Paid PractitionerCertificate

Wind-Assisted Propulsion Engineering

What a rotor, wing, suction wing or kite is actually worth on a real ship: the aerodynamics that sets the force, the four penalties the hull and the engine take back out of it, and the route and compliance arithmetic that decides whether any of it is ever repaid.

Lessons
8
Quiz questions
72
Time
About 72 min
Price
€179+ VAT
Certificate
Graded final exam, then a PDF certificate with a number anyone can verify
Who it's for
Superintendents, naval architects, performance analysts and marine engineers assessing a wind-assist retrofit or newbuilding option: anyone who has been handed a saving expressed as one percentage and has to decide, on the evidence, whether to believe it.
Assumed knowledge
Trigonometry, and the propulsive chain at the level our course Naval Architecture for Performance teaches it: thrust, delivered power and a quasi-propulsive coefficient. Every calculation is worked on one ship in the text with its inputs and its answer shown, so a scientific calculator is enough. No CFD and no programming are assumed.
Taught by

Christos Papandreou

CEO & Founder, Blue Autonomy

  • Naval architect and marine engineer, National Technical University of Athens
  • 15 years of experience in fleet performance and operational data
  • Chief Scientific Officer, NEMO, previously DeepSea Technologies, StormGeo, Athenian Sea Carriers, PwC

Part of the Energy-Saving Devices in Depth specialisation.

What you will be able to do

By the end of the course. Each outcome names the lessons that deliver it, and the final exam samples every one of them.

  1. Resolve true wind and ship speed into the apparent wind speed and angle a device actually sees, reduce a measured wind between heights with the power law, and explain why a rated thrust means nothing without an apparent-wind angle attached. Lesson 1
  2. Resolve a device's lift and drag into the driving force that moves the ship and the side force she pays for it with, and convert driving force into engine kilowatts saved through the propulsive chain. Lesson 2
  3. Compute the induced drag and induced angle of attack a finite-span rig pays via lifting-line theory, explain why the aspect ratio a deck can accommodate dominates the answer, and judge whether a quoted drag coefficient belongs to a 2-D section or a real rig. Lesson 3
  4. Compare the wind-assist families on computed numbers rather than quoted ones: rigid wings and soft sails (sections, slots, feathering/reefing/stowing), the Flettner rotor (spin ratio, Magnus force, its own drive-power bill), and suction wings and kites (fan power, altitude and flight path). Rank them on force per area, parasitic power and stowability. Lessons 4, 5, 6
  5. Reduce a rig's gross aerodynamic thrust to a defensible net saving in brake power by sizing the heel, leeway, rudder and engine-load deductions, and state which of those deductions the published evidence actually supports. Lesson 7
  6. Weight a device's performance polar with route wind statistics into an annual saving, value the FuelEU Maritime wind reward factor beside it, and quote a payback with every assumption declared. Lesson 8

Fuel savings "as high as 30 per cent" are still quoted for wind assistance. For suction wings the figure goes back to the Cousteau turbosail programme of the 1980s: a demonstration project that envisaged 15 to 30 per cent for a merchant ship fitted with two turbosails and was abandoned when the oil price fell, beside one research vessel, Alcyone, for which we have found no comparative trial and no published account of the power her own fans drew. Independent route studies of wind devices on merchant ships mostly land well below that figure, and the gap between the two is not marketing. It is arithmetic we have not seen done.

This course does it. It starts where every wind-assist number has to start, with the apparent wind the device is actually immersed in rather than the wind the forecast gave, and follows one Panamax bulk carrier of about 75,000 tonnes deadweight all the way to a payback figure. In between: lift and drag resolved into the force that drives the ship and the force she pays for it with; lifting-line theory and why the aspect ratio a deck can accommodate is the most expensive constraint in the design; rigid wings, their sections, their slots and the difference between feathering, reefing and stowing; the Flettner rotor, its spin ratio and its electricity bill; suction wings and kites, ranked against the others on computed numbers rather than quoted ones; then the bill the ship presents in heel, leeway, rudder drag and an engine that does not enjoy being unloaded; and finally routing, the FuelEU Maritime wind reward factor, and who in a charter actually receives the saving.

