Due to unrestrained use, fossil fuels reserves are fast depleting. If predictions are to be believed, in a few years, there will be acute shortage of this non-renewable fuel. While the fossil fuels take millions of years to form, the most feasible option is to switch over to other renewable forms of energy like the wind energy. In simple words, wind energy is a modified form of solar energy.
The Earth is heated unevenly by the sun because of its shape. Whilst the equator gets maximum heat, the poles get the least amount of heat. Along with this, land heats up more quickly than the seas and oceans. This differential heating creates an atmospheric convection system between the earth’s surface and stratosphere, and the energy of the system is stored in the wind movement.
The energy from the wind can be harnessed via a wind turbine. As the changes in wind pressure occur, the blades of the turbine move. This results in the conversion of the kinetic energy of the wind into mechanical energy. The latter is carried through the shaft of the turbine to the generator where it is converted into electrical energy and used for different purposes. Wind energy is the cleanest form of renewable energy. However, it is also associated with a number of pros and cons. Let’s take into consideration each one of them.
The amount of land used for the construction of a wind turbine is an issue of debate. The advocates of wind energy state that the amount of land needed for building a windmill is only equal to the dimensions of its base. All the remaining space can be used for farming. According to them, the farmers can earn lots of money by renting out a portion of their land to companies that harness wind power. They can even build their own windmills and lease them out.
The opponents, on the other hand, believe that space occupied by the wind turbine is many times more than the dimensions of the base. Apart from the area occupied by the base, safety zone is needed, which should be least 5 acres. Besides this, all the trees within 30 acres should also be cleared. Transmission lines have to be laid and roads have to be built for the upkeep of the turbine. For one megawatt of power output approximately 50 acres of land would be needed.
Another issue of distress is the birds that are killed by the movement of the blades. Advocates of windmills state that hundreds of birds are also killed by pollution, planes, and other stationary structures. The opponents insist that the percentage of birds killed by windmills is far greater than those killed by pollution or planes. Noise is another disconcerting aspect of wind turbines. The blade movement produces a lot of noise.
This is another issue of concern. The modern electrical grids are designed to operate efficiently 99.9% of the time; the remaining 0.1% of inefficiency can be easily handled. The situation is a bit different with regards to the wind turbines. They are operational only when the wind blows. Furthermore, if the wind doesn’t blow at constant rate, it becomes difficult to manage the power production. Unlike electrical grids, wind power is not dispatchable — it cannot be started immediately if the wind is not blowing.
Wind turbines do not require expensive boilers, reactors, engines and fuel, so they are relatively cheap. However, the money saved is spent on purchasing high-priced gearboxes, towers, propellers, electronic control systems and forth. Moreover, windmills have a capacity factor of 30 percent — if a wind turbine has one-megawatt power generation capacity, it will produce only 300-kilowatts of power. To maintain reliability, grid energy storage would be required to store energy produced on a windier day. Thus, the running cost of a wind turbine is somewhat high.
Windmills are typically built in sparsely populated areas. From there, the power has to be brought to those places where people are actually living. Transmission lines are used for power distribution, but they are also associated with transmission losses. To overcome this drawback, the cost of the wind power would increase further.