Dehlsen Associates LLC Concept Design Review Aquantis C-Plane Ocean Energy Conversion

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Dehlsen Associates LLC conducted a Concept Design Review for the Aquantis C-Plane Ocean Energy Conversion project presented by the Naval Surface Warfare Center, featuring detailed analysis of various concepts including stability, wing design, and different configurations. The review included visual representations and data on rotor and nacelle computational fluid dynamics, mean forces, moments, and flow conditions. The study took place on May 3-4, 2011, providing valuable insights into innovative ocean energy conversion technologies.

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Dehlsen Associates LLC Concept Design Review Aquantis C-Plane Ocean Energy Conversion Presented by Naval Surface Warfare Center Carderock Division Rich Banko 3 - 4 May 2011 05 Aug 2009

Dehlsen Associates LLC Notional Concept Analyzed for Vertical Plane Stability Nacelle Standard Wing 147 ft Span 23 ft Cord 12o Nose Up Horizontal Fairing 30 in Diameter Nose 10 ft Cord 147 ft Span Straight Taper to Trailing Edge Concept Design Review of Aquantis C-Plane 3-4 May 2011 2

Dehlsen Associates LLC Alternate Concept with Longer Nose Cone Nacelle FWD Nose Extended to 30 ft Wing 147 ft Span 23 ft Cord 12o Nose Up Horizontal Fairing 30 in Diameter Nose 10 ft Cord 147 ft Span Straight Taper to Trailing Edge Concept Design Review of Aquantis C-Plane 3-4 May 2011 3

Dehlsen Associates LLC ARL Rotor & Nacelle CFD Data Flow Conditions Mean Forces Fy Mean Moments Flow Speed Fx Fz Mx My Mz AoA (deg) 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 Rotor (rpm) 1.27 1.27 1.27 1.27 1.27 1.27 2.53 2.53 2.53 2.53 2.53 2.53 3.80 3.80 3.80 3.80 3.80 3.80 2.80 2.80 2.80 2.80 2.80 2.80 2.05 2.05 2.05 2.05 2.05 2.05 1.85 1.85 1.85 1.85 1.85 1.85 (m/s) 0.50 0.50 0.50 0.50 0.50 0.50 1.00 1.00 1.00 1.00 1.00 1.00 1.50 1.50 1.50 1.50 1.50 1.50 1.70 1.70 1.70 1.70 1.70 1.70 2.00 2.00 2.00 2.00 2.00 2.00 2.50 2.50 2.50 2.50 2.50 2.50 (f/s) 1.64 1.64 1.64 1.64 1.64 1.64 3.28 3.28 3.28 3.28 3.28 3.28 4.92 4.92 4.92 4.92 4.92 4.92 5.58 5.58 5.58 5.58 5.58 5.58 6.56 6.56 6.56 6.56 6.56 6.56 8.20 8.20 8.20 8.20 8.20 8.20 (kN) 130 126 128 126 121 114 504 493 497 490 469 442 1,111 1,115 1,098 1,078 1,037 979 1,289 1,277 1,266 1,243 1,196 1,132 1,384 1,377 1,350 1,303 1,224 1,147 1,382 1,404 1,365 1,277 1,262 1,265 (lb) 29,182 28,333 28,688 28,319 27,103 25,563 113,362 110,921 111,780 110,089 105,503 99,388 249,695 250,752 246,818 242,367 233,104 220,198 289,801 287,171 284,518 279,460 268,917 254,506 311,113 309,584 303,515 292,971 275,234 257,878 310,619 315,564 306,842 287,149 283,597 284,428 (kN) 0 -1 -1 0 0 0 -2 -1 0 1 1 2 -4 -2 0 2 3 5 -6 7 10 17 24 29 -3 23 46 69 94 107 0 33 56 82 127 212 (lb) 4 -177 -131 -45 -60 -74 -486 -303 -67 147 225 337 -998 -502 104 525 722 1,199 -1,434 1,515 2,280 3,915 5,360 6,567 -656 5,096 10,323 15,528 21,204 24,066 50 7,319 12,675 18,419 28,638 47,626 (kN) 0 2 3 4 6 7 0 6 12 18 23 28 0 15 29 39 51 62 2 25 40 58 75 90 5 25 44 63 83 102 4 5 14 45 51 46 (lb) 33 372 720 970 1,340 1,606 76 1,439 2,782 3,979 5,103 6,205 68 3,294 6,428 8,827 11,425 13,880 532 5,528 9,055 13,147 16,753 20,213 1,204 5,558 9,988 14,215 18,671 22,946 963 1,072 3,149 10,035 11,425 10,388 (kN-m) 260 247 254 250 233 212 1,069 1,034 1,054 1,034 971 890 2,397 2,417 2,373 2,315 2,189 2,019 4,526 4,493 4,447 4,353 4,141 3,865 7,816 7,758 7,547 7,164 6,483 5,873 4,593 4,748 5,009 5,124 5,581 6,516 (M in.-lb) 2.30 2.19 2.25 2.21 2.06 1.88 9.46 9.15 9.33 9.15 8.59 7.88 21.21 21.39 21.01 20.48 19.38 17.87 40.05 39.76 39.36 38.53 36.65 34.21 69.18 68.66 66.79 63.40 57.38 51.98 40.65 42.02 44.34 45.35 49.40 57.67 (kN-m) -2 -20 -37 -55 -70 -83 0 -92 -163 -234 -304 -359 -6 -197 -364 -534 -692 -820 -27 -171 -314 -434 -552 -640 -88 -217 -344 -495 -793 -915 -132 -100 -190 -506 -707 -1,388 (M in.-lb) -0.02 -0.18 -0.33 -0.49 -0.62 -0.74 0.00 -0.81 -1.44 -2.07 -2.69 -3.18 -0.05 -1.74 -3.22 -4.73 -6.12 -7.26 -0.24 -1.52 -2.78 -3.84 -4.89 -5.67 -0.78 -1.92 -3.04 -4.38 -7.02 -8.09 -1.17 -0.88 -1.68 -4.48 -6.26 -12.28 (kN-m) -7 -7 -9 -12 -14 -17 -24 -32 -36 -43 -50 -59 -54 -67 -81 -94 -112 -135 -29 38 129 204 265 304 -21 449 882 1,259 1,429 1,503 -27 700 1,178 1,243 1,675 2,465 (M in.-lb) -0.06 -0.06 -0.08 -0.11 -0.13 -0.15 -0.21 -0.28 -0.32 -0.38 -0.44 -0.52 -0.48 -0.59 -0.72 -0.83 -0.99 -1.19 -0.25 0.34 1.14 1.81 2.35 2.69 -0.19 3.97 7.80 11.15 12.64 13.31 -0.24 6.19 10.42 11.00 14.82 21.82 Concept Design Review of Aquantis C-Plane 3-4 May 2011 4

