Wind Farming – Energy Solution orPosted: May 7, 2013 | |
We often think of wind farming as a new concept but the truth is humans have been using wind power for 3,000 years. Most of us can think back to windmills turning milestones to grind grain into flour or the small windmills on farms during the 1930’s pumping water up from underground wells when the blades spun at 15 MPH or higher. If we have been using wind power so prolifically through history why is there so much attention given to it today? To properly answer that question we first need to understand how these farms work.
What is wind?
Seems like a simple question but understanding exactly why the wind blows is integral to choosing wind farm placement. Think of wind as you would liquid, the difference being the particles are gas rather than liquid. Interestingly wind is a result of the center of the galaxy, our sun. The sun heats a certain area of land; the air around that land mass absorbs some of that heat. At a certain temperature, that hotter air begins to rise very quickly because a given volume of hot air is lighter than an equal volume of cooler air. Faster-moving (hotter) air particles exert more pressure than slower-moving particles, so it takes fewer of them to maintain the normal air pressure at a given elevation.
Same idea as a hot air balloon or how soaring birds stay aloft without flapping their wings.
When that lighter hot air suddenly rises, cooler air flows quickly in to fill the gap the hot air leaves behind. That air rushing in to fill the gap is wind. f you place an object like a rotor blade in the path of that wind, the wind will push on it, transferring some of its own energy of motion to the blade. This is how a wind turbine captures energy from the wind. The same thing happens with a sail boat. When moving air pushes on the barrier of the sail, it causes the boat to move. The wind has transferred its own energy of motion to the sailboat.
What are the parts of the wind turbine:
1. Rotor blades – The blades are basically the sails of the system; in their simplest form, they act as barriers to the wind (more modern blade designs go beyond the barrier method). When the wind forces the blades to move, it has transferred some of its energy to the rotor.
2. Shaft – The wind-turbine shaft is connected to the center of the rotor. When the rotor spins, the shaft spins as well. In this way, the rotor transfers its mechanical, rotational energy to the shaft, which enters an electrical generator on the other end.
3. Generator – At its most basic, a generator is a pretty simple device. It uses the properties of electromagnetic induction to produce electrical voltage – a difference in electrical charge. Voltage is essentially electrical pressure – it is the force that moves electricity, or electrical current, from one point to another. So generating voltage is in effect generating current. A simple generator consists of magnets and a conductor. The conductor is typically a coiled wire. Inside the generator, the shaft connects to an assembly of permanent magnets that surrounds the coil of wire. In electromagnetic induction, if you have a conductor surrounded by magnets, and one of those parts is rotating relative to the other, it induces voltage in the conductor. When the rotor spins the shaft, the shaft spins the assembly of magnets, generating voltage in the coil of wire. That voltage drives electrical current (typically alternating current, or AC power) out through power lines for distribution.
How do power companies choose the land and acquire it to build wind farms?
What makes a good windsite:
Sustained wind speeds are critical to a project’s economic viability. Wind turbines require a minimum annual average wind speed of about 15 mph, or 6.7 meters per second. The proximity of turbines to electric transmission lines is another important factor in evaluating the economic viability of a project. Due to the high costs associated with building transmission lines, most wind projects are located within three miles of high-voltage transmission lines.
Also, land features (hills and ravines), vegetation, and nearby structures can affect how valuable a site is for wind energy development. In the Northeast, high hilltops, relatively free of trees and buildings, are favorable for a wind energy project. Factors such as the accessibility of the land for construction, soil type, and terrain impact construction as well as maintenance needs and costs. Environmental impacts related to view-sheds, noise, birds, wetlands, and historical preservation are crucial to the viability of a project and its community acceptance.
Two Forms of Payment
A farmer who signs a contract for the installation of a wind turbine on his farm land will typically receive two types of payments. The initial payments are a lease of the development right for the land. The leasing company locks up the right for a period of three to five years to start building wind turbines on the land. A 2009 report from North Dakota State University reports this option lease pays two to ten dollars per acre to the farmer. Once the company starts building a wind turbine, the lease changes to payments based on the electricity produced by the turbine.
