Development, Bio diversity, Environment, Security and Disaster Management.
Conservation, environmental pollution and degradation, environmental impact assessment
Recently, PM dedicated three hydropower project to India.
800 MW hydropower station of NTPC- Koldam
412 MW Rampur Hydro Station of SJVNL projects
520 MW parvati project of NHPC
Implication to economy and environment
Himachal Pradesh has highest hydropower installed capacity in India. For hilly states like Himachal Pradesh, Uttarakhand, Kashmir, Sikkim and other north-eastern states, hydropower is important. They have specific place in the economy of the region. At the same time, it also provides electricity to national grid. Thus, these projects are important from that point of view.
These projects were commissioned in last couple of years. Also, these projects involve lot of cost. Economically, they cost Rs. 8-10 crores per MW. There are other costs too like environment costs, social costs, opportunity costs etc.
Energy crisis in India and hydropower projects
Significance of Hydropower
Hydropower is basically generating power from flowing water. There are few kinds of hydropower projects.
Run of the river hydropower projects– power is generated from flowing water. There is dam for each of hydropower project and from those dams, the water is diverted to tunnel which come backs to river few kms downstream. The head that the water gets between the points where it enters tunnel and where it exists, is used to generate power. This is run of river hydropower project.
On basis of capacity
> 25 MW = large hydropower
<25 MW = small hydropower
Below 2 MW = mini hydropower
There are also micro (5-10 KW) and pico (>5 KW) hydropower projects.
India has 42000 MW installed capacity of hydropower. It is 16% of installed capacity but the generation is low as it depends on availability of water. During drought, lean, summer season, when less water is available, then generation drops.
Issues related to hydropower
Two of three projects dedicated by PM is in Satluj basin. This basin has bumper to bumper hydropower projects like Karchum Wangtoo, Naptha Jhakri, Rampur, Luhri, Koldam, Bhakra on the same river. Hence, there are cumulative impacts.
Social impact– lot of people get displaced, livelihood resources get affected.
Environmental problems– most of the new projects are coming in Himalayan areas which is vulnerable to disasters in terms of earthquakes, landslides, floods, erosion. In the era of climate change, there is problem of glacial snow converting into rivers and thereby creating floods.
Significance of hydroelectricity when India is facing electricity surplus.
16% of installed hydropower total capacity is from hydropower. However, the generation from hydropower is 11-12%. And about 70% of the generation is during monsoon.
Hence there is a fluctuation. But one key benefit of hydropower is picking power. Picking power means the power supply in the grid. Demand is not constant- it grows during morning hours, declines during afternoon hours, goes up in evening hours and goes down at night. Together, there are seasonal variations and daily variations.
A thermal power project cannot be restarted when the demand goes up and shut down when there is less demand. That is possible with hydropower project. Because of the capacity with hydropower, it can generate more power during picking hours. However, this advantage is available only if it is optimises the operational hydropower project to provide maximum picking power. Other advantages of hydropower are clean, cheap, green source of energy. But these are debateable issues.
Sustainability of hydropower projects
Problems do exist with the hydropower project. Besides the social, environment and the disaster issues, there are also issues of generation performance. A study found that 89% of India’s installed capacity does not generate power at promised level. Each project, when it is given techno economic clearance, it is promises to generate power at 90% dependability, which means that in 90% of the year, it should be generating promised power. But when the actual performance is looked at over the last 30 years for all operating hydropower project, it was found that 89% of the projects generated electricity below the promised level. And half of them generated below 50% of the promised level.
Also, there is reduction in units generated by hydropower per million units every year. In last 20 years, per MW generation has gone down by 20%.
Also, there exists issues of siltation, maintenance of project, Repair, replacement and so on. This requires cost and if there is not proper allocation of cost for operational functions like maintenance, repair and replacement, then the electricity generation suffers.
When silt gathers in storage projects like Bhakra, Tehri, Sardar Sarovar, it reduces storage capacity and proportionally the power generation goes down.
So, these issues are important from the sustainability point of view.
So, having created the installed capacity of 42000 MW, there should be focus on optimising operation and generation from these projects. Only after it is achieved, new projects should be installed. This will assure better sustainability of benefit from the generation.
Carbon footprints and hydropower projects
It is assumed that as hydropower projects don’t consume fuel, they do not generate carbon footprints. The World Commission on Dams has shown how power, particularly in tropical countries, reservoirs also generate methane. One molecule of methane is 22 times potent GHG than C02. So there also needs to be assessment of carbon footprint.
Also, to make these projects, there is deforestation. Deforestation reduces carbon sink and thus there is addition of more carbon in atmosphere.
Water crisis like draught and low levels of water in river leads to closure of dams. Hydropower has to survive the intensity and frequency of droughts and more impacts of climate change. The rainfall pattern will change with larger gaps between two events and high when it occurs. This impacts the power generation capacity of hydropower projects.
If it is ensured that appraisal and impact assessment is proper, if the catchment is maintained properly, the hydropower projects can be sustainable. If the catchment is not maintained properly, then whatever rains come as flash floods, it damages the projects.
Constraints in hydropower projects
Huge costs is one of the constraints in developing hydropower. For this, it is necessary to optimise the generation from existing capacity. There is a need for proper environment impact assessment, including technical assessment. If 89% of hydropower projects are generating below promised level, then serious problem exists within appraisal of the project and method in which techno economic clearance is given.
So many projects have been developed in upstream that they are remaining empty. Also, India is using more groundwater. Hence, the surface water flow reduces in downstream area.
Every project is plagued by cost and time overruns problem. Even the recent three dedicated projects suffered from it and they also faced disaster during construction. The main reason is the imperfect appraisal of the project, whether technical, hydrological or geological.
Hydropower generates around 11-12% of India’s electricity capacity. Trajectory of renewable energy is going up. Today, solar and wind energy have overtaken hydropower in installed capacity. So, in future, sustainable benefits from existing hydropower should be used and then go for pico hydropower projects. Later, there should be proper appraisal and public consultation before more projects are involved.
Connecting the dots:
Can hydropower projects be called renewable energy projects? Examine the pros and cons of such projects with respect to other renewable projects of solar and wind energy.