ABSTRACT
When we left his office, we sat together-what to do now? We decided to find all the literature about the subject and find some people who knew something about windmills. And a few weeks
10.3 Important Fundamental RulesOur goal was to make the simplest possible windmill. We visited Risø, Gedser windmill, Tvind, Økær Vind Energi, Hjerm Elektro, Folkecenter, Kuriant, whose owner I knew, and many more. And when someone knew something about windmills-we listened avidly. Folkecenter had a complete concept for the production of a windmill. I asked if they could help us by making drawings and dimensioning for a windmill. The answer was no.Few days later I called Preben Maegaard and asked him for help with the major issues and about what we should watch out for. We would, of course, pay for these services. He answered “I cannot take a fee, but I am going to Copenhagen next week, then I can look in for a couple of hours.” During his visits we learnt about some important fundamental rules, such as don’t forget that • the main shaft should be of good quality and have a thickness of 10 mm for each rotor diameter • yawing should only be one degree a second • the gear must be twice as strong as the generator capacity • all other parts should be able to stand up to a permanent load of 120% • the shaft should be lined up in such a way that it puts a constant load on the yaw system 10.4 Quite a Good Thing to Be Little
BehindhandAt the outset there were only three persons: Stubkjær Sørensen; his wife Alice Sørensen, a draughtswoman; and me. We did things from the end backwards to the beginning, building the wind turbine piece by piece and made the drawings afterwards from what we had made. It was a hard time, as we had to hurry because Nordtank and Vestas were already marketing their wind turbines.When our prototype was ready, Risø came to inspect the wind turbine. I distinctly remember their remarks: this bearing house will slide, that plate will not stand for the axial loads, etc. Afterwards we set these things right, and upon their next visit they thought
installed our first wind turbine, we could not wait to know whether everything would be as we hoped. We were lucky. The wind turbine worked without any major problems. The first windmills were 22 kW, but we soon went on to 30 kW.In 1981, Danregn Vindkraft A/S was established as an independent enterprise. We were permanently behindhand and felt a strong pressure from our colleagues from other companies. When we were developing a 30 kW wind turbine, they were already at the 55 kW wind turbine. So the only thing was to develop a similar 55 kW wind turbine, and we succeeded comparatively rapidly. Looking back, it may not have been such a bad thing to be behindhand, because we escaped some of the mishaps that others ran into, I am thinking in particular of blade problems that Vestas
On 1 August 1981 we employed the first engineer. We also engaged a part-time consultant to assist us in the Californian market. The first six wind turbines were installed in California in December 1982.