The opening lesson, "The Velocity Triangle: Apparent Wind Is the Only Wind That Matters", is free to read as a sample. It is also the lesson everything else rests on, because a device's rated thrust means nothing without an apparent wind speed and angle attached to it, and the commonest error in the whole subject is made in its first line of trigonometry.

The course is honest about its evidence. The aerodynamics rests on standard theory and on published measurement where there is any, some of it from a single study, and where the course has had to assume a curve it says so. The penalties the hull takes back are engineering built around that, and they are quoted with the assumption stated and the answer given at more than one value of it.

By the end you should be able to take a supplier's performance polar, resolve it into driving and side force at the apparent wind angles your trade actually delivers, subtract the device's own consumption and the hull's penalties, weight the result with your route's wind statistics, and put a defensible annual figure and a payback beside the headline percentage. You should also be able to say, in one sentence each, which three numbers are missing from any wind-assist claim that arrives without them.

What the course covers

  1. The Velocity Triangle: Apparent Wind Is the Only Wind That Matters 8 min
  2. Lift, Drag, and the Two Forces That Result 9 min
  3. Lifting-Line Theory: Why Aspect Ratio Decides Everything 10 min
  4. Rigid Wings and Soft Sails: Sections, Slots and Reefing 9 min
  5. The Flettner Rotor: Magnus, Spin Ratio, and Its Own Power Bill 9 min
  6. Suction Wings and Kites 9 min
  7. What the Ship Pays: Heel, Leeway, Rudder and the Engine 9 min
  8. Routing, Reward Factors and the Value of a Sail 9 min

€179 + VAT

€221.96 including 24% VAT, which is what an individual in the EU pays. Outside the EU no VAT is added. A company in another EU country pays the net price once its VAT number is confirmed in VIES, the EU's register; a company in Greece pays the 24%. Checkout shows the total before you pay.

Paid once, for one person, for as long as the Academy runs: every lesson, the final examination and the certificate. This course has no Excel workbook, and is priced lower for it. Part of the Energy-Saving Devices in Depth specialisation, which costs less than its courses bought one at a time.

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All prices · Refunds: 7 days, unless you have started

Common questions

What exactly is included?

8 lessons (about 72 minutes in total), 72 quiz questions with explained answers.

How much does it cost?

€179 plus VAT, paid once: €221.96 with 24% VAT, which is what an individual in the EU pays; outside the EU no VAT is added, and a company in another EU country with a VAT number valid in VIES pays the net price. That buys every lesson, the final examination and the certificate, for one person, for as long as the Academy runs. This course has no Excel workbook: a course is priced mainly by how much teaching is in it, and one without a workbook costs less for it. The course is also part of the Energy-Saving Devices in Depth specialisation, which costs less than its courses bought one at a time. Everything else is on the pricing page.

Do I get a certificate?

Yes. The course ends with a graded final exam, marked on our server rather than in your browser: you see your score and which questions you got wrong, but not the answers, because the questions are drawn from a pool. Pass it and you get a PDF certificate in your name, with a certificate number on it.

That number is the point. Anyone you show the certificate to can check it themselves at academy.blueautonomy.gr/verify, with no account and no email to us: the page states the name, the course and the date we issued it. A certificate nobody can verify is a decorated PDF, and we would rather issue one that stands up.

Can I preview the course?

Yes: the first lesson, The Velocity Triangle: Apparent Wind Is the Only Wind That Matters, is free to read in full. It is a real lesson, not a trailer: same depth, same quiz.

Do I need prior knowledge?

Trigonometry, and the propulsive chain at the level our course Naval Architecture for Performance teaches it: thrust, delivered power and a quasi-propulsive coefficient. Every calculation is worked on one ship in the text with its inputs and its answer shown, so a scientific calculator is enough. No CFD and no programming are assumed.