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VESSEL OPERATION ECONOMIES ...
Engine
maintenance and fuel consumption is based on hours of operation,
and then translated to distance of travel. We will talk more about
speed and time later. Any two identical engines will consume a
predictable amount of fuel at the rated rotational speed and horsepower
of each engine. If each of those engines is placed in a different
vessel (ship #1 and ship #2) of identical GWT (Gross Weight Tons) and
hull shapes, then each will consume the same amount of fuel for each
hour of operation.
However, if ship #2 traveled at twice the speed of the first ship
using the same engine, then ship #2 has twice the operational fuel and
maintenance efficiencies of ship #1. The only way this could be
possible is if ship #2 has a moving resistance in water that is half of
ship #1's moving resistance (lower drag). This can be observed by
comparing a barge and a frigate having the same GWT and horsepower. The
barge is analogous to moving a
"barn
door" through the water,
while the 8:1 aspect ratio and streamline bow, of the frigate, allows
for lower moving resistance and thus, higher speeds for the same amount
of engine running time. Accordingly, boat #2 may travel twice the
distance between engine overhaul requirements, having both a cost
savings of fuel and a down time (a period of no revenue) savings.
Therefore, the frigate completes twice the miles traveled for the same
amount of fuel and maintenance spent by the powered barge of like
tonnage. This is generally the difference of conventional ships
resulting from
drag and
bow wake, when compared
to a Hydro Lance ship or boat.
If the same comparison could be made of two, 175 GWT, 250
passenger ferry boats, having differences of hull design (boat #1 and
boat #2), then the operational costs of boat #2 would be half that of
boat #1. The feature of "twice-the-speed", when considering increased
revenue, may be of greater value than the operational savings. Boat #2
would be capable of completing twice as many route trips as boat #1 in
the same amount of time, thus twice the gross revenue at less operating
costs, as twice the miles were then traveled. If boat #2 were placed on
the same route of boat #1, then boat #1 would become non-competitive and
soon obsolete. Of course, this depends on market, occupancy and patron
needs.
Mono-hull:
Diesel engine fuel consumption is approximately .29 pounds per
hour, per horsepower, of operational time. A modern 250 passenger, 200
GWT mono-hull ferry will utilize approximately 5,920 horsepower to
travel at a speed of 24 knots up and through an approximate Beaufort sea
state 4 (higher Beaufort sea states demands that these planning or ‘V’
hulls must use slower speeds to avoid hull stress, discomfort and/or
wave 'slamming'. Considering that there is approximately seven pounds
to the U.S. gallon of diesel, then that ferry would consume
approximately 245 gallons per hour of fuel...and would have traveled 24
nautical miles in one hour. At the approximate Diesel cost of $2.80 per
gallon US (this cost varies greatly worldwide), the cost of fuel would
be $686 (US) per hour of operation at said speed in said calm waters.
The new high-tech world has ushered in
catamaran designs for ferry
operations. The objective is greater speed with greater stability (for
passenger comfort). Greater speeds means more operational trips can be
made, which equates to increased passenger revenue. That revenue
increase may offset losses due to increased fuel costs. Bazon, Incat,
Austral Ships and Wave Master are among the leaders of this catamaran
industry. They have delivered into service approximately 190+ new
state-of-the-art catamaran vessels during the past several years.
The Abraham Class Catamaran
This new twin-hull vessel is 411 feet long with a beam of
61.3 feet. The draft is 37 feet and totals a weight of 475 (DWT)
tons. Each will carry 135 cars on one deck and 109 on the second. Up
to 600 passengers will occupy the upper decks, three and four. The
water-jet drive is powered by 33,900 KW of total diesel horsepower for a
loaded speed of 39 knots in a maximum sea state of Beaufort Number 5.
The catamaran vessel must
slow down in greater
Beaufort Sea states
to avoid dangerous
'tunnel slamming'
and structural damage. Accordingly, this vessel will consume
approximately 9,831 pounds of fuel for each
hour of operation...or in the range of 1,404 gallons of
diesel fuel per hour. Translated to cost (exampled $2.80 gallon
– U.S.), that consumption is approximately $3,931 (US) per hour of
operation, during which time the boat will have traveled 39 nautical
miles. Noteworthy, is that in most elevated force sea-states, CATS must
slow way down to perhaps 8-10 Knots in order to avoid
tunnel slamming
and bow wave crashes, which
significantly compromises structural reliability and the actual cruising
speeds in many of the traveled markets, as in the real world are
elevated seas beyond these noted relatively calm waters.
