located outside the house and near the panel. It typically is a large, one-switch breaker mounted in a metal enclosure. It can provide an extra defense to protect line workers against electrocution from your electricity during a utility grid repair.

Inverter

An inverter converts direct current (DC) to alternating current (AC), which is used by appliances, lights, gadgets, and other devices in most households and facilities. There are two basic types of inverters:

• Battery-based inverters These inverters require large deep-cycle batteries to operate.

• Batteryless, or grid-tied, inverters These inverters are connected to the electrical grid and provide no backup. When the utility grid is down, you can’t make any electricity, because it shuts down the turbine. This is a safety precaution to prevent the accidental electrocution of electric line workers during grid repair in case of an outage.

Back-up Generator

Sizing a system to cover a worst-case scenario, like no wind for weeks, can result in a very large, very expensive, and inefficient battery bank. Therefore, a backup, fuel-powered generator may be necessary, and in fact is almost always necessary in off-the-grid settings.

Petroleum-and diesel-fueled generators produce AC electricity, though a battery charger (either stand-alone or incorporated into an inverter) can convert that to DC energy, which is stored in batteries or can be hooked directly up to the …

AC Breaker Panel

The AC breaker box is the point at which a building’s electrical wiring meets with the power authority. It contains a number of (hopefully labeled) circuit breakers that route electricity to the various rooms throughout a structure. These breakers allow electricity to be disconnected for servicing, and also protect the building’s wiring against electrical fires.

In addition, for their use, utilities usually require an AC disconnect (mentioned earlier) between the inverter and the grid. These are usually located near the utility kWH meter.

Kilowatt-Hour Meter

A bidirectional kilowatt-hour meter (kWH meter) simultaneously tracks how much electricity is being used (measured in kilowatt-hours, kWH) and how much is being generated. It measures power coming from the grid and going to the grid.

Utility Interconnection Equipment

Along with the meter, transformers and any relay switches are commonly provided by the power utility after a net-metering agreement has been signed to ensure that the proper voltage and frequency are provided once the inverter is connected to the grid.

With new technology, you might find that many of the components listed are integrated into various other components. For example, it is common to see an inverter that includes charge controller, monitoring, AC/DC disconnects, and even dump load capability. This makes your shopping quicker and reduces compatibility problems and complications that can arise with separate components. Some products, like Southwest Windpower’s Skystream 3.7 and 600, have integrated nearly all the components within the nacelle, complete with wireless communication to your computer.

Table 1-1 shows a summary of the three common wind system configurations. The grayed areas are components that are found in all systems. We are aware that some of you might want to design a 24-volt system to power your boat, cabin, or one or more direct current appliances, like a DC submersible water pump (we explain electricity in more detail in Chapter 3); however, even the strictest of wind power users will eventually want to use a power tool or appliance that requires AC power. When you are at a point of purchase, print and fill out this form. Note: Any point void of a check box is an indication that the item is not required. The fuel generator is considered an optional item if you are grid-tied, though you may want to consider it in a region with frequent blackouts. In Nicaragua, there could readily be two days without electricity in a given week, and overdraining your batteries shortens their life.

TABLE 1-1 Core Options for a Small Wind System

Direct Drivers for Wind Energy

Let’s start putting wind into your sails, whether you have already committed to building a turbine or are just browsing. Let’s review why the rest of the world thinks small wind energy makes sense.

In fact, the growth of the wind market is being driven by a number of factors, including economic incentives, practicality, values, care for the environment, and the impressive improvements in the technology itself.

To Hugh Piggott, a Scot who has trained thousands of people around the world to make their own small wind turbines through his company Scoraig Wind Electric, and who writes and speaks extensively on the topic, the industry is about what he calls “human scale.” In an interview, Piggott told us he thinks small wind “works on a personal level.”

He said, “It makes people feel that they’re part of the energy generation process, and it gives them a sense of how much energy they use and what it takes to make. We live increasingly disassociated from the stuff we use, but more localized production of food and energy is a healthy thing.”

Piggott told us he doesn’t think small wind is likely to make a big impact on energy trends any time soon. And although not everyone agrees with that assessment, recent history would certainly suggest that he’s right, or at the very least that the industry would have to ramp up vastly more than they are currently to really make a dent in fossil fuel use.

“Compared to offshore wind farms, small wind is incredibly inefficient,” Piggott rightly points out, but that doesn’t mean he sees no value for his work. To him, small wind turbines have a lot of utility, as long as they are smartly sited and installed so they can generate a meaningful amount of electricity. “If you just want to see something spin, buy a whirlygig. They’re a lot cheaper,” Piggott quipped.