Dehlsen Associates LLC ARL Data Plots Single (Rotor + Nacelle) Drag Force 350,000 300,000 250,000 Drag (Fx) Force, lb 0 Pitch 200,000 +5 AoA +10 150,000 +15 +20 100,000 +25 50,000 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Current Velocity, m/s Concept Design Review of Aquantis C-Plane 3-4 May 2011 5

Dehlsen Associates LLC ARL Data Plots Rotor pitch moment vs. AoA (angle of attack) is negative, indicating stable configuration since the rotor is always tending to decrease its AoA and return to 0 pitch angle when perturbed. This characteristic is due to the rotor rake angle of 10 . Rotor yawing moment due to pitch AoA goes negative to positive but will be nulled by the opposing rotor moment that will be opposite due to counter-rotation. Single (Rotor + Nacelle) Yawing Moment Single (Rotor + Nacelle) Pitching Moment 25 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 20 Pitching Moment (Mz), 10E6 in-lb Yawing Moment (Mz), 10E6 in-lb 15 -5 0 Pitch 0 Pitch +5 AoA +5 AoA +10 +10 10 +15 +15 +20 +20 5 -10 +25 +25 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 -5 -15 Current Velocity, m/s Current Velocity, m/s Concept Design Review of Aquantis C-Plane 3-4 May 2011 6

Dehlsen Associates LLC Summation of ARL Data for 2 Rotor System Using single rotor data to obtain 2-rotor forces and moments Port rotor turns counterclockwise (ccw) and the starboard rotor turns clockwise (cw) The combined forces in the 3 directions for 2-rotors are: FX tot = FX port rotor + FX stbd rotor = 2 x FX single rotor FY tot = FY port rotor FY stbd rotor = 0 FZ tot = FZ port rotor + FZ stbd rotor = 2 x FZ single rotor The combined moments in the 3 directions for 2-rotors are: MX tot = MX port rotor - MX stbd rotor = 0 MY tot = MY port rotor + MY stbd rotor = 2 x MY single rotor MZ tot = MZ port rotor - MZ stbd rotor = 0 Concept Design Review of Aquantis C-Plane 3-4 May 2011 7

Dehlsen Associates LLC Wing Data Wing characteristics pertain to NACA 0018, 0020, 2418, 2421 type shapes Aerodynamic center located at 25% chord, center of mass located at about 42% chord Wing Lift vs. AoA 147ft span x 23ft chord Wing Drag vs. AoA 147ft span x 23ft chord 180,000 10,000 160,000 8,000 140,000 0.5 m/s 0.5 m/s 120,000 Wing Drag (lb) Wing Lift (lb) 1.0 1.0 6,000 100,000 1.5 1.5 80,000 4,000 1.6 1.6 60,000 1.7 1.7 40,000 2,000 2.0 2.0 20,000 0 2.5 0 2.5 0 2 4 6 8 10 12 14 0 2 4 6 8 10 12 14 Wing Angle of Attack (deg) Wing Angle of Attack (deg) Concept Design Review of Aquantis C-Plane 3-4 May 2011 8

