Wind energy is an alternative energy that can supplement other power sources, such as hydro. While most turbines operate at a 25% load factor over the course of a year, some are capable of reaching a 40% load factor, making it a good choice for economic back-up. However, it’s important to note that onshore sites are cheaper to set up than offshore ones. Offshore sites, on the other hand, are more expensive to run.
Hydroelectricity
In the case of hydroelectric power plants, water is impounded at higher elevations, such as a lake or river, and then pumped uphill to drive hydraulic turbines. The water is then released from the higher pool and flows back down to the lower reservoir. The powerhouse is then constructed on one flank of the dam. In some instances, the powerhouse is situated in a steep gorge, with the reservoir acting as a spillway during floods.
Hydroelectric power plants do not produce emissions, unlike fossil fuels. Hydroelectric power plants are considered one of the cleanest forms of energy compared to fossil fuels. In 2005, hydroelectricity consumption worldwide reached 816 GW. This includes both small and large hydroelectric power plants. Considering that wind and water are renewable sources of energy, hydroelectric plants are a viable source of clean energy. Hydroelectric power plants can generate large amounts of electricity for local communities.
People have long harnessed the power of falling water to produce electricity. In the United States, hydropower represented more than a quarter of all renewable electricity generation. Hydroelectric power also lags far behind fossil fuels and nuclear power. Despite this, it is still a major source of energy, accounting for 17% of the nation’s electricity production. However, its share has dwindled as other renewable sources have grown in importance.
Solar photovoltaic technology
Today, PV and CSP technologies are widely used to produce energy. These technologies are becoming increasingly popular as costs are dropping. Fortunately, they are fully competitive with conventional sources in a growing number of locations. In addition, solar photovoltaic technology is “native” energy, meaning that it is available virtually everywhere on the planet. This means that it reduces dependence on energy imports, contributes to wealth creation, and enables sustainable development.
The use of solar PV as a primary source of wind energy is growing rapidly, with worldwide installed capacity at over 515 gigawatts as of 2018. The total power generated by this technology is now more than 500 TWh per calendar year – nearly 2% of global electricity demand. Currently, more than 100 countries use solar PV, with China leading the way with the most capacity, followed by the United States, Japan, and Germany. Unfortunately, this growth has been slowed down in Germany due to recent economic crisis.
The efficiency of solar photovoltaic cells varies, depending on the technology and semiconductor material used. Commercial PV modules tended to be only 10% efficient in the mid-1980s, but by 2015, this figure had increased to about 15%. State-of-the-art modules can now reach efficiencies of almost 20%. Researchers have also demonstrated that experimental PV cells can reach nearly 50% efficiency. One PV cell can generate around 0.5 to 2 Watts of electricity.
Wind turbines
According to the National Renewable Energy Laboratory (NREL), the average wind turbine is made from steel, fiberglass, resin, plastic, and iron, with the remaining percentage being foreign-sourced. Wind turbines are primarily composed of steel, but they can also be made from other materials, including cast iron, copper, aluminum, and plastic. Most wind turbine components are manufactured in the United States, with sixty to seventy percent being domestically sourced.
The wind’s energy content depends on its speed, and it varies with elevation. This means that even small changes in wind speed have a big impact on the power available. Moreover, air density is affected by both temperature and elevation. Warm air is less dense than cold air, so wind turbines will produce more power when they are installed at lower altitudes. In addition, the turbines may cause harm to birds.
The installation of wind turbines depends on its design and specifications. The wind turbine installation includes the systems to capture wind energy, point the turbine into the wind, convert mechanical rotation into electrical power, and control it. This way, they are an excellent option for homes and businesses. In addition, wind turbines are becoming taller in recent years, which helps them take advantage of higher wind resources. However, there are drawbacks as well.