* This compare and contrast is about solar energy and wind energy.
* I found that the conclusion sounds awkward and may be off-topic, in addition, I am unsure if I need to add a concluding sentence after each body paragraph.
Barrack Obama (2009) once said "But to truly transform our economy, protect our security, and save our planet from the ravages of climate change, we need to ultimately make clean, renewable energy the profitable kind of energy". Indeed, the reckless consumption of fossil fuels has greatly damaged the environment and as a consequence, humans have never been so eager for clean energy like today. In fact, there is already renewable, clean energy in use today, such as solar power and wind power. Although both wind power and solar power are clean and renewable, wind power and solar power differ in terms of their method of conversion and conditions for use.
One significant difference between solar power and wind is their method of conversion. In a solar electric system, electricity are generated by bundles of photovoltaic cells, which is also known as solar panels. Photovoltaic cells are usually made of silicon and act as a semiconductor (W. Priesnitz, as cited in Williams, 2013). As the sunlight pass through the solar panels, "[p]hotons in sunlight are absorbed by silicon and electrons are knocked loose from their atoms, allowing them to flow through the silicon to produce electricity" (W. Priesnitz, as cited in Williams, 2013, p.62). On the other hand, wind energy is converted into electricity using wind turbines. W. Priesnitz (as cited in Williams, 2013) states, "The blades on a wind turbine use lift the same way airplanes do" (p. 63). As the wind passes over the blades and creates lift, both the blades and the shaft connected to the blades are spun. Afterwards, the spinning shaft rotates the electromagnets inside a copper wire coil within the generator. While the electromagnets is rotating, electric currents are created and transmitted as electricity (W. Priesnitz, as cited in Williams, 2013).
Another distinction between solar power and wind power is their conditions for use. Since solar power is the conversion of sunlight into electricity by solar panels, solar panels have to be exposed to the sun in order to harness energy. Therefore, solar panels are usually seen in regions with high insolation levels and they are installed on south-facing sloped rooftops. In addition, solar panels need to be kept away from the shade of trees and other buildings to receive the maximum amount of sunlight (W. Priesnitz, as cited in Williams, 2013). In contrast to solar panels, wind turbines have to be attached to roofs or towers to ensure that there is enough air passing through the blades. However, W. Priesnitz (as cited in Williams, 2013) mentions that the inconsistent flow of wind in the city has greatly restricted the efficiency of wind turbines on roofs. As a result, the majority of wind turbines are attached to high towers in coastal areas.
Although both solar power and wind power are never-ending and create absolutely no pollution, they differ in some aspects including mechanism and conditions of use. Some people might argue that wind power is more stable than solar power, and others might favor the expandability of solar panels. However, the biggest concern at present, is the termination of conventional energy consumption.