How it began
Viktor Kaplan was born in Mürzzuschlag, Austria, in 1876 and moved to Brno in 1903 to join the German Technical University. There he studied how to use water flows more economically. In 1909 he was allowed to set up a laboratory in the basement of the school, which he had to equip largely himself. He obtained his first patent for a propeller turbine with adjustable blades in 1912, and between 1912 and 1914 he applied for patents on his main inventions. The Brno businessman Heinrich Storek backed the research.
Before it existed
Electricity from water was generated with Francis and Pelton turbines. By the early 20th century these no longer met the needs of industry, and the Francis turbine could not produce power efficiently where the drop of water was low. Kaplan started from Francis's design and looked for the best parameters, and he was the first to take the viscosity of water into account in his calculations.
How it works
Kaplan reduced the number of runner blades and found that an efficient turbine should work much like a ship's propeller. He mounted the blades so that their angle could be changed, which adapts the runner to the amount of water flowing at the moment. Automatically adjusted blades are combined with automatically adjusted wicket gates. The turbine stays efficient over a wide range of flow and water level, so variable rivers can still be used profitably.
How it spread
The Brno company Ignaz Storek built the first Kaplan turbine in 1919. It was installed at a spinning mill in Velm, Austria, reached 86 percent efficiency and ran for 33 years. A demonstration unit was also installed in Poděbrady. In 1925 an 8,243 kilowatt turbine with a 5.8 meter runner, then the largest in the world, went into the Lilla Edet power plant in Sweden. Storek made more than 500 turbines for many European countries.
Who pushed back
It took nearly a decade for the patents to be recognized. World War I slowed the process, but the main obstacle was the makers of Francis turbines, who saw the invention as a threat to their investments. Attacks on his reputation led Kaplan to a nervous breakdown before the patent process was completed in 1920. In 1922 blades broke on large rivers because of cavitation, a problem his assistants helped to solve.
Where it stands today
Kaplan turbines are widely used throughout the world for power production at sites with a low head and a high flow. Runner diameters range from 2 to 11 meters. The Technical Museum in Brno displays a Kaplan turbine, a memorial to Kaplan and parts of the experimental equipment he used.