Dehlsen Associates LLC Static Stability Static stability refers to the ability to react to static (weight & buoyancy) and steady hydrodynamic forces (rotor &wing) induced on the platform to seek a neutral and balanced attitude not resulting in increasing forces and moments Three planes of static stability to consider: Vertical or pitch plane (forces in the z-direction, moments about the y- axis) Lateral or yaw plane (forces in the x-direction, moments about the z- axis) Horizontal or roll plane (forces in the y-direction, moments about the x- axis) To date, vertical plane stability has only been investigated on a preliminary basis Concept Design Review of Aquantis C-Plane 3-4 May 2011 9

Dehlsen Associates LLC Vertical Plane Free Body Diagram Navy Coordinate System X+ BN+R Z+ Y+ LW BW BT DN+R DW My WW TML WT WN+R ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) = Subscripts N+R=Nacelle+Rotor Characteristics W=Wing Characteristics BT= FWD Buoyancy Trim Pod Characteristics TW= AFT Trim Weight Characteristics + + + + + = 2 2 2 0 B X W X M W X B X L X L X B X W X + + M N R CB N R CG Y W CG W CB W CB W AC T CB TW CG + + A N R N R W W w W BT TW Concept Design Review of Aquantis C-Plane 3-4 May 2011 10

Dehlsen Associates LLC Vertical Plane (Pitch) Static Stability Developed a spreadsheet for summing the moments about the tow point location (positioned on the nacelle vertical centerline to avoid large induced moments by the rotor drag force) An effective tow point located at the nose of the nacelles is unfeasible due to the large moments produced by the nacelle and wing buoyancy , and the increasing MY moment in the 1.5 to 2.5 m/s flow velocity range Determined the location of the tow point for which all static and hydrodynamic moments balance for various platform net buoyancy (total displacement of sea water air weight) The larger the net buoyancy of the platform, the further aft the tow point must be located (may cause a problem with yaw stability) Investigated using a forward located buoyancy pod (10,000 lb net buoyancy) and aft located counter-weight pod (10,000 lb heavy in sea water). Fwd & Aft Pods located 20ft or 30 ft ahead or aft of the nose or stern of the nacelle. Concept Design Review of Aquantis C-Plane 3-4 May 2011 11

Dehlsen Associates LLC Stability Spreadsheet Results for 1.5 m/s Flow Case # 1 Case # 2 Case # 3 1.50 m/s 1.50 m/s 1.50 m/s Current Velocity Mooring Loc'n Current Velocity Mooring Loc'n Current Velocity Mooring Loc'n Fwd tip of nacelle 0 0 0 Fwd tip of nacelle 0 0 0 Aft of fwd tip -360.1 x y z in. in. in. x y z in. in. in. x y z in. in. in. 0 0 Nacelle + Rotor Nacelle + Rotor Nacelle + Rotor OD 190.0 180.0 924.2 446,635 -472.4 -649,683 -472.4 -249,695 -998 -68 -21.21 -0.055 0.478 in. in. in. lb in. lb in. lb lb lb E6-in.-lb E6-in.-lb E6-in.-lb OD 135.0 125.0 924.2 375,000 -472.4 -385,000 -472.4 -249,695 -998 -68 -21.21 -0.055 0.478 in. in. in. lb in. lb in. lb lb lb E6-in.-lb E6-in.-lb E6-in.-lb OD 190.0 180.0 924.2 446,635 -472.4 -649,683 -472.4 -249,695 -998 -68 -21.21 -0.055 0.478 in. in. in. lb in. lb in. lb lb lb E6-in.-lb E6-in.-lb E6-in.-lb PV dia Length Weight air PV dia Length Weight air PV dia Length Weight air Xcg Xcg Xcg Buoyancy Buoyancy Buoyancy Xcb Xcb Xcb Fx (drag) Fy (side) Fz (lift) Mx (torque) My (pitching) Mz (yawing) Fx (drag) Fy (side) Fz (lift) Mx (torque) My (pitching) Mz (yawing) Fx (drag) Fy (side) Fz (lift) Mx (torque) My (pitching) Mz (yawing) Wing (2418 shape) Wing (2418 shape) Wing (2418 shape) Span Chord 147.0 23.0 87,142 -96.6 -153,856 25.0% -115.9 12.0 -58,646 -3,325 -69.0 ft ft lb in. lb % in. deg lb lb in. Span Chord 147.0 23.0 87,142 -96.6 -92,314 15.0% -115.9 12.0 -58,646 -3,325 -69.0 ft ft lb in. lb % in. deg lb lb in. Span Chord 147.0 23.0 87,142 -96.6 -153,856 25.0% -115.9 12.0 -58,646 -3,325 -69.0 ft ft lb in. lb % in. deg lb lb in. Weight air Weight air Weight air Xcg Xcg Xcg Buoyancy Vol displaced Buoyancy Vol displaced Buoyancy Vol displaced Xcb AoA Xcb AoA Xcb AoA Hydro Lift Hydro Drag Hydro Lift Hydro Drag Hydro Lift Hydro Drag Xac Xac Xac Fwd Buoyancy Pod Fwd Buoyancy Pod Fwd Buoyancy Pod Net Buoy. (B-W) lb in. lb Net Buoy. (B-W) -10,000 240 lb in. lb Net Buoy. (W-B) -10,000 240 lb in. lb Xcb Drag 1 Xcb Drag Xcb Drag Aft Trim Weight Aft Trim Weight Aft Trim Weight Wt in SW lb in. lb Wt in SW 11,600 -1164.2 lb in. lb Wt in SW 10,000 -1164.2 lb in. lb Xcg Drag -1 Xcg Drag Xcg Drag Overall Platform Overall Platform Overall Platform Lift Drag -531,592 -502,715 731,651 1.06 46.6 1,490 lb lb lb Lift Drag -82,354 -502,715 509,416 0.16 9.3 6,695 lb lb lb Lift Drag -531,592 -502,715 731,651 1.06 46.6 1,490 lb lb lb Tension L/D ratio Line Angle Line Length Tension L/D ratio Line Angle Line Length Tension L/D ratio Line Angle Line Length deg wrt horiz ft deg wrt horiz ft deg wrt horiz ft Sum of Moments about Y-axis at 0,0,0 Sum s/b near 0 Sum of Moments about Y-axis at 0,0,0 Sum of Moments about Y-axis at -360.1,0,0 -205,412,523 in.-lb 17,951 in.-lb 7,092 in.-lb Concept Design Review of Aquantis C-Plane 3-4 May 2011 12

