Karandikars & Associates

Hydro Installed Capacity (GW)

Some of the key technology developments in water turbine manufacture occurred during the 19th century, and the developments spread across the globe

However the hydro power got the real boost with the developments in North America during the early decades of the 20th century, the most notable being construction of the Hoover and Grand Coulee dams in US, and with hydropower accounting for 40 per cent of the country’s electricity generation by 1940

From the 1940s to 1970s, spurred initially by World War II and followed by strong post-war economic and population growth, state-owned utilities built significant hydropower developments throughout Western Europe, as well as the Soviet Union, North America and Japan

Over the last decades of the twentieth century, Brazil, Canada and China became world leaders in hydropower

While discussing Renewables, both conventions are in vogue in literature, namely including hydropower in renewables and excluding hydropower and terming the balance category as "Non-Hydro" renewables

Both the conventions have their merits, depending upon the context in which they are used. We would only like to alert the readers on this difference and its implications while reading the literature

While Hydro electricity had been the major, rather the only utility commercial scale renewable resource till the beginning of the current century for electricity generation, Solar has already overtaken and Wind is soon expected to overtake hydro in installed capacity

Hydropower has certain key advantages, principle among them being the ability to start and stop quickly and instantaneous load acceptance/rejection. This makes it particularly suitable to meet peak demand and for enhancing system reliability and stability

The long life of the hydro power plants, the renewable nature of the energy source, very low operating and maintenance costs, absence of inflationary pressures experienced by the fossil fuels are some of the other advantages

On the other hand, hydroelectricity plants are highly capital intensive and the high initial cost has been one of the key barriers for its growth in most of the developing countries, where bulk of the untapped potential is located

Finally, although hydroelectricity is generally considered a clean energy source, it is not totally devoid of greenhouse gas emissions, ecosystem burdens and socio-economic adversities. As a result, many large-scale hydropower projects around the world are facing considerable environmental and social pressures and constraints in financial closure

For the year 2023, World conventional hydro installed capacity was 1,215.4 GW, that of India was 46.9 GW, that of China was 370.6 GW while that of US was 80.0 GW

Brazil (109.9 GW), Canada (83.1 GW), Japan (22.1 GW), Russia (51.4 GW), Turkey (31.6 GW) and Vietnam (21.9 GW) are the other countries which has significant hydro installed capacities

Our section Electricity from Hydro as a percent of total covers country-wise share of hydro in total electricity generation

View the trends graphically

Types of Hydro Power

The International Hydropower Association (IHA) categorizes hydropower into four main types: Storage (dams with reservoirs), Run-of-River (using natural river flow), Pumped Storage (energy storage by pumping water between reservoirs), and Offshore Hydropower

Storage: typically a large system that uses a dam to store water in a reservoir. Electricity is produced by releasing water from the reservoir through a turbine, which activates a generator. Storage hydropower provides base load as well as the ability to be shut down and started up at short notice according the demands of the system (peak load). It can offer enough storage capacity to operate independently of the hydrological inflow for many weeks or even months

Run-of-River: a facility that channels flowing water from a river through a canal or penstock to spin a turbine. Typically a run-of-river project will have little or no storage facility. Run-of-river provides a continuous supply of electricity (base load), with some flexibility of operation for daily fluctuations in demand through water flow that is regulated by the facility

Pumped-storage: provides peak-load supply, harnessing water which is cycled between a lower and upper reservoir by pumps which use surplus energy from the system at times of low demand. When electricity demand is high, water is released back to the lower reservoir through turbines to produce electricity

Offshore: a relative less established technology that uses tidal currents or the power of waves to generate electricity from seawater