“People generally have huge misconceptions about wind energy, and a lot of the time they get deflated,” Piggott added. “Most people assume that they can put something on their roof that will generate most of their electricity in an urban environment. That’s really, really a long way from the truth,” he said.

Author Ian Woofenden told us, “We need to be real about the wind resource, about the fact that energy efficiency is often a better buy, about load analysis, and about what machines can actually do.”

We hope to do just that in this book, and to help you see the situations when small wind does make sense, on a number of levels, including economics. We created this brief list to help you understand some of these factors. Feel free to place a check mark on anything that piqued your interest. In fact, you can send it in to your local wind energy association.¹⁴

Economic Benefits of Small Wind Power

What can wind turbines provide? This list may surprise you.

Free Fuel

Wind is a by-product of solar insolation of the Earth, and is modified and enhanced by terrestrial topography, large bodies of water, and ecological and anthropomorphic activity.¹⁵ But there is no exchange of common currency for the production and transportation of wind.

Return on Investment (ROI)

ROI is a tricky concept, and it’s something most human beings are bad at calculating in their daily lives. Is it better to drive a half-hour out of the way to avoid a $2 toll? Is it worth it to study one more hour for the big test? Is grad school a good decision? Unless you are an investment banker, chances are good that you don’t spend a lot of time estimating your return on investment for very many decisions. Yet most of us opt to consider the question when it comes to renewable energy projects.

The good news is that, with proper understanding and design of a wind power system, including site assessment, personal needs assessment, a reliable product, and government incentives, owners of that system should be able to reap financial benefits that exceed current investment rates over the long term (e.g., certificates of deposit and bonds).¹⁶ Granted, it’s vital that all those factors we just mentioned are in place. Areas with stronger incentive structures and higher electric rates clearly get an advantage when it comes to ROI, and you’ve got to have a system that is high quality and able to access a good wind resource. Small wind installer and expert Mick Sagrillo recently calculated the ROI on a high-profile small wind project to be more than 4,000 years, largely because the owners grossly overestimated the strength of the breezes on top of their building.

“Many projects are being installed as a greenwash thing: they’re not producing any useful energy, and they cost money that could have been spent on insulation and other more effective measures,” Piggott told us.

Something else to think about is maintenance costs. If you can get a service plan, or at least know that your installer can back you up for regular checkups and repairs, that can make a big difference in ROI. As Piggott told us, “Your machine may generate a few hundred dollars a year, and half of that could be blown on a service call if the only technicians available are far away.”

When asked when he thought small wind did have a reasonable ROI, Piggott told us “when you live in a pretty windy place.” He also pointed out that it tends to work really well off the grid, when costs of extending the lines would be prohibitively expensive, or in developing countries, where the only power available is through car batteries that have to be charged at stations, for a fee, then bicycled in. “A lot more people are trying to develop local skill base and manufacturing capabilities, in the developing and developed world, so costs should come down,” Piggott explained.

When asked to estimate a payback period on a “typical” small wind energy system, Woofenden responded, accurately, that there is no such thing as a typical wind generator. But when pressed, he said, “Depends on the resource, utility rate, incentives, reliability, but I would say between 10 and 20 years is a reasonable range.”

Woofenden, who maintains several wind turbines for his off-the-grid home on an island off Washington state, also has a grassroots passion for the technology (Figure 1-20). “Most things we buy have no return at all, because almost everything has a negative return,” Woofenden told us. “I think the payback return question is sort of out of line. I tell potential buyers who ask me about it to cite one thing they bought that they thought about ROI. We subject renewables to that question but not our other choices.”

FIGURE 1-20 Workshop participants build their own small wind energy system from scratch, thanks to the tutelage of Dan Fink. That’s a lot of work, but it can be tremendously rewarding. Dan Fink.

At the other end of the spectrum, wind author Paul Gipe told us that ROI is a critical factor, and that small wind won’t really take off until it gets more favorable. In Gipe’s view, robust feed-in tariffs are the best way to get there. In any case, we’ll get into the money behind the decision in Chapter 6.

