The Energy Efficiency Design Index (EEDI) Stefan Krüger TU Hamburg- Harburg Institute of ship design and ship safety - PDF

Description
The Energy Efficiency Design Index (EEDI) Stefan Krüger TU Hamburg- Harburg Institute of ship design and ship safety Motivation for EEDI CO 2 -Output from shipping is expected to increase not tolerated

Please download to get full document.

View again

of 15
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Information
Category:

Journals

Publish on:

Views: 159 | Pages: 15

Extension: PDF | Download: 0

Share
Transcript
The Energy Efficiency Design Index (EEDI) Stefan Krüger TU Hamburg- Harburg Institute of ship design and ship safety Motivation for EEDI CO 2 -Output from shipping is expected to increase not tolerated by society CO 2 -Output is proportional to fuel consumption (matter of fact) All measures to decrease fuel consumption also decrease CO2- footprint. Fuel efficient ships are accepted by the market if fuel price is high enough (was not the case in the past) CO 2 - problem could most efficiently be solved by adjusting the fuel price accordingly (MBI). IMO is responsible for CO 2 -reduction in shipping. IMO does not favour MBIs, but creates an index (EEDI) Principles of EEDI (1) The EEDI expresses the impact to environment from shipping versus the benefit to society from shipping Impact to environment Power*SFOC* f co2 EEDI = = Benefit to society Deadweight *speed EEDI is measured in gco 2 per ton mile. Concept is roughly reasonable, if deadweight would be replaced by payload. How much EEDI is acceptable? Now, political aspects enter the playing field. Principles of EEDI (2) The acceptable EEDI (base line definition) depends solely on the deadweight of the ship and the ship type. Baseline = F(DW). A ship is seen as efficient if it is slow and big. (Engineers have a different view on this). The base lines are devloped from regressions over existing data bases (FAIRPLAY). A newbuilding then must have an EEDI below the prescribed baseline. Baseline Example for RoRo-Ships The data shows significant scatter! All ships above the base line will be excluded from the market. Data Problems Ship Description in Data-Bases: (LR, ShipPax, etc.) Correct data from model test report: Deadweight: from 9050 t to t Speed : from kn to kn Power : kw (2 MaK 9 M 43) Power : kw kw Speed : kn kn Deadweight : 7663 t t Draft : 5.70 m (Design) 7.40 m (Full Scantling) Conclusion: Only consistent data should be used for EEDI-trials!! (Extremely important for smaller ships!!) TUHH- Evaluation Procedure The EEDI was calculated according to the proposal using only correct model test data, hull form, light ship weights and auxiliary machinery data. The EEDI results then in a permissible maximum engine power which can be installed into the ship. On design draft including sea and engine margin, this results in the permissible ship speed. Application: Most efficient RoRo in TUHH DB Consequence: Speed loss of 3.5 knots or design optimization! Optimization Potential The EEDI results in a permissible maximum engine power which can be installed into the ship. If the ship shall operate at a given speed, this permissible power can not be exceeded. This results in a permissible resistance of the ship at that speed. As the frictional resistance can hardly be influenced by the ship design, this results in a permissible wave resistance. Best performing ship in our DB (Ship Speed) Consequences Many ships require negative wave resistances to fulfill the EEDI! (The ship needs to gain energy from the waves) Is big really beautiful? Original Design Big New design Length m m Beam m m Draft 6.40 m 9.60 m DWT 9200 t t Speed kn kn MCR kw kw EEDI att EEDI req Excess Power kw kw Speed attained 19.1 kn The scatter is reduced from 19.6 to 7.7. Speed loss increases from 3.4 kn to 4.8 kn. ḷorigina. Big Other means of Transport Example: Airbus A 380 (freight version) Light Aircraft Weight : 286 t Max. Take Off Weight : 590 t (including 235t of fuel) Speed : 491 kn Consumption : 21.7 t/h Calculated EEDI for A 380: 342 Permissible EEDI for A 380: 333??? Obviously, there is something fundamentally wrong with the EEDI. Attained EEDI Some Basic Mathematics Required EEDI As If x equals 1 (RoRo: 0.78) this results in: (Violates basic principles of ship hydrodynamics!) Final Conclusions The EEDI trial applications show the following results: Both EEDI and baseline in combination violate basic physical principles. Technical possibilities of optimizing the ship design are extremely limited (except significant speed reduction). The worst problems can be healed if the relevant variables are used for a revised baseline definition. The baseline concept can be improved, further work is necessary! The EEDI will then be a powerful instrument to reduce CO 2 Emissions!
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x