Dehlsen Associates LLC Summary of Vertical Plane Stability Analysis Flow (m/s) Bnet (lb) Ltot (lb) D Tension (lb) Line Angle (deg) Xtp Locn (in. aft) Fwd Pod (lb) Aft Wt (lb) Line Length (ft) Case # L/D Notes (lb) 13 15 17 18 18.2 18.1 16 14 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -479,393 -479,393 -367,154 -367,154 -254,840 -254,840 -93,297 -21,255 -58,734 -58,734 -58,734 -58,734 -58,734 -58,734 -58,734 -58,734 482,978 482,978 371,822 371,822 261,521 261,521 110,246 62,462 8.16 8.16 6.25 6.25 4.34 4.34 1.59 0.36 83.0 83.0 80.9 80.9 77.0 77.0 57.8 19.9 0.0 -391.6 -255.8 -211.0 -289.5 -224.8 -207.8 0.0 0 0 1,090 1,090 1,096 1,096 1,111 1,111 1,279 3,181 1, 4, 7 2, 4, 7 6, 8 3, 6, 8 10,11 3, 10 11 4, 9 2, 5, 9 -10,000 0 -10,000 0 -10,000 0 0 10,000 0 10,000 0 10,000 0 10,500 7 9 11 12 12.2 12.1 10 8 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -499,028 -499,028 -386,788 -386,788 -274,474 -274,474 -112,932 -39,789 -228,202 -228,202 -228,202 -228,202 -228,202 -228,202 -228,202 -228,202 548,730 548,730 449,089 449,089 356,949 356,949 254,617 231,645 2.19 2.19 1.69 1.69 1.20 1.20 0.49 0.17 65.4 65.4 59.5 59.5 50.3 50.3 26.3 9.9 0.0 -378.9 -246.2 -203.7 -273.5 -213.6 -183.3 0.0 0 0 1,190 1,190 1,257 1,257 1,408 1,408 2,440 6,301 1, 4, 7 2, 4, 7 6, 8 3, 6, 8 10,11 3, 10 11 4, 9 2, 5, 9 -10,000 0 -10,000 0 -10,000 0 0 10,000 0 10,000 0 10,000 0 11,600 1 3 5 6 1.50 1.50 1.50 1.50 1.50 1.50 1.50 1.50 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -531,592 -531,592 -419,352 -419,352 -307,038 -307,038 -145,496 -82,354 -502,715 -502,715 -502,715 -502,715 -502,715 -502,715 -502,715 -502,715 731,651 731,651 654,660 654,660 589,063 589,063 523,347 509,416 1.06 1.06 0.83 0.83 0.61 0.61 0.29 0.16 46.6 46.6 39.8 39.8 31.4 31.4 16.1 9.3 0.0 -360.1 -232.7 -193.5 -252.2 -198.6 -158.4 0.0 0 0 1,490 1,490 1,690 1,690 2,077 2,077 3,893 6,695 1, 4, 7 2, 4, 7 6, 8 3, 6, 8 10,11 3, 10 11 4, 9 2, 5, 9 -10,000 0 -10,000 0 -10,000 0 -10,000 10,000 0 10,000 0 10,000 0 11,600 6.2 6.1 4 2 19 21 23 24 24.2 24.1 22 20 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -549,203 -549,203 -436,963 -436,963 -324,650 -324,650 -163,107 -101,565 -583,873 -583,873 -583,873 -583,873 -583,873 -583,873 -583,873 -583,873 801,581 801,581 729,277 729,277 668,061 668,061 606,227 592,641 0.94 0.94 0.75 0.75 0.56 0.56 0.28 0.17 43.2 43.2 36.8 36.8 29.1 29.1 15.6 9.9 0.0 -351.9 -227.2 -189.5 -243.8 -193.0 -151.5 0.0 0 0 1,580 1,580 1,806 1,806 2,227 2,227 4,023 6,316 1, 4, 7 2, 4, 7 6, 8 3, 6, 8 10,11 3, 10 11 4, 9 2, 5, 9 -10,000 0 -10,000 0 -10,000 0 -12,400 10,000 0 10,000 0 10,000 0 12,400 Concept Design Review of Aquantis C-Plane 3-4 May 2011 13

