In today's time, scientists & researchers are looking for different types of renewable energy sources which can be used for generating renewable energy that can be further used for power & electricity generation. With the increasing use and high demand for switching to renewable energy sources to fulfill the world's total energy requirements, the use of different types of renewable energy sources has also increased. That's why many types of renewable energy sources are becoming popular in today's time. The most popular renewable energy types are solar energy, wind energy, geothermal energy, biomass, and many others that contribute more than 50% of the total renewable energy consumed by the world.
Among these popular renewable energy sources, wind energy is one of the cleanest energy sources this world has. Wind energy is cheaper and safer than many other renewable and non-renewable energy sources. Still, wind energy is not used on a very large scale compared to the other popular renewable energy sources because of certain limitations. But with the improvements and advancements in the technologies used to produce wind power, the future of wind energy looks bright and promising. The challenges associated with wind energy should be solved so that wind energy's advantages and benefits can be harnessed in full potential. This article provides a complete description of Wind energy, its future, advantages, and generation technologies. This article also provides insights into why wind energy is still not used as the major renewable energy source despite its numerous advantages and what are the limiting factors associated with it.
Introduction to Wind Energy
The type of power or energy generated using wind turbines is known as Wind Energy. The wind power generated using turbines is further used to produce electricity stored in huge size generators. Among all the popular renewable energy sources, wind energy is more sustainable as well less hazardous than others. The negative impacts of wind energy on the environment are next to zero, and that's why wind energy is even considered one of the cleanest sources of renewable energy. Compared with fossil fuels or any other non-renewable energy sources, wind energy production's negative or harmful impacts are very less. The place where wind turbines are located for wind energy production is known as Wind farms. These wind farms consist of individual wind turbines connected with an electric power transmission network, and the electricity generated through wind energy is transmitted through this network.
In the year 2020, wind energy has contributed nearly 5% in the production of electricity whereas, it has contributed around 2% in total energy consumption of the world. The total electricity generated with the help of wind energy was 1600 TWh in 2020. This was a significant increase compared to the previous year's contribution of wind energy in the production of electricity. Among the total energy consumption of the world in 2020, 100 GW alone has come from wind energy, which was also higher than the previous year's contributions. Among these 100 GW of wind energy produced in 2020, most of the amount was produced alone by China, which is also planning to increase the wind energy capacity of 730 GW (Gigawatts) globally in upcoming years. Still, after all these developments, the contribution of wind energy in total energy consumption of the world or total energy consumption in electricity production is very small. This should be addressed in upcoming years to reach the goal of a major increase in sustainable energy contribution. According to research conducted, "If the world has to meet the Paris climate change and really want to fight against this climate change, it should increase the contribution of wind energy in total energy consumption."
Wind energy is one of the variable renewable energy sources (The renewable energy sources in which power supply is not constant), and that's why to increase the production and contribution of wind energy, the problem of energy and power sources management should be addressed. The power management techniques for wind energy should be used while producing it to maintain its demand and supply chain. There are many power management techniques available that can be used with the wind energy production planning, such as grid storage, generators, exporting and importing power from neighboring countries, geographically distributed wind turbines, management for excess capacity, hydroelectric power, or other dispatchable power sources, wind hybrid power system, and many other power management techniques. There is also the need to upgrade and increase the power and storage grids in a wind farm with an increase in the production of wind energy region proportionally. Weather forecasting or predictions also help in the management of wind energy production, and it also allows to be readied for the electric-power network.
Even though the new onshore (Also known as on land) wind farms or power plants are much cheaper than the gas or coal power plants, the subsidies provided for the fossil fuels and their power plans hinder wind power expansion on a large scale. The impacts of the onshore wind farms on the lands occupied are more visible than impacts of any other power plant because wind turbines need to be spread over more land. That's why wind turbines or wind farms are often seen mostly built in rural areas. Many smaller size onshore wind farms can be used to provide a small amount of power isolated off-grid locations or feed some energy into the power grid. Although onshore wind energy is expanding, currently, there are offshore wind power farms because of their higher construction and maintenance cost. In contrast to the onshore wind farms, offshore wind farms have a less visual impact on the lands and provide a stronger and steadier energy source.
