Why in News?

• The crisis unfolding in Joshimath for over a month has led to conversations on the relevance of hydropower in the Himalayan region. Two years ago, a glacier burst led to question marks over the Rishiganga hydroelectric project in Uttarakhand.

What is hydropower?

• Hydropower generates electricity from the natural flow of water without releasing any emissions or pollutants. It also does not rely on fossil fuels. Therefore, it is often considered green energy.

Hydropower Projects in Himalayan region:

• The Himalaya are a major water source for much of South Asia: Most countries in the region, including India, China, Nepal, Bhutan, and Pakistan, have built or are planning to build hydropower projects in the Himalaya.
• Hydropower one of the key renewable energy sources of India: In India, the government has identified hydropower as a key renewable energy source. Many hydropower projects are under construction or in the planning stages in the Indian Himalaya, including the Subansiri Lower Hydroelectric Project in Arunachal Pradesh and the Teesta Low Dam Hydroelectric Project in Sikkim.
• Nepal has also identified hydropower as a major source of energy: Nepal has many hydropower projects in the planning and development stages, including the Arun III Hydroelectric Project and the West Seti Hydroelectric Project.
• Main source of revenue for Bhutan: In Bhutan, hydropower is the main source of revenue, and the government has set a target to export surplus electricity to India. The country has built several hydropower projects, including the Chukha Hydropower Project and the Tala Hydropower Project.

Concerns about the potential conflicts over water resources in the region:

• Fragile ecosystem of Himalaya already under stress: The Himalaya is a fragile ecosystem and home to a diverse range of flora and fauna. It is already threatened by deforestation, overgrazing, and construction activities that harm the environment and local communities that depend on it.
• Construction of dams can disrupt the characteristics of river flow: The construction of dams can disrupt the flow of rivers, leading to changes in water temperature and chemistry. It can also cause erosion, landslides, and sedimentation which can have a negative impact on the local environment.
• Construction disrupts well-being of the local population: Dams also disrupt the migration patterns of fish and other aquatic species and impact the local wildlife, particularly if the dam’s construction leads to habitat loss. Large-scale hydroelectric dams displace local communities, affecting their livelihoods and cultural heritage and impacting the overall well-being of the local population.

Micro hydro systems as an alternative to hydropower:

• Micro hydro system of 100 kilowatts (kW): It is a small-scale hydroelectric power generation system that typically generates up to 100 kilowatts (kW) of electricity.
• Applications: These systems use the energy of falling water to turn a turbine, which, in turn, generates electricity. They can be used for various applications, including powering homes, businesses, and small communities.
• Less expensive and smaller environmental footprint: They are typically less expensive to build and maintain than large hydroelectric dams and have a smaller environmental footprint.
• Can be located at inaccessible areas: They can be located even in inaccessible areas where it is difficult to transmit electricity from larger power stations, and they can provide a reliable source of energy to communities that are not connected to the grid.
• Two types : Micro hydro systems can be classified into two main types i.e., run-of-river and storage systems. 

1. Run-of-river systems use the natural flow of water in a stream or river to generate electricity. 
2. In contrast, storage systems use a reservoir to store water and release it as needed to generate electricity.

Conclusion:

• The environmental impact of hydropower can vary depending on projects and the ways in which they are implemented. Micro hydro systems can be tailored to minimize the ecosystem’s negative impact and provide sustainable energy solutions. However, it also can have some impact on the environment and local communities. A detailed assessment should be carried out to evaluate the potential impact before proceeding with the project.