Dehlsen Associates LLC Summary of Vertical Plane Stability Analysis Flow (m/s) Bnet (lb) Ltot (lb) D Tension (lb) Line Angle (deg) Xtp Locn (in. aft) Fwd Pod (lb) Aft Wt (lb) Line Length (ft) Case # L/D Notes (lb) 25 27 29 30 30.2 30.1 28 26 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -579,479 -579,479 -467,239 -467,239 -354,925 -354,925 -193,383 -131,840 -628,137 -628,137 -628,137 -628,137 -628,137 -628,137 -628,137 -628,137 854,606 854,606 782,859 782,859 721,476 721,476 657,231 641,824 0.92 0.92 0.74 0.74 0.57 0.57 0.31 0.21 42.7 42.7 36.6 36.6 29.5 29.5 17.1 11.9 0.0 -339.6 -219.7 -184.4 -232.6 -186.0 -144.6 0.0 0 0 1,596 1,596 1,814 1,814 2,200 2,200 3,679 5,269 1, 4, 7 2, 4, 7 6, 8 3, 6, 8 10,11 3, 10 11 4, 9 2, 5, 9 -10,000 0 -10,000 0 -10,000 0 -14,600 10,000 0 10,000 0 10,000 0 14,600 31 33 35 36 36.2 36.1 34 32 2.50 2.50 2.50 2.50 2.50 2.50 2.50 2.50 -472,811 -472,811 -360,571 -360,571 -248,257 -248,257 -86,715 -25,172 -637,643 -637,643 -525,403 -525,403 -413,089 -413,089 -251,547 -190,004 -630,473 -630,473 -630,473 -630,473 -630,473 -630,473 -630,473 -630,473 896,707 896,707 820,697 820,697 753,750 753,750 678,802 658,481 1.01 1.01 0.83 0.83 0.66 0.66 0.40 0.30 45.3 45.3 39.8 39.8 33.2 33.2 21.8 16.8 0.0 -315.8 -204.3 -172.9 -211.2 -171.2 -130.0 0.0 0 0 1,522 1,522 1,691 1,691 1,975 1,975 2,921 3,751 1, 4, 8 2, 4, 8 6, 9 3, 6, 9 10,12 3, 10 12 4, 10 2, 5, 10 -10,000 0 -10,000 0 -10,000 0 -18,050 10,000 0 10,000 0 10,000 0 18,050 Notes 1. Does not meet static stability 2. Fwd & Aft Trim Pods located 240 in. from most wd/aft stations of nacelle 3. Fwd & Aft Trim Pods located 360 in. frommost fwd/aft stations of nacelle 4. Wing foam filled to 25% of available displacement volume 5. Wing foam filled to 15% of available displacement volume 6. Wing foam filled to 50% of available displacement volume 7. Pressure Vessel 180 in. dia 8. Pressure Vessel 150 in. dia 9. Pressure Vessel 125 in. dia 10. Pressure Vessel 140 in. dia 11. Wing foam filled to 35% of available displacement volume Concept Design Review of Aquantis C-Plane 3-4 May 2011 14

Dehlsen Associates LLC Mooring Line Length and Tension Results For platform net buoyancy in the range of 250 klb (1,100 kN) to 473 klb (2,100 kN) the mooring line length required (2,200ft or 670m) is quite flat for flow in the 1.5 to 2.5 m/s range Required Mooring Line Length for 330 m Separation C-Plane to Sea Floor Mooring Line Tension for 330 m Separation from C-Plane to Sea Floor 8,000 1,000 7,000 900 800 Tension at C-Plane (klb, Lift + Drag) 6,000 Mooring Line Length (ft) 700 473 klb Net B 5,000 600 361 klb 473 klb Net B 248 klb 4,000 361 klb 500 87 klb 248 klb 400 3,000 25 klb 87 klb 300 Water Depth 25 klb 2,000 Nom Oper 200 1,000 100 0 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 Flow Velocity (m/s) 1.5 2.0 2.5 3.0 Flow Velocity (m/s)) Concept Design Review of Aquantis C-Plane 3-4 May 2011 15

Dehlsen Associates LLC Required Platform Lift The required total lift force (net buoyancy + wing lift) required for stability varies with flow velocity to counter the speed increasing pitching moment of the rotor Net Buoyancy to Lift Ratio vs Flow Velocity Required Total Lift for Various Net Buoyancy Values 1.0 700 0.9 600 0.8 Total Lift (klb, Buoyancy + Wing Hydro) Net Buoyancy-to-Total Lift Ratio 500 0.7 0.6 473 klb Net B 473 klb Net B 400 361 klb 0.5 361 klb 248 klb 248 klb 300 0.4 87 klb 87 klb 0.3 25 klb 25 klb 200 0.2 100 0.1 0 0.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Flow Velocity (m/s)) Flow Velocity (m/s) Concept Design Review of Aquantis C-Plane 3-4 May 2011 16

