Lecture: Prof. Dr. Moritz Diehl
Tutor: Nick Harder
The aim of this lecture course (6 ECTS) is that students understand the physical principles of wind energy and the technology of modern wind energy systems. It consists of lectures and exercises, and is given by Prof. Dr. Moritz Diehl and Nick Harder.
Contents:
 global wind energy resource
 aerodynamic principles of wind turbines
 design of modern wind turbines
 control of modern wind turbines
 the electrical system of wind turbines
 alternative concepts and airborne wind energy
Course Organization
The course is organized as flipped classroom. We provide recordings of the lectures and will meet once every week for either a Q&A or an exercise session. The detailed time plan for the semester can be found below. We highly recommend to follow the suggesed schedule for the lectures.
Sessions: We will meet every Thursday, 2:00 PM to 3:30 PM in the Building 101, Room HS026. These meetings are alternatingly dedicated to either Q&A sessions with Prof. Diehl or exercise sessions with Nick Harder. For a detailed plan see the table below.
Lecture recordings: The lecture recordings were already created in a past semester.
Course manuscript: The lectures are accompanied by a detailed course manuscript, which you may find here.
Q&A sessions: Every second week there will be a virtual Q&A session with Prof. Diehl, where you can ask any questions about the course content. The format is meant to be highly interactive and depends strongly on your participation. We would recommend that while watching the video lectures or reading the course script, you write down any questions that come to your mind, such that you have them readily available for the Q&A sessions.
Exercises: The exercises are voluntary (though of course we strongly recommend to solve them). Nonetheless we offer the possibility to hand them in to receive feedback, but for this please respect the deadlines you can find in the calendar below. If you would like feedback on a specific part of the exercise especially, you can state so on your solution sheet. To hand them in, send them in an email to: nick.harder@inatech.unifreiburg.de.
Final evaluation: The final exam is a written exam. This final exam is 'closedbook,' which means that ONLY pens, a calculator, and one A4 page (that is, two sides) of notes can be used. The questions will be partially multiplechoice and partially shortanswer.
Schedule
When 
Content 
Recordings 
Week 1 10.04  14.04 
Chapter 1: Introduction Section 1.1: Introduction (Slides) Section 1.2: Energy content of the wind 

13.04 2:00 PM 
No session 

Week 2 17.04  21.04 
Section 1.3: Power density of blade area Section 1.4: Components of modern wind turbine Section 1.5: Blade & Airfoil nomenclature 

20.04 2:00 PM 
Introduction session 

Week 3 24.04  28.04 
Chapter 2: The Wind Resource Section 2.1: Origins Section 2.2: Global patterns Section 2.3: Mechanics of wind
Exercise Sheet 1 

27.04 2:00 PM 
Exercise session 

Week 4 01.05  05.05 
Section 2.4: Stable and unstable atmospheric stratification Section 2.5: Statistics of wind Section 2.6: Spectral properties of wind
Exercise Sheet 2 

04.05 2:00 PM 
Exercise session / Q&A session 

Week 5 08.05  12.05 
Chapter 3: Aerodynamics of Wind Turbines Section 3.1: Wakes Section 3.2: Actuator disc model and the Betz' limit
Exercise Sheet 3 

11.05 2:00 PM 
Q&A session 

Week 6 15.05  19.05 
Section 3.3: Wake rotation & rotor disc theory Section 3.4: Blade element momentum (BEM) theory 

18.05 2:00 PM 
Holiday (no session) 

Week 7 22.05  26.05 
Section 3.4: Blade element momentum (BEM) theory 

25.05 12:30 PM 
Hike to wind turbines on Rosskopf 

Week 8 29.05  02.06 
Holidays  
01.06 2:00 PM 
Holiday (no session) 

Week 9 05.06  09.06 
Section 3.4: Blade element momentum (BEM) theory
Exercise Sheet 4 

08.06 2:00 PM 
Holiday (no session) 

Week 10 12.06  16.06 
Chapter 4: Mechanics & Dynamics of Wind Turbines Section 4.1: Steady loads in normal operation Section 4.2: Stress and strain Section 4.3: Static beam bending 

15.06 2:00 PM 
Exercise session 

Week 11 19.06  23.06 
Section 4.4.1: Intro: springmassdamper system Section 4.4.2: Eigenmodes Section 4.4.3: Rayleighs method 

22.06 2:00 PM 
Q&A session 

Week 12 26.06  30.06 
Section 4.4.4: Dynamic beam equation Section 4.4.5: Tower eigenmodes Section 4.4.6: Stiff & soft towers Section 4.5: Blade oscillation & centrifugal stiffening
Exercise Sheet 5 

29.06 2:00 PM 
Exercise session 

Week 13 03.07  07.07 
Chapter 5: Control of Wind Turbines Section 5.1: Sensors and Actuators in wind turbines Section 5.2: Control system architecture Section 5.3: Control of variable speed turbines
Practice exam 

06.07 2:00 PM 
Q&A session / Guest Talk by Prof. Dr. Jens Geisler 

Week 14 10.07  14.07 
Section 5.4: Torque control at subrated power
Section 5.5: Thrust jump at nominal wind speed 

13.07 2:00 PM 
Exercise session 

Week 15 17.07  21.07 
Chapter 6: Alternative Concepts Section 6.1: Vertical axes wind turbines Section 6.2: Airborne Wind Turbines 

20.07 2:00 PM 
Summary session 

11.09 9:0012:00 
FINAL EXAM 
Special Events

The tour to the wind turbines on Rosskopf will take place on May 25th, 2023, in the afternoon. We will start from Kanonenplatz at 12:30, the excursion at the wind turbines will be from 14:00 till 15:00. We will meet with Andreas Markowsky and Thomas Schuwald, the managing directors of Ökostromgruppe Freiburg (the company operating the wind turbines), who give technical and administrative details on the turbines. Afterwards we will head back and you can expect to be back in Freiburg at around 17:30.

On July 6th at 14:00 we will have an invited guest in the lecture room, Prof. Dr.Ing. Jens Geisler, Hochschule Flensburg University of Applied Sciences, who will give a guest lecture on the industrial practice of wind turbine control.
Resources
Wind Energy Handbook is available here.
Wind Energy Explained: Theory, Design and Application is available here. This book should be your number one reference if you don't understanding something from the handbook.
Links of interest
20200512 Report on renewable power generation costs in 2018 (by IRENA) (PDF)
20200519 Which way a wind turbine turns might not seem to matter (by the Economist) (screenshot)
20200519 Atmospheric circulation patterns (from wikipedia)
20200526 Article on the Global Energy Transition (by the Economist)
20200602 Albert Betz: WindEnergie. Cover, Turbine Illustrations, Concluding Sentence