However, assuming that the CAT can sustain speed
throughout an assigned route, compared that to the first exampled
mono-hull ship example at $686 per hour of fuel operation for a distance
of 24 nautical miles that higher speed and ship size would indeed,
offset the added fuel cost with more route trips (revenue) in the same
amount of time.
For
ongoing comparisons, these costs would have to be observed as
passenger miles (or cargo weight) per ton miles of ship displacement vs.
fuel consumption and maintenance.
The Mestral Class Catamaran
This catamaran is smaller, having a length of 312 feet and
a beam of 48 feet. The boat has a draft of 29.2 feet and weighs in at
175 DWT (Dead Weight Tons). Water-jets drive the vessel with 20,000
horsepower (TSFC gas turbine) for a loaded cruising speed of 32 knots
(speed must be reduced in sea-states above Beaufort Number 4, or
certainly Force 5, to avoid tunnel slamming and bow/wave crashes).
Modern TSFC Gas turbines consume approximately.34 (1/3+) pounds
per horsepower / per hour of JP-4 fuel at sea-level (JP-4 is more
expensive per gallon; example: $3.10/gallon U.S. and weighs 6.5 pounds
per gallon. Accordingly, the operational cost equates to approximately
$2,919 per hour, in which time the boat travels 32 nautical miles with
310 passengers. Newest heat recovery turbine technologies may improve
this economy slightly if the added space required would permit such use.
Noteworthy: The B60-MD Class
Catamaran
Similar and modified from the (above) Abraham class
catamaran vessel, the B60-MD, can carry more coaches and travel at a
higher speed and features a lesser draft with a displacement weight of
approximately 220 tons. The vessel will be powered by four new
Caterpillar engines (now in development), each having 42,000 horsepower,
or a total of 168,000 horsepower for a loaded top speed of 53
knots in a maximum sea state of a 5 Beaufort Scale (higher sea-states
will demand a significantly slower speed to avoid tunnel plugs and
slamming). The fuel cost to operate this 474 DWT vessel computes to
$27,242 per hour for a distance traveled of 53 nautical miles in one
hour in relatively calm waters, or approximately $124 per ton mile.
New State-of-the-art
engineering has now evolved to the newest class of marine design;
the Hydro Lance, which utilizes the
H.A.R.T.H.
(High Aspect Ratio Twin Hull) technology. Speed, ultra-stability
and sea keeping capabilities significantly exceed both state-of-the-art
mono-hulls and catamarans. Operational efficiencies are up to seven
times that of either the best of
mono-hull or
catamaran designs
in
and
through elevated sea-states, also having
ultra-stability.
Hydro Lance Nirvana Class
(Image Click Here)
The
geometry of
this twin hull, designed
for 170-230 DWT vessels, is significantly different from the catamaran.
Compared to the Mestral Class catamaran noted above, which has a draft
of 29.2 feet (depth from the waters surface to the bottom of the hull),
the Hydro Lance
Nirvana Class
has only three feet of draft. Where the bows of the catamaran
have a bow entry ratio of approximately 8:1, the bow entry ratio of the
Hydro Lance is significantly higher. The Catamaran has a deeper draft;
the Hydro Lance has a shallow draft with no or insignificant bow wake
generation, lower hull drag and greatly reduced hull and
structure stresses in high seas. The Hydro Lance includes a proprietary
low energy surface drag reduction system possible only with the HARTH
hull geometry. The catamaran, SWATH, SLICE, Hydrofoil and other ships
types all have significantly greater hull drag. The result is that a
HARTH ship
will have a total
reduction
in the resistance
to forward vessel hull movement (drag) by approximately 83%.
Accordingly, a similar sized Hydro Lance would require
only 5,000 total horsepower to travel at
the same exampled speeds of the Mestral Class catamaran. Therefore, the
cost of fuel could be compared at $810 per hour for that vessels speed
of 39 nautical miles in one hour, or approximately $4 per ton mile.
However, since speed is so very sensitive to trip time and increased
revenues, this vessel would be equipped for 60-90 knots of cruising
speed. Two 5,400 horsepower gas turbines ($1,686 per hour of
JP-4 fuel) would provide a 75 knot cruising speed through a Beaufort
sea-state 7 (greater Beaufort sea states would require a modest change
of course heading), or approximately $8.43 per ton mile. Unlike the
mono-hull or catamaran, the Beaufort 7 sea-state rating of the HL
Nirvana class, does
not slow down the Hydro Lance (See
Sea State Forces).