Wind Energy and Concepts
The kinetic energy of air in motion (also known as wind) is the wind energy generated using wind turbines. The wind energy generated in a particular wind farm can be calculated through the kinetic energy expression to calculate the total energy produced. The total wind energy generated from an imaginary area 'A' where the wind is flowing during the time 't' can be expressed through the following expression:
E = 1/2 mv2
But, m = Avtp
Therefore, E = 1/2 (Avtp)v2
or, E = 1/2 Atpv3
In the expression given above, some terms are used whose meaning is expressed below:
In the expression given above, it can be observed that the mass expression is replaced with the volume density of the air flowing in the particular area. This is done because of the following rule:
Density = Mass/Volume
=> Mass = Density × Volume
Therefore, the whole term 'Avtp' is used to represent the mass of the air flowing from that particular area in the given expression. Two more expressions for calculating Kinetic energy in the area and wind power can also be derived from the expression. The expression given below derived from the expression given above can be used to calculate the Kinetic energy from the particular area:
Kinetic Energy (KE) = 1/2 pv2
Also, other than this, an expression for calculating the wind power generated in that particular area can be derived from the wind energy expression given above. The expression given below can be used for calculating the total wind power generated in the particular area 'A' when the wind with air density 'p' is flowing from the area for a particular time 't':
Wind Power (WP) = 1/2 Apv3
Because, Power (P) = Energy(E)/Time(t)
The power is expressed in terms of energy consumed or generated per unit time, and therefore the wind power for incident A (Total rotor area of a Wind turbine as expressed above) can be calculated from the wind power expression given above. The wind power is directly proportional to the third power of the wind steam (the speed of wind flow) when the wind power is calculated for in open-air steam environment, which means that as the speed of wind steam increases; the value of wind power generated from the wind turbines also increases. According to a calculation, "The wind energy produced from the wind increases eightfold when the wind stream of the wind flowing through the wind turbines doubles."
The movement of the air across the earth's surface, which is driven by areas of low & high pressure, is known as Wind, and this movement differs in the Northern and Southern Hemisphere. According to research conducted on total wind energy produced across the hemispheres, "The total wind produced in the Southern Hemisphere from 1979 to 2010 was almost 25% higher than the total wind-generated in the Northern hemisphere in the same time period." The atmosphere plays a very important role in the production of wind energy and in maintaining the flow of wind in the hemispheres. It acts as a steam engine, releasing heat at lower temperatures and absorbing heat at higher temperatures. This process sustains the circulation of the atmosphere against friction as it is responsible for the production of wind kinetic energy. Also, it is possible to calculate the potential of wind energy for a specific site, or a region, or the country, or globally through the wind resource assessment. Many specialist-commercial providers in the field of wind energy provide a site-specific and more detailed assessment of the wind resource potential. Unlike the 'static' wind resource, many new generation tools are also coming into the market, which is more advanced tools. These tools are used on different wind turbine models to provide real-time varying stimulations of wind power and energy output at hourly resolutions. In today's time, many in-house modeling capabilities for calculating wind energy potential have also been developed by the many larger wind developers.
Note: The 'static' wind resources are used to calculate wind energy potential by estimating the average power density and wind energy across multiple years.
According to a scientific study, "The total available amount of economically extractable wind energy is much more than the present total use of energy by humans from all sources." The strength and potential of wind energy produced from a wind farm at a given geographical location vary with the wind flow and wind steam, and that's why the total production of wind energy differs throughout the year. This makes wind energy a less reliable source of energy, but as discussed above, with the help of certain calculations and tools, the wind energy potential for a particular region can be calculated for the given time. Different regions have different potentials for wind energy production because of different wind speed distributions.
A wind farm, also known as a wind power station, is a kind of wind power plant or originating source from where wind energy is generated, which is later used to produce electricity. The wind energy farms are shortly known as wind farms, and the farm word is given to them because of the amount of wind energy produced on these sites. The wind farms are also known as wind power plants because, in these sites, a group of wind turbines is present at the same location, and all of them are installed there to produce a huge amount of electricity. Generally, this trend can be seen in a traditional power plant, and that's why these wind farms are also known as wind power plants or wind power station sites. The wind farms vary in size and can range from small wind farms having only a few numbers of wind turbine space available or only a few numbers of wind turbines installed at the sites to large wind farms where multiple numbers of wind turbines are installed. The space available in large wind farms is much greater than the space available in smaller wind farms. There are many types of wind farms according to wind turbines, their sites, or space available, but usually, the wind farms are classified into two types only that are given below;
1) Onshore Windfarms
2) Offshore Wind Farms
Both onshore and offshore wind farms can have a large number of wind turbines installed as well as have proper space for generating electricity through the wind energy produced from these wind turbines. Apart from this, the land left between the two wind turbines installed in a wind farm can be used for agricultural or any other purpose. This utilization of spaces between wind turbines helps reduce the challenges faced in the production of wind energy. One can use these spaces for all the agricultural-related purposes, growing trees of some specific species, passing a route, animal husbandry, and many other purposes.
The wind turbines installed or located in a wind farm are connected to each other through an interconnected power connection system method having low or medium voltage (mostly 34.5 kV). Apart from this power connection system, the communications network is also used to interconnect all the wind turbines located in a wind farm. Wind turbines with all such interconnected networks can be found in both offshore and onshore types of wind farms. Wind farms are so much to study, and only the field study of wind farms will help the students & learners to seek expertise in this field. The number of wind farms is also increasing with the increasing demand for renewable energy and more dependency on wind energy among the available renewable energy sources.