Dehlsen Associates LLC Platform L/D Ratio and Mooring Line Angle Platform Lift-to-Drag (L/D) ratio and mooring line angle wrt horizontal resulting from solving required stability moments Mooring line angles in the range of 30 to 60 (L/D ratio 0.6 to 1.7, respectively) would be most desirable to reduce mooring line lengths L/D Ratio vs Flow Velocity Mooring Line Angle from C-Plane to Sea Floor 3.0 90 80 2.5 Mooring Line Angle (deg wrt Horiz) 70 2.0 60 Lift-to-Drag Ratio 473 klb Net B 473 klb Net B 50 361 klb 1.5 361 klb 40 248 klb 248 klb 87 klb 87 klb 1.0 30 25 klb 25 klb 20 0.5 10 0.0 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Flow Velocity (m/s) Flow Velocity (m/s) Concept Design Review of Aquantis C-Plane 3-4 May 2011 17

Dehlsen Associates LLC Required Tow Point Location for Stability Nacelle length: 925 in. (23.5m) Trailing edge of wing: 276 in. (7.0m) aft of standard nacelle nose Tow point variation: 25 in. (0.6m) from nominal operation location at 1.6 m/s flow Tow Point Location for Static Stability vs. Net Buoyancy 450 400 350 Req'd Tow Point Location (in. aft of Nacelle Nose) 473 klb w/ Pods 300 361 klb no Pods 250 361 klb w/ Pods 200 248 klb no Pods 248 klb w/ Pods 150 87 klb no Pods 100 25 klb w/ Pods 50 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Flow Velocity (m/s) Concept Design Review of Aquantis C-Plane 3-4 May 2011 18

Dehlsen Associates LLC Concept Design Review of Aquantis C-Plane 3-4 May 2011 19

Dehlsen Associates LLC Concept Design Review of Aquantis C-Plane 3-4 May 2011 20

Dehlsen Associates LLC Estimated Weights & CG Locations for Major Components ARL Dec 10 Nacelle/Rotor configuration Aquantis C-Plane Mass Properties Date: 20 April 2011 Issue: 2 Based on Aquantis lay-out provided by ARL in Dec 2010 Qty Reqd per Nacelle Thick or Height (in.) Material Volume (in^3) Density Length Width / Dia. Surf. Area Weight (lb, + heavy) Component Center of Gravity Weight Moments for CG Item Part Description Material (S.G.) (lb/in.^3) (in.) (in.) (in.^2) Air (calc) Margin Air Total in SW X (in.) Y (in.) Z (in.) W*Xcg (in-lb) W*Ycg (in-lb) W*Zcg (in-lb) 1 Rotor Assembly 168"x40" rt 64"x7.7" tip 168"x40" rt 64"x7.7" tip 168"x40" rt 64"x7.7" tip 20"x32" rt 8"x6.5" tip 15"x24" rt 8"x9" tip Rotor blade #1 outer skin GFRP laminate 1 1.89 0.068 1.20 703.2 164,654 197,585 13,436 10.0% 14,779 6,720 698.6 -347.6 -10.1 10,325,434 -5,137,297 -149,271 Rotor blade #2 outer skin GFRP laminate 1 1.89 0.068 1.20 703.2 164,654 197,585 13,436 10.0% 14,779 6,720 698.6 173.8 301.0 10,325,434 2,568,748 4,448,972 Rotor blade #3 outer skin GFRP laminate 1 1.89 0.068 1.20 703.2 164,654 197,585 13,436 10.0% 14,779 6,720 698.6 173.8 -301.0 10,325,434 2,568,748 -4,448,972 Main Spar G/CaFRP laminate 3 1.56 0.056 1.20 703.2 135,231 162,277 9,088 10.0% 9,996 3,377 698.6 0.0 0.0 6,983,799 0 0 Aft Spar G/CaFRP laminate 3 1.56 0.056 0.90 703.2 114,345 102,911 5,763 10.0% 6,339 2,142 698.6 0.0 0.0 4,428,884 0 0 foam (Divinylcell, 16 pcf) steel steel steel steel Foam Plugs (internal to blade) 3 0.26 0.009 703.2 2,634,735 24,396 10.0% 26,835 -80,630 698.6 0.0 0.0 18,748,187 0 0 Spar-to-Hub Fitting Hub Fitting, Main Hub Fitting, Fwd & Aft Miscellaneous 3 1 6 1 7.94 7.94 7.94 7.94 0.286 0.286 0.286 0.286 40 100.0 50.0 30.0 59.0 80.0 15.0 7,500 18,000 2,400 5,500 10.0% 10.0% 10.0% 10.0% 8,250 19,800 2,640 6,050 7,180 17,233 2,298 5,266 698.6 698.6 698.6 0.0 0.0 0.0 0.0 0.0 0.0 5,763,780 13,833,072 1,844,410 0 0 0 0 0 0 0 0 0 10 743,538 3,492,677 112,953 11,295 82,578,433 198 -149,271 Rotor Assembly Subtotals 124,249 -22,974 2 Nacelle Exterior Fairings Nac. Nose Nac. Centerbody Nac. Hub Cone Nac. Spinner Miscellaneous GFRP laminate GFRP laminate GFRP laminate GFRP laminate steel 1 1 1 1 1 1.89 1.89 1.89 1.89 7.94 0.068 0.068 0.068 0.068 0.286 1.20 0.75 1.20 0.75 236.2 357.0 196.9 134.2 232.8 232.8 199.8 166.8 345,584 261,127 123,573 140,636 414,701 195,845 148,288 105,477 3,497 28,200 13,317 10,084 7,172 1,000 10.0% 10.0% 10.0% 10.0% 10.0% 31,020 14,649 11,092 7,890 1,100 14,105 6,661 5,044 3,587 957 136.0 414.7 686.0 834.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4,217,591 6,075,174 7,608,773 6,586,140 0 0 0 0 0 0 0 0 0 0 0 924.2 870,920 867,808 59,773 5,977 24,487,678 0 0 Nacelle Exterior Fairings Subtotals 65,750 30,354 Concept Design Review of Aquantis C-Plane 3-4 May 2011 21

