How it began
Poul la Cour, a physicist and teacher at Askov Folk High School, believed that wind should contribute to the electrification of Denmark. In 1891 he had the idea of storing wind energy as hydrogen and oxygen by passing the electricity through water. The Danish government gave financial support, and the first experimental mill at Askov was erected in the summer of 1891. A larger mill followed in 1897.
Before it existed
In the Netherlands the idea of electrification by windmills had been examined and rejected because of low efficiency and the difficulty of storing the energy. Electricity was only then being introduced in Denmark, and its conveniences were found in the cities, not in the countryside.
How it works
The mill drove a generator. To get constant power from gusty wind, la Cour devised the Kratostat, a differential regulator. The electricity split water by electrolysis, and the hydrogen and oxygen were kept in tanks, including a 12 cubic meter hydrogen tank. From 1895 to 1902 the school was lit by burning the gas mixture, reportedly without a day lacking light. Batteries and a gasoline engine for reserve power were used later.
How it spread
In 1902 the Askov mill became a prototype power plant that served the village until 1958. In 1903 la Cour founded the Danish Wind Electricity Society, which in the next five years planned about a hundred small power plants, a third of them wind powered, and trained some 20 wind electricians a year at Askov. The regulator was widely used in wind mills in the Nordic countries and Germany.
Who pushed back
Because the Askov mill looked like a traditional Dutch windmill, many people criticized the work, and the government reduced its support in 1902. Later, large coal-fired stations and the change to alternating current halted the spread of wind electricity, and over the next 50 years it shrank to small local operations.
Where it stands today
Johannes Juul, a former student of the Askov courses, built a successful experimental wind turbine in 1957 that became the starting point for Danish wind work in the 1970s. By 2002 nearly 20 percent of Denmark's electricity consumption came from wind. The buildings at Askov now house the Poul la Cour Museum.
