The case for hydropower
IN the 19th Century much of the electric power in the Industrial and developing countries was generated with the burning of fossil fuels and hydropower.
Later on, around the middle of the 20th Century focus turned towards solar, wind and nuclear power. Development of nuclear power became more dominant in the Industrial world.
However, staunch resistance to nuclear energy nurtured mainly by the potential hazards associated with the leakage of the nuclear radiation and the dumping of the nuclear waste, the developed nations in Europe and Japan shifted focus towards renewable energy resources.
Similarly coal was widely used to generate electricity but due to grave problems posed by the carbon emissions, coal plants were abandoned or converted to other fuels.
It is now widely available for commercial and domestic markets. Other common fuels utilized are diesel and natural gas.
These fuels are becoming scarcer, expensive and posing climatic problems mainly with their carbon emissions.
Further they have sustainability issues related to the availability and higher costs. Therefore the recent trend is inclining towards diverting the generation of electrical power with renewable energies, mainly solar, wind and water.
The successes in the development of photovoltaic technology in terms of increased efficiency and reduced costs, led solar energy to the forefront.
At the same time countries endowed with abundant water resources harnessed water effectively for the generation of electrical power.
Hydropower has the added advantage that not only it generates substantial electric power it is also a great source of water storage.
Therefore it is a viable alternative next to wind and solar specially for the countries with great river runs and gorges for water storage.
Here we will discuss the pros and cons of hydroelectric power. Since ancient times rivers were harnessed to utilize the power of water into generating energy.
It is reported that the first water mills were in operation in c 80 BC. First commercial hydropower plant was in operation in 1882.
In the present times although the cost of solar has come down drastically, hydropower still remains the cheapest source of electric energy.
Countries which have vast resources of water have harnessed the river successfully for power generation and water storage.
For example, the South American countries are producing more than half of their total production from hydropower.
Some countries like Norway are generating 100% of their electric power from renewables including hydropower.
The added advantage of generation of electric power with hydropower is the storage of water.
Water is vital to life. It’s becoming scarcer with passage of every year due to climate change. Millions of cubic water is lost to the seas, especially during the rainy seasons.
River beds are drying up during the low ice melting and dry seasons. Therefore it becomes imperative to store water by constructing dams.
The stored water can thus be utilized not only to generate the electric power but also to supply water in the river downstream during the low rainy and winter season.
Thus averting the onslaught of drought by supplying fresh water for agriculture, rural and urban daily utilization.
Besides, a dam has a great advantage of controlling the floods by storing excess flood water in its reservoir during the flood season.
The major argument against the dams is raised that some major areas upstream the dam would be inundated while the river downstream will become parched.
Further the population resident at the reservoir site has to be relocated to higher grounds.
The dam area also gets affected ecologically as it involves the annihilation of the birds and wild animal life.
Both the human, birds and wildlife along with precious plantations have to be rehabilitated at safer grounds before taking up the constructional activities.
Secondly, care has to be taken to protect the archaeological sites and if required should be shifted to safer grounds.
However these issues can be successfully tackled with rightful planning and execution. The dams therefore play a major role to alleviate acute irrigation requirements while substantially contributing to reducing intensity, quantum and duration of floods avoiding destruction of crops and inundation of homes.
Dams contribute greatly to all sectors of economy by accelerating development and creating job opportunities by making electricity available to agricultural and industrial sectors.
—To be continued.
—The writer is an Engineer, based in Islamabad.