Dehlsen Associates LLC Estimated Weights & CG Locations for Major Components Aquantis C-Plane Mass Properties Date: 20 April 2011 Issue: 2 Based on Aquantis lay-out provided by ARL in Dec 2010 Qty Reqd per Nacelle Thick or Height (in.) Material Volume (in^3) Density Length Width / Dia. Surf. Area Weight (lb, + heavy) Component Center of Gravity Weight Moments for CG Item Part Description Material (S.G.) (lb/in.^3) (in.) (in.) (in.^2) Air (calc) Margin Air Total in SW X (in.) Y (in.) Z (in.) W*Xcg (in-lb) W*Ycg (in-lb) W*Zcg (in-lb) 3 Inside Nacelle Pressure Hull A6VM1000 Hydr. Var. motor #1 A6VM1000 Hydr. Var. motor #2 MB 4000 Hydr. Var. motor #1 Torque Arm (TMA 140) Generator - 1,250kw steel steel steel steel steel steel / minrl oil 300gal steel steel steel steel copper/nickel 1 1 1 2 1 25.6 25.6 48.0 24.3 24.3 48.0 18.3 18.3 48.0 11,416 11,416 110,592 11,748 166,400 946 946 23,700 3,360 14,000 5.0% 5.0% 5.0% 8.0% 5.0% 993 993 24,885 3,629 14,700 946 946 23,700 3,360 14,000 423.2 563.2 276.2 276.2 493.2 -56.0 -56.0 0.0 420,365 559,427 6,873,735 1,002,347 7,250,040 -55,625 -55,625 0 0 -823,200 0 0 0 0 0 0.0 0.0 7.94 0.286 40.0 104.0 40.0 -56.0 Oil reservoir tank 1 40.0 80.0 35.2 112,640 2,625 8.0% 2,835 2,625 354.7 60.8 1,005,603 172,368 0 Accumulator Charge pump & oil filters Hydr. Lines (160ft) Hydr. Fittings Heat Exchanger Contactor & circuit breaker (200A) Rotor shaft Rotor bearings Hub flange Bearing Bulkhead (2 plts/blkhd) Bearing Saddle Miscellaneous 1 1 1 1 1 1 1 2 1 2 2 1 30.0 20.0 80.0 35.0 30.0 15.0 72,000 10,500 2,000 425 2,500 500 375 600 12,126 13,157 2,650 13,521 7,205 7,500 8.0% 8.0% 10.0% 10.0% 10.0% 8.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 2,160 459 2,750 550 413 648 13,339 14,473 2,915 14,873 7,926 8,250 2,000 425 2,500 500 300 600 12,126 13,157 2,650 13,521 7,205 7,500 354.7 314.7 414.7 414.7 414.7 533.2 414.7 414.7 573.2 414.7 414.7 414.7 -48.0 60.8 -32.0 -32.0 98.0 64.0 0.0 0.0 0.0 0.0 0.0 0.0 766,174 144,452 1,140,453 228,091 171,068 345,514 5,531,797 6,001,905 1,670,878 6,167,823 3,286,800 3,421,358 -103,680 27,907 -88,000 -17,600 40,425 41,472 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 steel steel steel steel steel steel 7.94 7.94 7.94 7.94 7.94 7.94 0.286 0.286 0.286 0.286 0.286 0.286 1.5 48.0 2.5 1.0 1.5 295.0 35.2 20.0 180.0 36.0 32.0 48.0 48.0 180.0 48.0 42,400 46,003 9,266 47,275 25,192 26,224 0.0 0.0 0.0 0.0 0.0 0.0 47,275 16,795 64,070 703,072 108,136 8,654 45,987,826 -861,557 0 Inside Pressure Hull Subtotals 116,790 108,061 4 Nacelle Pressure Hull End Dome, Fwd (2:1 ellipse) Flange External T-Rib Stiffeners Hatch & Reinforcements End Dome, Aft (2:1 ellipse) Flange External T-Rib Stiffeners Shaft Seal & Reinforcements Cylinder Section (180" dia) Flange Ext. T-Rib Stiffeners (20"btwn) Miscellaneous steel steel steel steel steel steel steel steel steel steel steel steel 1 1 7.94 7.94 7.94 7.94 7.94 7.94 7.94 7.94 7.94 7.94 7.94 7.94 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.286 0.75 1.5 0.5 2.0 0.75 1.5 0.5 2.0 0.75 1.5 0.5 45.0 188.0 70.0 48.0 45.0 188.0 70.0 48.0 357.0 188.0 584.0 180.0 188.0 3.0 48.0 180.0 188.0 3.0 48.0 180.0 188.0 3.0 50,894 27,759 2,310 1,810 50,894 27,759 2,310 1,810 201,867 55,518 28,908 38,170 41,639 1,155 3,619 38,170 41,639 1,155 3,619 151,401 83,277 14,454 26,224 10,917 11,909 330 1,035 10,917 11,909 330 1,035 43,301 23,817 4,134 7,500 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 10.0% 12,008 13,100 363 1,139 12,008 13,100 363 1,139 47,631 26,199 4,547 8,250 -44,540 11,401 316 991 -44,540 11,451 316 991 -288,815 22,802 3,958 7,180 221.2 236.2 221.2 191.2 608.2 593.2 608.2 593.2 414.7 414.7 414.7 414.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2,656,497 3,094,370 80,383 217,718 7,303,504 7,770,638 220,997 675,402 19,752,895 10,865,008 1,885,781 3,421,358 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 12 1 1 1 12 1 1 2 18 1 451,839 444,522 127,133 12,713 57,944,551 0 0 Nacelle Pressure Hull Subtotals 139,847 -318,489 210,998,488 Xcg (in.) 472.4 -861,359 Ycg (in.) -1.9 -149,271 Zcg (in.) -0.3 407,996 38,640 Totals per Nacelle 446,635 -203,048 Concept Design Review of Aquantis C-Plane 3-4 May 2011 22

