Growian is a compression of Große Windenergieanlage — large wind energy installation — and the name is the whole design philosophy. The rotor spanned 100.4 metres and turned at roughly 19.5 revolutions per minute on a hub 100 metres up. Rated output was 3,000 kilowatts, the highest in the world at the time. The machine house alone weighed 340 tonnes, sitting on a tower reaching 96.6 metres, and each of the two blades weighed 23 tonnes. MAN led the engineering. On paper the numbers were reasonable: cut in at 5.4 metres per second, rated at 12, shut down at 24, survive 60, and produce something like 12 gigawatt-hours a year at a mean wind speed of 9.3 metres per second. This was a leap of an order of magnitude past anything then operating. Almost nothing about the installation had been tested at that scale before.

Two blades, not three. And the rotor mounted downwind of the tower rather than upwind — a lee runner, in the German phrase — so that each blade passed through the tower's wind shadow once per revolution and got hit with a sudden load drop and recovery. To absorb that, the designers gave the hub a teetering joint, letting the rotor rock. The blades' pitch was regulated by a mechanical-electrical mechanism. The combination proved unmanageable. Faults in the machine house casing meant the turbine could never be run at full output, and materials and construction problems interrupted testing constantly. In 1984 a bearing failed; the repair cost ten million deutschmarks. The scale that made Growian impressive also made every load, every vibration and every crack larger than anyone's experience could account for.

The first test run came on 6 July 1983, with official commissioning on 4 October. Between then and the end of operations in August 1987, the machine spent the overwhelming majority of its life standing still. Add up every hour the rotor actually turned under load and it comes to around 420 — roughly two and a half weeks, spread across four years. Decommissioning ran through 1987, and the turbine was dismantled in the summer of 1988. It never came close to the 12 gigawatt-hours a year its designers had projected. As an experiment it did return data, mostly of the kind that tells you what not to do.

The uncomfortable part of the Growian story is that failure was not universally unwelcome. Overall and technical direction rested with the utility HEW, commercial management with Schleswag, and the federal research ministry paid. Some of the partners were, at best, ambivalent. Günther Klätte, a board member at the utility RWE, told a general business meeting that they required Growian as a proof of failure of concept, and described it as a kind of pedagogical tool to convert the anti-nuclear energy crowd to the true faith. Hans Matthöfer, then finance minister and previously research minister, was quoted in similar terms: they knew it would do nothing for them, but they were doing it to demonstrate to wind energy advocates that it did not work. A machine designed by committee, funded by people with opposing goals, and contractually promised to the scrapyard from the beginning did not have much chance.

The koog did not stay empty. In 1988, the year after Growian shut down for good, Germany's first wind farm opened on the same reclaimed polder: the Windenergiepark Westküste, thirty turbines producing around 19 million kilowatt-hours a year. They were small machines, individually unimpressive, and collectively they worked. That is the lesson the site now teaches, and it teaches it by contrast — Kaiser-Wilhelm-Koog is a village of a few hundred people that calls itself the root of German wind energy, and it earned the title twice, once by building the wrong thing at enormous expense and once by building the right thing immediately afterward. The turbines standing there today are descendants of the second idea.