Wind energy is one of the most accessible forms of renewable energy. It’s good for the environment, cheap, reliable, low maintenance, and very plentiful.
Wind power is the fastest growing form of renewable energy today. Whether produced on a large scale wind farm, or a small-scale wind power system, it can be a very cost-effective way to literally harness energy out of thin air.
Let’s take a look at what causes wind cycles, how wind is collected in wind turbines to produce electricity, pros & cons of wind energy, how much is available, and the future of the wind industry.
What is wind power?
In simple terms, wind power is harnessed kinetic energy from the wind using a device such as a wind turbine to produce electricity. This electricity can then be used for normal everyday energy needs for homes, buildings, power plants, or electrical grids.
The use of wind energy has played an important part in human civilization. Humans began using sails to propel boats and ships around 6,000 years ago. Windmills have also been an important tool for agriculture & water pumping.
Though, it wasn’t until 1890 that windmills started being used for electrical generation. Larger metal blades replaced the old wooden blades and made them more efficient & longer-lasting, and ever since then we’ve been steadily improving upon it.
How do Wind Turbines Work?
The wind turbine (or wind machine) is the most effective device for harnessing wind energy. Here’s a simple explanation of how it works:
- The kinetic energy of wind is “caught” by the angled turbine blades.
- The blades rotate based on how much wind speed is captured.
- This rotating movement turns a wind generator.
- The generator produces electricity.
Although it’s a simple process, the design and technology have evolved to become somewhat complex. Even small changes in the design can drastically alter the operation of the turbine, and ongoing testing and experimentation is constantly optimizing these factors.
The turbine is generally mounted onto a large tower to take advantage of the higher wind speeds (the higher the altitude – the stronger and less turbulent the wind).
These can produce anywhere from 100 kilowatts to a several megawatts depending on the size.
Smaller turbine systems can be complemented effectively with solar panels. When the sun is not shining, winds tend to be stronger. On the other hand, when the sun is shining, solar panels can make up for lost wind power.
The two basic types are the horizontal axis wind turbine (HAWT) and the vertical axis wind turbine (VAWT).
These are the most common type of turbines, with an axis that is parallel to the ground. You’ve most likely seen a few of these sprinkled along the open plains, hilly terrains, or even offshore wind power plants along coastline. As of now, they are the most cost effective and reliable.
These types of turbines are relatively new, and have a vertical shaft that rotates perpendicular to the ground. The main advantage is that the wind can be coming from any direction and it will still function properly. This can be beneficial in areas where the wind direction is unpredictable and changes often.
They can also be built closer together and keep the same level of energy production, unlike the horizontal type.
The disadvantages are that they can stop working when winds are strong, the blades break down much faster because of torque, and they are more expensive.
Pros and Cons of Using Wind Energy
- No pollution – There are no hazardous wastes involved, and therefore no water pollution. It even takes away pollution from otherwise used carbon emitting energy sources. Each year, wind power displaces about 35,000 tons of nitrogen oxides, 58,000 tons of sulfur dioxide, and 25 billion tons of carbon dioxide.
- Reliability – There will always be wind available, which makes it one of the most accessible sources of energy. On the other hand, fossil fuels will eventually run out. They also need to be extracted from the earth, refined, and transported (all of which require extra energy).
- Low Maintenance – A well-designed wind turbine will last for 20-30 with regular inspections and minimal preventative maintenance.
- Inexpensive – Wind power is overall the cheapest renewable energy source. Recently, high demand and new technologies have allowed the price to become competitive with standard energy prices. Even despite these hard economic times, it is the fastest growing source of electricity, nearly doubling every three years. As market confidence gets even stronger, the price will most likely lower even further.
- Good for the economy – Just like any other emerging industry, wind energy will provide new engineering, manufacturing, and construction job opportunities. Best of all, everything can be kept at the local level to help develop self-sustainable communities.
- Dependence on wind speed – The distribution of wind is not always favorable for certain areas. Some locations simply don’t get very much wind, rendering wind turbines a less economical solution. When wind speeds are not enough to produce enough electricity, backups must be in place.
- Appearance – Many find the sight of large wind turbines to be unappealing because they take away from the natural beauty of the land. For example, construction of wind farms are being proposed in places like Nantucket sound, but has been met with some community protest. Local laws may also restrict wind turbine usage for aesthetic reasons.
- Wildlife safety – Wind turbines can kill birds, bats, and insects that accidentally fly into the blades. It is definitely an important concern, but when compared to the number of deaths caused by oil spills, hazardous waste, and other pollutants caused by fossil fuels, the numbers are relatively very small. Also, as turbine blades get bigger, due to improvements in design and technology, they will move at a slower rate and greatly reduce the amount of accidents.
- Land Space – Turbines need to be separated with enough open space around them to collect wind efficiently. If they get too close together, they will essentially be sharing the same wind. However, the ground area can still be used for things like agriculture and livestock production. I’m sure the cows don’t mind!
- Noise – Wind turbines can produce a noticeable swooping noise. Therefore, it is best to keep some distance from population centers. Also, as they continue to grow in size, this will become less of an issue.
Availability of Wind Energy
Just how much power can we get from the wind?
In 2010, about 2.3% of electricity in the US comes from wind power. With that amount of electricity, we could power about 9 million homes (the entire state of Texas). Incidentally, that 2.3% is also enough displace around 62 million tons of carbon dioxide emissions.
We’ve barely even scratched the surface. Currently, the United States is the global leader in wind energy. We’ve come a very long way from where we were just 20 years ago. In fact, the costs of wind power have dropped about 90% since then. There are a few reasons for this: increased demand for renewable energies, better technology, government incentives, and market confidence just to name a few.
The wind power industry is indeed looking very promising. In July 2008, the U.S. Department of Energy put out a report titled “20% Wind Energy by 2030 – Increasing Wind Energy’s Contribution to U.S. Electricity Supply“.
This is a very ambitious goal, but very doable. I have a feeling that we’ll be seeing a lot more wind in the future.
In the world of energy, the trend is definitely heading towards utilizing what mother nature has provided us. Energy is all around us, whether it’s from the Sun, the Earth, or the wind. It’s virtually infinite, and is ours for the taking. All we have to do is come up with creative ways of doing so.
Wind energy has become an important alternative energy source that could possibly even rival fossil fuels in the future. We’ve made so many advancements in wind technology in the past 20 years. In this age of technology, just imagine what we can accomplish with wind energy in the next 20 years!