Dehlsen Associates LLC Estimated Weights & CG Locations for Major Components Based on ARL Dec 10 Nacelle/Rotor Configuration Rotor Assembly: Length: 703 in. (17.9m); Root chord: 168 in. (4.27m); tip chord: 64 in. (1.63m) Wt: 124,200 lb air; -23,000 lb in sea water (SW) buoyant Blades: Wt: 31,900 lb ea air; - 47,800 lb in sea water (SW) net buoyant Laminated carbon/glass fiber/vinyl ester resin spars & skins, foam filled interior to preclude water intrusion (imbalance) Tave = 1.20 in. (3.0cm) Hub Fittings: Wt: 28,500 lb air; 25,000 lb in SW Concept Design Review of Aquantis C-Plane 3-4 May 2011 23

Dehlsen Associates LLC Estimated Weights & CG Locations for Major Components Nacelle Exterior Fairings Length: 924 in. (23.47m); Outside Diameter: 236 in. (6.0m) Laminated glass fiber /vinyl ester resin Tave = 1.00 in. (2.5cm) Wt: 65,800 lb air: 30,400 lb in SW (heavy) Drive train, shafting, bearings & hydraulic/electrical equipment internal to the pressure hull Wt: 116,800 lb air; 116,800 lb in SW (in housing, no displacement) Pressure Hull (with external T-rib stiffeners) Diameter: 180 in. (4.57m) Length: 447 in. (11.35m) Wt: 139,850 lb air; -318,500 lb in SW (buoyant) Concept Design Review of Aquantis C-Plane 3-4 May 2011 24

Dehlsen Associates LLC Pressure Hull Diameter vs. Weight in Sea Water Negative weight in sea water means positively buoyant (floats) Housing length: 447 in. ( 11.35m) Nacelle/Rotor Estimated Weight in Water vs Pressure Housing Diameter (per Nacelle) Nacelle/Rotor Estimated Weight in Water vs Pressure Housing Diameter (per Nacelle) 200 50 0 0 3.0 3.5 4.0 4.5 5.0 Weight in Sea Water (kN) Weight in Sea Water (klb) 9.0 10.0 11.0 12.0 13.0 14.0 15.0 16.0 ( - is positive buoyancy) ( - is positive buoyancy) -200 -50 -400 -100 -600 -150 -800 -1,000 -200 Nacelle Pressure Housing Diameter (m) Pressure Housing Diameter Nacelle Pressure Housing Diameter (ft) Concept Design Review of Aquantis C-Plane 3-4 May 2011 25

Dehlsen Associates LLC Estimated Weights & CG Locations for Major Components Nacelle / Rotor Assembly Wt air: 446,600 lb (1,988 kN) Wt SW: - 194,300 lb (864 kN buoyant) Xcg: 472 in. (12.0m) aft of fwd end of nose Xcb: 472 in. (12.0m) aft of fwd end of nose (estimated same as CG) Zcg & Zcb have not been estimated at this time Concept Design Review of Aquantis C-Plane 3-4 May 2011 26