Financial Hedge Against Rising Energy Prices

As soon as a grid-tied wind generator (with net metering) is switched on and producing energy for the grid, your cost per kilowatt-hour has been immediately reduced, and the benefits increase as price volatility or inflation raises consumer electric rates. This is worth keeping in mind, because energy prices for many people have been rising sharply over the past few decades, far outpacing inflation. There are a number of reasons for this, including demand outpacing supply, increasing restrictions on new energy projects like transmission lines and power plants, and geopolitical instability. Most experts expect energy rates to continue to climb. Meanwhile, the cost of wind will always be free.

Further, since every kilowatt-hour of electricity produced by wind helps reduce demand for fossil fuels, it can actually help keep costs of those legacy fuels down.

Access to Financial Incentives for Developers and Consumers

It’s no secret that the global small wind energy market, like all renewable markets today, is largely driven by government support policies and regulations. (A lesser-known truth is that conventional energy businesses also receive massive tax benefits and incentives, and part of the reason why energy is so “cheap” is because it is already subsidized.) In the United States, the wind market is supported by federal tax credits and several state-level renewable portfolio standards (RPS), which mandate that a certain amount of energy be provided with renewables.

In December 2008, the European Union (EU) agreed to a new Renewable Energy Directive for a binding 20 percent renewable energy target by 2020. Germany and Spain have had feed-in tariff schemes for several years, and the United Kingdom recently added one for small wind. In the Asia Pacific, government support is also driving wind energy growth. China’s wind-installed capacity has doubled every year since 2006. The Renewable Energy Law, along with other policy measures, is driving the Chinese market even further. In addition, many states in India also have feed-in tariff schemes and RPS in place.¹⁷

Becoming Competitive with Conventional Technologies

With today’s rising coal and gas prices, and the chance of increased environmental regulations on those dirty industries, new wind farms already compete favorably when it comes to economics. With small-scale projects in remote sites or on boats, or for pumping irrigation systems, a wind turbine can be more affordable then connecting to the grid or installing a back-up generator system.

Job Creation and Regional Economic Development

New wind energy will bring significant economic benefits to the participating states, and not just construction and maintenance jobs. Over time, wind component manufacturing should follow expansion. Wind can make a positive impact in terms of employment and revitalization of rural and declining areas.

In fact, CanWEA’s Emilie Moorhouse told us that one of the motivations behind Nova Scotia’s recently passed small wind feed-in tariff was to support the major small wind manufacturer in the province, Seaforth Energy. “They’ll have this double benefit, of environmental and social benefits, plus jobs,” Moorhouse told us via phone from her office in Montreal.

More Americans already work in the wind industry (85,000) than the coal industry (81,000), according to 2009 data from the American Wind Energy Association and the U.S. Department of Energy. Expect the gap to widen in the coming years.

Values and Small Wind

Small wind power also has a number of important benefits that aren’t strictly financial, or that aren’t easy to put a price tag on, at least not with current methods of accounting (Figure 1-21). Let’s look closer.

FIGURE 1-21 Small wind turbine designer, installer, and trainer Hugh Piggott told us he thinks his machines “work on a human scale” to teach people about energy use and production. Hugh Piggott.

Environmental Benefits

Speaking of environmental benefits, wind power, of course, is based on capturing the energy from natural forces, so it has few of the polluting effects associated with “conventional” fuels. Wind energy contributes to the reduction of emissions of various harmful air pollutants (carbon dioxide, nitrogen oxide, sulfur dioxide), and has already played a role in improving regional air quality. Wind power supports efforts to meet emission caps in a cost-effective manner.^{18, 19}_In addition, wind energy uses virtually no water, which, in an increasingly water-stressed world, is a major environmental consideration.

Independence

For many people, it is about energy independence from their power authority. Businesses that pay additional fees for electric demand in excess of their allotment plan, or others who usually couldn’t see options other than accepting the rapid inflation of electrical costs every year, are now considering making their own mini-power plant. For some, it is about “stickin’ it to the man,” by turning the tables on the power authority, and compelling them to pay for the surplus energy produced from small wind turbines through a net-metering or feed-in tariff agreement.

Image Enhancement

Project directors of everything from department stores to manufacturing plants, nurseries, colleges, office parks, hospitals, hotels, municipalities, and much more understand the intrinsic value of appearing “green” to the ever-alert consumer. Wal-Mart and Home Depot, for example, have added very small wind turbines to light poles in selected parking lots. Such projects aren’t always the best idea when it comes to the actual wind resource available, but under the right conditions, they might be a wind-win (Figure 1-22).

FIGURE 1-22 Small wind turbines, like solar panels, can be powerful symbols of environmental commitment. Pictured are AeroVironment AVX turbines on the roof of a new office building at Brooklyn Navy Yard. Brian Clark Howard.

