Dr. George Gougoulidis – Hellenic Navy

Wind energy Solar energy

Combinations

Photovoltaic Sails Kites Flettner rotors Wind turbines cells

Traditional

Rigid‐foils

Maltese Falcon – 88m superyacht  Hybrid sailing 8000 DWT multi‐purpose cargo vessel for Fairtransport BV  4 Dynarig masts ~ 4000 m²  Diesel electric propulsion system of 3.000 kW  LOA = 138 m  Draft max = 6.50 m  Airdraft = 62.50 m (Panamax)  Deadweight @ 6.50 m = 8210 tn  Displacement = 11850 tn  Design speed on engines = 12 kt  Max speed on sails = 18 kt  Simple sail structure with good lift performance between 90° and 170°  Collapsible & mastless OCEANFOIL‐WINGSAIL WINDSHIP  2 x 35 m high masts  3 aerodynamic wings per mast  Automatic rotation of masts  System tested by LR  It can provide 50% of thrust under favorable conditions  University of Tokyo & major shipping companies (2009)  “Sail main, Engine assist”  Sail height x width = 50m x 20m  ~ 30 % average energy savings per year on a 84,000 tn bulk carrier with 4 sails In Jan 2014 on‐land test for a retractable rigid sail (1/2.5 size) SWIFT WINGS SHIN AITOKU MARU FORMER USUKI PIONEER

SkySails GmbH

 5 ships  Theseus and Michael A  L = 90 m  3,700 dwt  Main engine = 1,500 kW  Sail area = 160 m²

SkySails GmbH  Based on the Magnus Effect  Velocity field change → pressure field change → force  Developed by Anton Flettner in 1924  Official presentation of Rotor Ship in Hamburg in 1925  Voyage to New York in 1926  2 rotors 15m high, 3m diameter  The rotors need another energy source  Usually driven by electric motors  The power needed for the rotors is considerably smaller to the thrust produced  8‐10 times more thrust than sails of equal surface area  The ship cannot sail downwind or upwind  Side winds will produce thrust  The rotors can also be used to slow the vessel down, or to assist in maneuvering  Availability of space and general arrangements 4 Flettner rotors 27 m tall, 4m in diameter

 Rotors interfere with crane operations  Solution: telescopic or foldable Flettner rotors  WindAgain designed a range of Collapsible Flettner Rotors (CFR) . Wing flap to enhance performance . Folded when not in use  Fuel savings ↓ as the ship size ↑  For small ships savings up to 60% have been achieved  Savings of up to 19% on VLCC are being modelled  Enercon reported in 2013 that the E‐Ship 1 had achieved 25% savings after 170 000 sea miles  They allow sailing against the wind  Directly coupled to a water propeller, or used to produce electricity

 An international association has been created last October to facilitate and promote wind propulsion for commercial shipping worldwide  Earth’s average solar irradiance on the surface is approximately 342 W/m²  On average, 30% of this radiation will be reflected back to space due mainly to clouds  The amount of energy captured depends on efficiency and positioning  Current solar cells’ efficiency ~13% Current Current best Future Approximate energy conversion efficiency (%) 13 30 60 Nominal power (W/m2)44103205 Power adjusted for reflection (W/m2)3172144  Tanker: L=270 m & B=50 m  1 main engine @ 18,000 kW, and auxiliary power 1,000 kW  Tanker’s deck area completely covered by solar cells

Current Current best Future Approximate energy conversion efficiency (%) 13 30 60 Nominal power (kW) 609 1406 2811 Power adjusted for reflection (kW) 426 984 1968  Car carriers Auriga Leader & Emerald Ace  Part of the vessel’s electricity is generated via solar panels  Hybrid electric power supply system  768‐panel 160kW solar generation system  Lithium‐ion storage battery system of 2.2MWh  Used while in port  Charging time: 3 days underway Length: 199.9 m, Beam: 32.26 m  Craig Loomes design  Launched 3/2010 in Kiel  First solar‐powered trip around the world in 584 days (May 4, 2012)  L = 31 m  B= 15 m

 Higher capital expenditure  Performance depends on weather conditions  Good overall performance  Bulky and heavy equipment  Limited to certain types of ships  Small number of applications – maturity  May need new classification rules  Insurance Companies adopting an Energy efficiency energy efficiency technology adopted technology in the last 5 years

30% 14% hull coatings other technology adopting 70% not adopting

86%  The UCL study shows that the maritime industry prefers easy‐to‐apply and well‐ proven technological solutions  Not foreseeable in the near future whether renewable energy sources will gain extensive popularity among shipbuilders and owners  They will take a small share of the energy efficiency market Eurostat 19‐3‐2015