Wind Energy: Advantages & Benefits
Wind energy is among one of the most popular renewable energy sources that are used in today's time for the production of electricity without impacting the environment. There are numerous advantages of wind energy which shows that there is a lot of potential for wind energy to become the major renewable energy source. Wind energy, in general, also have so much potential to contribute as a major source upto a larger extent in the total electricity production of the world. Therefore, investors are much interested in investing in those technologies or companies oriented towards finding safer and cheaper methods for harnessing wind energy globally. This is because harnessing wind energy always remains attractive because of its tremendous advantages. Yes, wind energy indeed offers multiple advantages other than being a popular renewable energy source. And that's why the demand and production of wind energy have been increased rapidly in the past two or three decades. In today's time, many big companies and even some countries are much interested in investing in wind energy and emerging technologies related to this sector so that the overall production of wind energy can be increased to a larger scale. Wind energy has so many benefits that include an energy source available for free of cost, durability, and many others, making wind energy a standout renewable energy source that should be looked forward positively.
There are numerous advantages and benefits of preferring wind energy as the major energy source for electricity production among all the renewable energy sources, and some of these advantages are also listed below:
(1) A free of cost fuel:
Wind energy is a renewable energy source, and similarly to many other renewable energy sources, wind energy is also free of cost fuel that provides a boost to the economy of a country. Wind energy is free for everyone, and there are no charges on wind energy produced through the flow of wind. There are only some costs that can be included in the wind energy costs, but since these costs are one-time and very negligible to the benefits offered by wind energy in the long term, wind energy is called one of the absolutely free energy sources. The wind turbines located on any onshore or offshore wind farms do not require any kind of manual or technological assistance and produce energy only with the help of wind flowing through the farms. The wind energy produced from the turbines is only needed by the wind to move the wings of turbines so that kinetic wind energy can be generated through these turbines. This means that installation costs of wind turbines and generators are the investments required for the production of wind energy, which is very small compared to the benefits one will get from wind energy production. This cost ratio also reduces with the increasing production of wind energy from a given wind farm.
(2) Boosting the economy:
Wind energy is a free source of energy and only requires only one-time investment in the installation of wind turbines and electricity generators. That's why it saves the money of the central government of a country used in the production of electricity and reduces the electricity rate per unit for the common citizens of the country. That's how wind energy is proving as a critical source that can boost the country's economy by saving its yearly expenses on the production of wind energy. The central government of a country can use these saved expenses on other focused sectors, which will not only help the government to grow these sectors but also help them to generate maximum revenues from these sectors. That's how the production of wind energy helps boost the economy of a country both directly and indirectly.
(3) One of the cleanest forms of energy:
Wind energy is also known as one of the cleanest forms of energy when both renewable & non-renewable energy sources are taken into consideration. Wind energy is known as the cleanest energy source because the production and generation of this energy form don't release any harmful elements into the environment. Any kind of harmful elements or chemicals released during wind energy production, or electricity generated from wind energy, is rarely reported.
(4) A Friend to the environment:
Wind energy is known as one of the rare energy sources that are friendly to the environment and do not possess any threat to the environment. Apart from this, wind energy is also known as one of the cleanest energy sources, and that's why most environmentalists also prefer wind energy. These environmentalists are always in favor of large-scale production of wind energy and can be the best alternative option to the fossil fuels that are going to end very soon (in the next 30-40 years, fossil fuels will not be available in this world if the current rate of consumption is continued). Wind energy comparably produces very less threats to the environment when it is compared with the other renewable and non-renewable energy sources. Harmful effects produced by wind energy is very much negligible compared to the benefits offered by wind energy.
(5) Doesn't affect the Farmland:
The land left between the two wind turbines installed in a wind farm can be used for agricultural or any other purpose. This utilization of spaces between wind turbines helps reduce the challenges faced in the production of wind energy. One can use these spaces for all the agricultural-related purposes, growing trees of some specific species, passing a route, animal husbandry, and many other purposes. The advancement in technologies provides options to set up wind farms on wind turbines in the places such as farmland and agricultural land.
(6) Reduce our dependencies on fossil fuels:
As already mentioned, wind energy can be the best alternative option to the fossil fuels that are going to end very soon; it can help reduce its dependencies on them. In the next 30-40 years, fossil fuels will end, and at that time, the world will need to look for the best alternative renewable energy sources. At that time, wind energy could stand out as the best option to fulfill the energy source requirement of the world for the production of electricity.
These are the major advantages of preferring wind energy as the major energy source for electricity production among all the renewable & non-renewable energy sources.
Wind Energy: Disadvantages & Limitations
The major reason behind the slow growth of wind energy, despite its potential, is the limitations and challenges associated with wind energy. There are some major disadvantages or limitations that are associated with the production of wind energy which are given below:
(1) Wind energy produces huge & many threats to the wildlife because of rapid forest cuts
(2) While wind turbines are cleanest in generating wind energy, it is often observed that they are very noisy and causes noise pollution
(3) Too much expenses and destructions are caused during the installation of wind turbines or setting up wind farms
(4) Generating wind energy is too much unreliable and very unpredictable
These challenges should be addressed in the upcoming years so that the production rate of wind energy can be increased significantly, and the world's dependency on this renewable energy source can be increased.