In Queens, New York, Rick Rosa, the sales manager of the new Solarium “green” apartment building, told us that response has been “phenomenal” to the building’s rooftop WindTronics wind turbine. “It has been a guiding light for the neighborhood,” Rosa told us. “It’s a symbol of us being a green building. It brings people over here, and makes them ask about what we did,” he added.

In the case of the Solarium, the turbine is no window dressing, since the building is the first green-certified complex in the borough. That was achieved through energy and water efficiency, use of recycled materials, recycling of debris, and other factors. According to Rosa, the turbine helps makes the facility’s common charges low.

Interestingly, Rosa told us that the main question people ask about the rooftop turbine is “how much power does it generate?”, suggesting that consumers do care that green changes aren’t just cosmetic, and that they make a real impact. (The turbine choice and location in this case are not without controversy, as we’ll soon show.)

Consumer Choice

Over the last few years, small wind turbine technology has improved in quality and versatility. What was once a strictly marine or rural, off-grid solution has evolved to allow renewable energy to enter a wider consumer market. More options are available, including roof-mount turbines, more aesthetic shapes, noise and vibration reduction improvements, integrated sensors, and turbines sized to the customer’s needs, from 150 watts up to 100 kW. As we’ll show you, many of these newer designs are largely untested, and some are controversial, and it still holds that rooftops are rarely good places for turbines. But in general, choice is a good thing, and we’ll walk you through the pros and cons of each major offering in Chapter 8.

Self-Reliance

Wind power technology has evolved and has become more standardized, reducing the learning curve and the risks of investment. This has opened the doors to that significant group who are insistent on relying on their own judgment, knowledge, and abilities in order to survive economic downturns with local resources and not a lot of additional help. Tightening up the bootstraps, they move forward, confident that wind energy is a feasible means to survive, sometimes with most of the energy and material for survival being provided locally. This is certainly not an easy pursuit, but it can be immensely rewarding.

Do-It-Yourself

Although we don’t suggest you try to build your own wind system from scratch without at least some hands-on training or apprenticing, people have successfully done it, and there are bestselling books and websites to prove their feats. There are a number of plans and kits available, as well as instruction books and classes.

More premade small wind systems are designed to be relatively easy to install, but they are still definitely harder than putting together IKEA furniture, and most manufacturers strongly recommend professional guidance. Still, with more certified systems, integration of components, time-tested procedures, and equipment configurations, the guesswork is being reduced.

High Visibility

In history, success has often been celebrated by building prominent structures. When religion was dominant, many towns erected enormous pyramids, temples, and cathedrals. Then, government capitol buildings started to tower over the dwellings of the citizens. Finally, financial services companies came to be housed in glass spires that reached for the sky, seemingly defining the character of Western society. Well, wind turbines placed up on a high pedestal can communicate values for one’s business, farm, or community that could supersede any provocative poster or flowery talk.

The Joy and Satisfaction of It

When it comes down to it, many of the folks we’ve talked to who own small wind generators, or who work in the industry, admit to being in love with watching those blades turn, almost as much as they like seeing their electric meters run backwards. As Hugh Piggott pointed out to us, just wanting to see something turn isn’t reason enough to invest in a wind system—there are much cheaper pinwheels for that. But there is definitely something to the direct experience of making your own power based on the breezes. It’s worth remembering that as much as we like to think of ourselves as rational beings, we make very few decisions based solely on number crunching. If we did, we’d all be driving stripped-down Honda Civics, wearing Dockers, and waiting until movies are released on basic cable.

To one of us, our connection to the wind runs even a bit deeper. Kevin still finds great joy in storms, even the ones hinting that the end of the world is near. He recalls the days of fighting the wind-driven rain to place a roof on his home. He remembers the wind chill that froze the marrow in his bones. Well, even four years later he still smells sweet revenge and wears an evilish grin while watching his spinning turbine as the neighbors’ homes shudder with the gusts and the arcing trees.

Practicality

There are a number of related practical reasons to consider wind power.

Diversity and Reliability of Electricity Supply

So long as we have sunshine, land, and water, wind is highly reliable (although highly intermittent). That is, with enough well-designed systems, the output at any given time should only vary gradually due to varying wind speeds or storms. True, storms can require temporary powering down to protect equipment; however, with weather forecasting, that can be coordinated with complementary energy sources to ensure uninterrupted service. Currently, some utilities tend to malign wind power as “unreliable,” but that seems to be changing as the industry matures, technology improves, and we continue to diversify sources.

