Hydroelectric Dams have disadvantages which are quite different from those of other forms of renewable energy like solar, wind, geothermal or nuclear energy. Hydro Power in small sizes which is constructed keeping nature in mind has almost no drawbacks, however the big Hydro Power Dams have some sizable problems. Some of these are tail risks […]

Hydroelectricity is the production of electrical power through the use of the gravitational force of falling or flowing water.Hydroelectricity capacity is around 800 GW accounting for almost 20% of the global electricity capcity.China and Canada have the largest hydro capacities in the world.If you consider Hydropower as renewable energy,then Hydro is the most widely used renewable energy in the world.In fact Hydroelectricity is the 3rd biggest source of electricity in the world after coal and oil/gas.Hydroelectricity power plants can have massive capacities with the Three Gorges Dam in China being the world’s largest at 22.5 GW.The Itiapu and Guri Dams in South America are the 2nd and 3rd largest with 14 GW and 10 GW capacities.China is set to double its massive hydroelectric capacity to almost 400 GW by 2020 from 20 GW currently.The advantages of Hydroelectricity are many

Alternative Energy in India saw significant growth in 2010 with the last 9 months of the year seeing capacity additions of 1800 MW which is almost 10% of the total installed capacity of 18500 MW.The growth in renewable energy was led by Wind Energy which forms almost 70% of the total renewable energy capacity in the country at around 13500 MW.The strong incentives given by both state and central government has led to the sharp growth of wind energy.Note Wind Energy is quite close to Gas based electricity price.India Needs at least 68 GW of Renewable Energy Capacity by 2020 to meet its RPS target of 15% set by CERC (note this is capacity only not hours of electricity).

China has the world’s largest hydro power capacity at 200 GW and it plans to double the capacity by 2020.China is mostly dependent on Coal Power and Hydro Power to meet the electricity demand from its fast growing economy.China has the world’s second largest electricity capacity at 850-900 GW second only to USA at ~1000 GW.This will be soon be overtaken as China continues to grow at 8-10% and its electricity per capita is still much below developed world standards.China is already the world’s biggest consumer of Energy and emitter of Greenhouse Gases.Despite rapidly investing in Nuclear and Renewable Energy,China’s voracious demand has made the growth of Fossil Fuel Energy unsustainable.It already consumes 3 Billion Tons of Coal per year and is already importing around 180 million tons per year.

India has set up ambitious targets of meeting 15% of its Energy Needs from Renewable Sources up from around 5.5-6% in 2010.WIth India’s Electricity Capacity expected to rise to 450 GW from around 165 GW,this would imply that around 67.5 GW of Electricity Capacity would be needed up from around 16 GW.This would mean around 5 GW of Capacity addition every year in the next decade which is a very tall order.20 GW could be met by Solar Energy according to the Jawaharlal Nehru Solar Mission (JNNSM).Most of the rest would have to met by Wind Energy.Biomass Energy has high costs and reliability problems which mini hydro potential is only 1 GW.Note this is just the capacity I am talking about,for meeting the electricity generation,capacity additions would have to be greater as Solar Energy and Wind Energy have only 20-30% Load Factor compared to 60-80% for Fossil Fuel Energy Sources.Nuclear Energy can contribute another 20 GW.
Renewable Energy in India is growing at a rapid pace increasing its share of the total capacity from 2% in 2003 to around 10% in 2010.However the share of electricity generation is still quite low at 3% due to the lower capacity load factors of Green Energy Sources compared to Fossil Fuel Sources.The Total Installed Capacity of Renewable Energy in India is around 16 GW with Wind Energy taking the Lion’s share at almost 70% followed by Small Hydro at 15% and Biomass Energy at 12%.Solar Energy in India till now has a capacity of just 6 MW which is estimated to grow to 22 GW by 2022 making Solar Energy one of the Biggest Growth Opportunities in the Field of Indian Energy.

Earthquake Vulnerability – Large Dam Construction has been linked to increased propensity of Earthquakes.Massive Earthquakes in China and Uttarakhand in India were linked to the building of Massive Dams in these countries.Building of Massive Man Made Structures along geologically sensitive areas has not been properly studied and understood till now

Summary

While Hydro Power is a necessity for an energy starved and growing economy like India,its effect have to be properly assessed and understood before going on a hydro binge.NTPC lost almost $300 million after its 600 MW project was canceled 5 years after getting permission.This was done in the face of large scale protest by local groups and NGOs.2 other projects in Uttarkhand have also been rejected leading to more losses.