Ongoing Wind Turbine Payments
The payment to a farmer for a completed wind turbine can be based on one criteria or a combination of several. One option is an annual payment based on the rated capacity of the turbine. Another is a flat annual payment per turbine. Some contracts include a payment based on a percentage of the value of electricity produced by the wind turbine. The typical length of a wind turbine contract with a farmer is 20 to 25 years. The contract should include an annual rate increase factor to insure the payments keep up with inflation.
Typical Wind Turbine Payments
The payments for a wind turbine will vary based on the location and the utility company. Here are some published payment amounts from different states. A wind turbine contract from 2009 in Indiana paid $1.10 per megawatt hour but not less than $3,500 per megawatt rated capacity per year. The North Dakota State University report listed payments of $4,000 to $6,000 per megawatt of rated power or royalties of three to five percent of gross electricity sales. A Penn State news release concerning farms in western New York quoted farmers being quoted $3,500 per two megawatt turbine per year plus royalties of four to five percent of the electricity produced.
Wind Turbine Considerations
Large commercial wind turbines have rated production capacities of one to two and a half megawatts. A farmer would earn $10,000 from a two-megawatt turbine with a $5,000 per megawatt per year payment. Wind turbine contracts are very long term and farmers should protect themselves against turbines not producing the projected amounts of electricity and the cost of eventual removal of a turbine. Turbine payments should have an indexing mechanism to allow payment amounts to increase in future years, protecting the buying power of the payments to the farmer.
How much does it cost to build one turbine?
Most of the commercial-scale turbines installed today are 2 MW in size and cost roughly $3-$4 million installed. Wind turbines have significant economies of scale. Smaller farm or residential scale turbines cost less overall, but are more expensive per kilowatt of energy producing capacity. Wind turbines under 100 kilowatts cost roughly $3,000 to $8,000 per kilowatt of capacity. A 10 kilowatt machine (the size needed to power a large home) might have an installed cost of $50,000-$80,000 (or more) depending on the tower type, height, and the cost of installation. Oftentimes there are tax and other incentives that can dramatically reduce the cost of a wind project.
What is the benefit of wind power:
- The creation of wind energy is “clean”. Unlike the use of coal or oil, generating energy from the wind doesn’t produce pollutants or require any harmful chemicals.
- Wind is free. If you live in a geographical location that receives plenty of wind, it is there for the taking.
- As a renewable resource, wind can never be depleted like other natural, non-renewable resources.
- The electric company may end up owing you. If you generate more electricity than you need from wind power, it can be fed back into the grid and you’ll receive credit.
- The cost of producing wind energy has dropped significantly in recent years, and as it gains popularity, it will continue to become more affordable.
- You will recoup the cost of purchasing and installing your wind turbine over a relatively short period of time.
- Wind turbines can provide energy for many homes. You don’t necessarily have to own a wind turbine in order to reap the benefits; you can purchase your electricity from a utility company that harnesses wind energy.
- Tax incentives are offered for installing wind turbines on the federal and state levels.
- Land owners who rent land to wind farms can make quite a bit of extra money, and wind energy also creates new jobs in this growing technology field.
- Wind turbines are considered by some to be beautiful. The modern versions look nothing like pastoral Dutch windmills, but they are white, sleek and modern.
- Wind energy reduces our dependence on fossil fuels from foreign countries.
- Wind doesn’t always blow consistently, and turbines typically operate at only 30 percent capacity. If the weather is not in your favor, you may end up without electricity (or at least you’ll have to rely on the utility company).
- Severe storms or extremely high winds might cause damage to your wind turbine, especially when they are struck by lightning.
- The blades of wind turbines can sometimes be dangerous to wildlife, particularly birds.