Taking a step back, many analysts sensibly point out that it would behoove us as a society to diversify our energy sources. Currently, we are highly dependent on fossil fuels, as well as nuclear power plants that are aging and that are politically very difficult to replace in many countries. The more we can ramp up a diverse set of renewables, the better off we’ll be to weather periods of uncertainty. That includes large and small wind, as well as solar electric and thermal technologies, geothermal, wave and tidal power, biomass, trash-to-energy, and other strategies.

Political Security

Despite a recent blip in the trend as a result of recession, global demand for energy has been increasing sharply. Significant investment in new power generation capacity, grid infrastructure, and geopolitical strategy is going to be required to continue to provide current standards of living in the developed world and to improve the lives of those in the developing world. Yet, supplies of fossil fuels are finite, and petroleum prices are volatile.

In contrast, wind is a massive indigenous power source, available virtually everywhere in the world. As mentioned earlier, wind energy can mitigate petroleum price volatility, reducing the friction among nation-states over scarcity. For example, wind generator installations currently being deployed on military bases are not only being seen as practical, but as one way we can contribute to reducing dependency on foreign oil.

Natural Synergism with Solar Technology

Wind power is directly related to the power of the sun, but the winds continue their ferocity even when the sun’s rays are on the other side of the globe. Wind energy is thus an excellent complement to solar power when the sun has set or during a storm (Figure 1-23). In addition, the two emerging forms of renewable energy have a complementary relationship over the course of a year. In most temperate zones, the amount of energy that can be harvested by solar panels is less in the cooler months, when the sun is lower in the sky. In contrast, the winds tend to blow the strongest in late fall to early spring.²⁰

FIGURE 1-23 Wind and solar power often work well together, as at this home site in Colorado.
Warren Gretz/DOE/NREL.

Diversity of Applications, Including Remote and Off-Grid

Small wind turbines, alone or as part of a hybrid system, can power homes, businesses, farms, ranches, mines, logging camps, boats, and many other things. Wind energy often works very well for remote applications, such as water pumping, ice making, and telecommunications sites. Community small wind projects have been launched for schools, tribes, municipal utilities, and rural electric cooperatives.

CanWEA’s Emilie Moorhouse told us that Canada has been working to develop incentives for hybrid wind-diesel projects for the northern reaches of the country, where some 300 communities live totally remote from the grid. Currently, a five-year grant program is targeting 20 northern communities and six mines. “These communities are dependent on diesel, which is dirty and expensive,” Moorhouse told us. “In a sense, wind is the only renewable technology that’s applicable to the far north. Solar: there’s no sun up there in winter. Hydro: the rivers are frozen in winter. There is no biomass,” she explained.

Moorhouse said wind-diesel projects have already proven themselves in at least 14 communities in Alaska, and she said Canadians are working to build the skilled workforce to deploy and support these hybrid systems. “In the north, there is icing and maintenance issues, so it’s better to have several turbines rather than just one big one,” Moorhouse added.

Resiliency

In the case of commercial wind farms, power is generated by large numbers of generators, so individual failure of one machine does not have large impacts on the total production. This feature of wind has been referred to as resiliency. Even at the home scale, hybrid renewable energy systems permit one form to compensate for the other system when either the wind is calm or the skies are dark.

In a larger sense, adding more wind turbines is part of a smart strategy of diversifying.

Summary

As we have shown, wind energy has a long and colorful history, stretching back hundreds of years. For millennia, people have felt the breeze on their cheeks, watched leaves blow across the path, and asked if that mighty power could be harvested for our benefit. The good news is that it can, and you can choose to be a part of it. In fact, the small wind industry has shown impressive growth in recent years, despite the global recession (Figure 1-24).

FIGURE 1-24A The small wind turbine industry has shown strong growth over the last decade. AWEA

 

FIGURES 1-24B, 1-24C The small wind turbine industry has shown strong growth over the last decade. AWEA.

A small wind system is not cheap or easy to install and maintain. If you are the kind of person who likes to buy the latest shiny new toy, only to leave it in a closet and forget about it a few weeks later, wind power probably isn’t for you. A wind system requires upkeep, as well as a considerable initial investment.

However, wind turbines can also provide many benefits, such as clean power, insulation from rising fuel prices, and considerable satisfaction. To those with a good wind resource, amendable zoning, and a little patience, a wind system can be a smart investment.