As old as civilizations everywhere
Water power has been harnessed since ancient times and in many civilizations around the world. It was used primarily in water mills to grind grain into flour and also later to power equipment like trip hammers, looms to weave cloth or saws to cut timber or other materials.
Water power was superseded by steam power, which became one of the main drivers of the industrial revolution in the late 18th century. Water power was to find a new life when it was discovered that it could be used to produce electricity.
First hydroelectric project brainchild of a bright spark
The world’s first hydroelectric project was the brainchild of English inventor and industrialist Lord Armstrong. He harnessed water power from lakes on his Cragside estate in Northumberland, England, to generate electricity through a turbine to power a single light bulb in his country house in 1878.
Within 2-3 years a number of small hydropower plants were installed in the US and Canada to provide electricity to local private and commercial customers for lighting and to power machines, in particular in mills.
The world's first hydroelectric plant started operating in 1882 in Appleton, Wisconsin (US).
The first large-scale hydroelectric plant in the world, the Adams power plant in Niagara Falls, New York State, was built in 1895. Its original Westinghouse generators remained in operation in the transformer house until the plant closed in 1961.
Within a decade of the first hydropower plant being launched, hundreds of others were in operation, first in North America, then in Europe in the 1890s and in Asia in the early 1900s (Taipei, 1905, Shilongba, mainland China, 1912, still in operation).
During the first half of the 19th century hydropower became the world’s most important source of electricity.
The expansion of hydropower was made possible by the development of three different types of turbines, which are still the ones in use today.
In 1849 British-American engineer James Francis developed the Francis turbine, a reaction water turbine that is still the most widely-used water turbine today.
In 1880 American inventor Lester Allan Pelton patented his Pelton water wheel, an impulse water turbine, which he had been developing over the previous decade.
In 1912-1913 Austrian engineer Viktor Kaplan invented the Kaplan turbine – a propeller-type turbine with adjustable blades.
Standardization soon emerging as essential
As hydropower expanded rapidly around the world the IEC took the lead on standardization work for hydropower installations.
A short paragraph in the report of the IEC Meeting held in Turin, Italy, in September 1911, marked the first steps of IEC involvement in standardization for hydropower.
It reads: "On the proposition of the Italian Committee, the Special Committee [on the rating of electrical machinery and apparatus] expressed the desire that the Central Office should organise a Special Committee (7 members) to co-operate with the Italian Committee in the study of certain questions relating to hydraulic and mechanical installations in connection with electrical plants. This Committee may include members who are not necessarily members of the IEC." (IEC Publication No 12)
Delegates from the Austrian, British, French, German, Italian, Norwegian, Swiss and US Committees attending a meeting of the "Special Committee on Prime Movers in connection with Electrical Plant", in Zürich, Switzerland, in January 1913, finalized the first standardization measures for hydropower installations.
A résumé of this meeting (IEC Publication No 21) lists the following decisions approved at the meeting:
- The adoption of the kilowatt as "the industrial unit of mechanical power"
- Definitions relating to hydroelectric installations concerning flow and discharge, hydraulic head (height of water), energy and power, turbines (hydraulic input, rated mechanical output and load speed, maximum output and efficiency).
- Adoption of other technical parameters.
Of particular interests in this document are three diagrams "showing the various heads" for closed and open Francis turbines, and for a Pelton wheel (Kaplan turbines had not been deployed yet in hydropower installations at the time).
These January 1913 IEC proposals are still at the centre of hydroelectric power standardization. IEC Technical Committee (TC) 4: Hydraulic turbines, continues this work and although many of its Standards are well established, it keeps maintaining and updating them as well as developing new ones, in particular for plant automation and issues linked to hydro-abrasion and erosion.
Mature technology with a bright future
More than 130 years after the first hydropower plant started producing electricity, hydroelectricity is still expanding in many parts of the world. It is set to play an important role in the future global energy mix as the world moves away from fossil fuels and nuclear energy to adopt more REs.
Hydropower presents a major advantage over other RE sources: it is not intermittent like solar photovoltaic or wind power and can be brought on line nearly instantly.
If they need large investments due to the large scale of the civil engineering work they require, hydropower installations, which rest on a mature technology, can last for many decades if properly operated, maintained and upgraded. This can be observed in installations like the Shilongba plant, in mainland China, which went live in 1912 and is still in operation, or the Beauharnois power station, in the Canadian province of Québec, the first units of which went on line 83 years ago.
Investments in hydropower are set to continue for the foreseeable future. The International Energy Agency (IEA) 2014 World Energy Outlook forecasts that USD 1 900 billion will be invested in hydropower between 2014 and 2040, the second largest investment in RE installations.
The IEA forecasts that 853 GW of hydropower capacity will be added and 152 GW of capacity will be retired over the same period.
It notes also that "the share of hydropower in total renewables-based output decreases from more than 75% today to less than 50% in 2040".
The slowing down of the rate of expansion of hydropower over time is the result of diminishing opportunities to install new large-scale dams, according to the IEA.