Hydropower in India: Balancing global carbon benefits with local environmental costs
9th Mar, 2022
The large number of researchers criticizing the construction of hydro-projects in the Himalayan mountains highlight environmental damage imposed on local populations.
- It is hard to deny the benefits acquired from hydropower, however, the local environmental compromises cannot be dismissed.
- In 1947, hydropower capacity in India was about 37 percent of the total power generating capacity.
- In the late 1960s, growth in coal-based power generation initiated the decline in hydropower’s share in both capacity and generation.
- In 2022, hydropower capacity accounted for roughly 7 percent of total capacity.
What is Hydropower?
Hydro electricity is the conversion of the mechanical energy in flowing water into electricity. Hydro electricity is generated when the force of falling water from dams, rivers or waterfalls is used to turn turbines, which then drives generators that produce electricity. The energy produced is directed to a substation, where transformers "step up" the voltage before its transmission to the electricity grid.
Declining Growth in Power generation from Hydro Station in past:
- 1947-1967: Power generation from hydro stations grew by 11.8%
- 1967-1987: Power generation from hydro stations grew by 5.6%
- 1987-2007: Power generation from hydro stations grew by around 3%
- 2007-2019: Power generation from hydro stations grew by under 1%
- In 2020, hydropower contributed to 4,370 Terawatt-hours (TWh) of global electricity generation, the highest contribution by a renewable and low carbon energy resource.
- Reservoir-based hydropower projects also provide flood control and a dependable water supply for drinking and irrigation purposes.
- Many hydropower plants can ramp their electricity generation up and down very rapidly as compared with other power plants such as nuclear, coal, and natural gas.
- Hydropower plants can also be stopped and restarted relatively smoothly.
- This high degree of flexibility enables them to adjust quickly to shifts in demand and to compensate for fluctuations in supply from RE sources.
For Example: Hydropower demonstrated these capabilities on the 5th of April 2020 when most households in India switched off electrical lights for nine minutes. The anticipated electricity demand reduction was 12-14 GW but the actual demand loss was over 32 GW for 49 minutes, more than double the demand loss anticipated. Hydro generation stepped in increasing and then decreasing supply within few minutes.
Local Environmental costs:
- Twelve projects of total capacity of over 3,500 MW have either been terminated or held up due to local environmental concerns.
- Forty projects of capacity 13633 MW have either been abandoned or delayed due to local opposition to the projects rooted in local environmental concerns.
- In the last few years, many of India’s newer hydro-power projects on the Himalayan rivers have been damaged by floods and landslides. Though recurrent floods are a natural phenomenon, they can be aggravated by anthropogenic interventions.
- High precipitation in the Himalayas, coupled with the sudden fall in altitude in the mountains of that region results in large volume of water gushing down river channels.
- Construction of hydro projects and related infrastructure such as roads often aggravate this phenomenon.
Push for Hydropower:
In March 2019, the government approved targeted measures to promote hydropower development in India. This included
- Inclusion of large hydro power projects as RE sources.
- Hydro-purchase obligation (HPO) as a separate category in the non-solar renewable purchase obligation (RPO).
- Tariff rationalization measures including providing flexibility to the developers to determine tariff.
- Increasing debt repayment period to 18 years, and introduction of escalating tariff of 2 percent.
- Budgetary support for funding flood moderation component of hydropower projects on case-to-case basis for enabling infrastructure
- The hydropower generation is highly capital-intensive mode of electricity generation.
- Barring a few small projects in central and southern India, most are in the North and North-eastern states.
- This means reinvigoration of local agitations over environmental compromises.
- This is justified given that the massive flash floods in Uttarakhand in 2013 caused 5000 deaths, destroyed homes and damaged hydropower projects.
- The 12th plan cautioned that “hydro-power projects on the Himalayan Rivers may not be viable even if they are looked at from a narrow economic perspective”.
- The Himalayas are relatively young mountains with high rates of erosion. There is little vegetation in the upper catchment to bind soil.
- High sediment load reduces productive life of power stations through heavy siltation.
Local environmental concerns cannot be dismissed as environmental fundamentalism or anti-developmentalism. The trade-off between the local and global environmental benefits of hydropower are real. The costs are local, and the benefits are global and to some extent national.
It is important that the government policy, in its enthusiasm to contribute to the global public good of carbon reduction, does not ignore the cost imposed on the local environment and populations dependent on it.