- Wind turbines create a sound that averages around 60 decibels, and if you don’t have enough space to locate it away from your house it may prove to be a nuisance.
- Some people believe that wind turbines are unattractive, so your neighbors may complain.
- Compliance with city codes and ordinances may be bothersome when you are trying to install a wind turbine. In some cases, height restrictions may prevent you from installing one.
- Wind turbines and other equipment required to create wind energy can be very expensive up front, and depending on where you live, it may be difficult to find a vendor and someone who can maintain the equipment.
- It requires a lot of open land to set up wind turbines, and cutting down trees sort of defeats the green purpose. Desirable areas to install them are often located far from dense urban areas that could benefit the most from their power.
- Wind turbines may interfere with reception for televisions or other equipment.
Summary from my point of view:
I am all for renewable energy, reducing oil dependency foreign and domestic, and creating more jobs, however while doing research on this piece something didn’t sit right with me. Many local people cite health issues about the noise of the turbines, the strobing effect of the turning blades, and the dominance they have on the land scape. While I have never lived close to a turbine I have lived by rail road tracks, freeways, football stadiums, and downtown areas and have learned to cope with the noises, lights, and smells with which these areas are associated. Esthetically I find turbines to be beautiful and majestic in their own right.
I support community’s right to have a say on whether or not their neighbors should build a 350 foot monolith that will shadow their land and create strobing effects on their windows and yard. If the community votes it in, stop complaining.
What concerns me is the fiscal push behind these farms. The farmers who lease their land really get nothing back when put in perspective what the utility is making. Also these are often government subsidized projects so taxes are building these wind farms at $3 million a turbine. If they build seven wind turbines that’s $21 million. The American government has spent billions developing this technology and millions subsidizing it. Imagine if the government had put that money into improving the average American home’s appliances, energy consumption reduction education, and solar panels on homes? While the government has spent money on the former, far more was spent on wind.
The utility companies are also very aware of how to make money hand over fist on wind. When a utility sells a wind farm to another utility its as if those turbines were just built and all tax breaks come flooding to the new owners even though they simply purchased used and likely outmoded equipment.
Much of the land wind farms are built on is simply leased. When these farms break down or aren’t viable anymore will these leases be renewed? Probably not and the farmers will be the ones left with massive concrete foot prints and huge structures towering over their land waiting to topple. The cost of deconstructing one of these things is astronomical. Moreover they are very difficult to fix since they can be 650 feet in the air. When they are hit by lightning they are allowed to burn until the flames die naturally raining fiery debris for miles, simply because you cannot put the fire out. They are just too tall.
It seems to me this tech will be obsolete rather quickly. From what I understand the first generation of turbines have already gone the way of the buffalo. Seems like a lot of money and materials for something that can’t be repurposed or even removed.
They also are very hard birds and the air pressure of the blades spinning at 150 MPH cause bat’s lungs to explode. Yes. EXPLODE. Hope everyone likes mosquitos. Maybe we can make renewable energy of the billions upon billions of the blood suckers when all their natural predators are dead or gone.
Lastly, wind turbines are the only power plants that draw off the grid. That’s right, they take power. There are a series of brakes to keep the rotors from spinning to fast or not at all. This means when the turbine is shut down because it’s broken or spinning faster than it can safely manage they put on the brakes and that energy comes from the rest of the grid, so while they operate at 30% capacity they waste energy when shut down or being regulated.
Clean energy is paramount to our survival, but wind turbines seem too costly, short-lived, and untested to warrant the amount of money, time, resources, and public discourse spent on them. We absolutely need renewable energy and wind may have some answers but lets rein it in a bit.
The real answer is to consume less. Do one thing today to keep the planet livable that much longer. Turn off lights, unplug unused appliances, ride your bike to work, bring a reusable bag to the market. A little everyday and it will become a lifestyle. That is the real answer to the energy issues we face today.
Drive fast. Take chances. Thanks for reading.