Energy plays a huge role in stabilizing and developing the world’s economy. It plays a pivotal role in all aspects of human welfare including agriculture, health care, employment, education and sustainability (Shakeel etal., 2016). The country’s economic development depends upon Energy. Every country needs energy sources to produce energy to fulfill economic requirements. Earth contains many energy sources, and they can divide into two groups and renewable and non-renewable. Non-renewable energy sources are the ones that collected from non-renewable energy source like fossil fuel. They include coal, gas, and oil, while renewable includes solar, hydro, and wind energy which they are collected by renewable sources. There is a huge demand for energy sources all over the world as the global energy consumption increase exponentially.
Current global energy consumption is recorded as 532 EJ (Exajoule). China is the number one energy consuming country in the world while USA holds the second place (Rashid, 2014). Between 1980 and 2006 the worldwide annual energy consumption increment has calculated as 2% growth rate. Accordingly, it is clear that the need of energy is unexplainable.
Primary energy sources are the ones that has not been converted or transformed into another forms, such as fossil fuels (oil, natural gas, coal, nuclear, solar, wind , hydro). Secondary energy such as electricity is produced from these primary energy sources. This study will focus on the efficiencies of wind and hydro power generation and compare effectiveness, advantages and disadvantages in each source.
It has been calculated that hydroelectric powerplants supply 16.4 % of the world’s electricity supply (Key World Energy Statics, 2012) and it is also expect, that this level will increase by 3% each year for the next 25 years. But at the same time, it is noted that the hydroelectric potential would be not enough to meet the future electricity demand.
Inherent benefits of hydropower
The natural source used in hydropower generation is water. It is widely spread geographically in most parts of the world. 150 of the countries have enough resources for hydropower generation. The technology behind this is well-known and proven with more than a century of experience. The efficiency of power generation in hydropower plant is about 90%, which is really a good value. The operating cost in a hydropower plant is relatively low compared to others enenthough the capital cost is relatively high. The lifespan of the power plant is also high in these. Hydropower can act in a multipurpose scheme because it can help to fund other important functions such as irrigation and water supply.
Present status of hydropower
Currently there are many hydropower plants are being constructing all around the world and the expecting power is more than 105000 MW . But the present development of hydro power generation in Australasia region (Australia and New Zealand) is relatively low compared to the other regions of the world. Here in Australia, they have installed 7501 MW capacity while in New Zealand it is around 5082 MW (Bartle, 2002).
Figure 1: Structural diagram of hydropower generation system (Extracted from (Chen etal., 2018))
Wind power is another important player in world’s energy market. It has number of benefits an advantages compared to other traditional energy sources. Wind power generation is clean and environmentally friendly. Because fossil fuel combustion releases harmful gases and nuclear power generation produce radioactive waste matters. The available wind power that can be converted to electricity is approximately 1.26 × 109 MW. Not like hydropower, it has found that wind energy in principle could meet the entire energy need of the world.
Wind power Generation
A wind is produced as a result of the movement of air in the atmosphere due to a pressure gradient where from regions of high pressure to low pressure. Wind speed is directly propotional to the magnitude of the pressure gradient. The generation and the movement of wind also affected by uneven solar heating, Coriolis effect and other local geographical conditions.
Wind energy is a special type of kinetic energy and it can be converted either into electricity or the energy can be directly used to operate pumping machines, sailing or shipping (Golding and Harris, 1976).
Figure 2 General desing of a wind power plant (Extracted from https://www.onecommunityglobal.org/wind-energy-setup-maintenance/)
Environmental Impacts of wind and hydro power generation
It has been recorded that annually there are about 328000 birds in North Amarica die because of wind turbines. This is a /considerable wildlife impact. Wind turbines and construction of wind plants can potentially degrade the wildlife habitat (Sun etal., 2008). Hydro power generation also create impacts to the environment. Creation of large reservoirs in the areas that used to be a wildlife habitat is one of the biggest impact associate with hydropower generation. Also it can affect endemic and non endemic fish species (Chen etal.,2015).
Wind Energy Vs. Hydro Energy
Both of these energy technologies have their own benefits and challenges. Compared to the wind energy, hydropower generation is nor reliable in the coming years. Availability of water is demanding for many parts of the world. Expanding the hydropower creates a much environmental impact compared to the wind power generation. Offshore winds and inshore winds has much potential compared to the hydro power generation due to its availability all around the world. Thus, wind power generation is much more environmental friendly and reliable.
According to previous studies, investment of $17 million in wind power has resulted in annual generation of 21.9 MWH energy while the same amount of investment produce only 10.9 MWH energy in hydropower (Cost Efficiency of Hydropower vs. Wind Power in the Context of the Fate of the Boardman River Dams, 2008). It is thus clear that investing on wind power is much more effective than investing on hydropower.
Bartle, A., 2002. Hydropower potential and development activities. Energy policy, 30(14), pp.1231-1239.
Chen, S., Chen, B. and Fath, B.D., 2015. Assessing the cumulative environmental impact of hydropower construction on river systems based on energy network model. Renewable and Sustainable Energy Reviews, 42, pp.78-92.
Golding, E.W. and Harris, R.I., 1976. The generation of electricity by wind power (pp. 153-154). London: E. & FN Spon.
Key World Energy Statistics 2012, Annual Technical Report of the International EnergyAgency
Li, H., Chen, D., Gao, X., Wang, X., Han, Q. and Wu, C., 2018. Fast-slow dynamics of a hydropower generation system with multi-time scales. Mechanical Systems and Signal Processing, 110, pp.458-468.
Rashid, M.H. ed., 2014. Alternative energy in power electronics. Butterworth-Heinemann.
Shakeel, S.R., Takala, J. and Shakeel, W., 2016. Renewable energy sources in power generation in Pakistan. Renewable and Sustainable Energy Reviews, 64, pp.421-434.
Sun, C.S., Wang, Y.N., Li, X.R. and Ma, S.Y., 2008. Environmental impact of wind power generation projects. J. Electr. Power Sci. Technol, 23, pp.19-23.
Cost Efficiency of Hydropower vs. Wind Power in the Context of the Fate of the Boardman River Dams-2008 (https://www.gtbay.org/wp-content/uploads/2010/10/Hydro-vs-Wind.pdf) Sited on 5th Nov 2020.
https://www.onecommunityglobal.org/wind-energy-setup-maintenance/ (Sited on 5th November 2020)