Travel route schedules can be kept routine, regardless of
weather, short of near hurricane forces, which the greater Hydro Lance
speeds can easily outrun or circumvent. These speed differences also
translate to the distances traveled between engine overhauls and
down-time. Underway, in the Sea State 6
or
7 condition, pitch is
eliminated, roll is
limited
to a maximum of +5 degrees (which can occur only in a worse-case
beam-sea when power is lost), and heave is eliminated. This
feature translates to the maximum of passenger comfort and safety, with
no roll, heave, pitch, hog, sag, sway, yaw or the effects of motion
sickness!
Comparing the Hydro Lance Nirvana class ship to the
mono-hull and the Mestral class catamaran vessels, the state-of-the-art
200 ton mono-hull ferry (310 passenger capacity) consumes $686 per hour
of fuel to travel 24 nautical miles in a sea state of Beaufort 4. The
175 ton Mestral class (250 passengers) catamaran consumes $3,931 per
hour of fuel to travel 32 nautical miles in a sea state of Beaufort 4
scale. The 200 ton Nirvana class Hydro Lance faster ferry (310
passenger capacity) consumes $1,686 per hour of fuel to travel 72-80
nautical miles through a Sea State of Beaufort 6-7. In this sea state,
the other exampled more conventional vessels would be forced to travel,
at reduced speeds, of
approximately 8-12 Knots, and in great
discomfort.
Each
Hydro Lance ferry
could complete approximately three trips for every one trip that
the mono-hull completes one trip, and two trips for every one trip that
the Mestral class catamaran completes. In
Sea States of Beaufort 5 or 6,
the disparity is even greater. Larger Hydro Lance Ferries
can pass
through at speed, even at
higher Force 8 Sea States.
Profit Differences:
Accordingly,
in calm waters, and all three vessels are at capacity, charging a $58
fare for a one-way,130 mile trip, the Nirvana class 310 passenger
Hydro Lance would generate a gross revenue of $71,920 in the same time
that the 310 passenger mono-hull would generate $17,980 and that
the 310 passenger catamaran would generate $35,960. In that
same130 mile trip distance, the Hydro Lance ship (4 trips) would spend
$11,668 for fuel, the mono-hull (1 trip) would spend $3,704 for fuel and
the catamaran (2 trips) would spend $11,676 for fuel.
Operations:
Most
ferry operations do not operate at peak capacity every day of the year,
if just for season demand variations. Accordingly, operators will
adjust their route schedules to either include less or more frequent
trips in order to hold an approximate 80% client passage on each trip.
Below is adjusting the ‘profit differences’ above to a
reduced 75% passage of 200 patrons instead
of the 310 peak capacity...
Operating Comparison Summary
130 Mile
(One Way) Ferry Route Comparison
Projected Profit Performa
(All at 200 Passenger, 75%
Capacity, Fuel at $3.10 Gallon -US)
......Vessel
Type .......................Time/Trips...............Gross
Revenue.......Fuel Cost.........Profit
Contribution/Trip
Nirvana Class Hydro Lance – 75 Knots
(200 Passenger Load)
.................4 Trips........................$46,400.................$11,688.....................$34,712
Mestral
Class Catamaran – 32 Knots
(200 Passenger
Load)..................2 Trips
.......................$23,200.................$11,676....................$11,524
Mono-hull
Ferry -24 knots
(200 Passenger Load)…...............1
Trip.........................$11,600.................$
3,704....................$ 7,896
Profit By Passenger Hourly/Miles…
310 Capacity Passenger Ferries,
130 Mile Route
200 Passenger Off-Peak Averaged Occupancy
Hourly
Vessel Type............Revenue.......Fuel
Cost Each.........Expense..........Passeger
Mono-hull.................... $10.74.................$
3.42.....................$3.94..................$ 3.40
CAT.............................$14,50................$
7.29......................$4.42..................$7.21
Hydro Lance............$34.11.................$
2.14.....................$4.15..................$27.82
Engine
overhaul is expensive for ferry operations. The most significant cost
is the lost revenues due to down time during these maintenance periods.
The operating time of diesel and gas-turbine engines approximates 10,000
to 15,000 hours between overhauls. At this time of overhaul, there is
usually one to two months required to complete all scheduled
maintenance. While this is a common requirement to all vessel types,
there are important differences.
During 10,000 hours, the exampled mono-hull vessel will have
traveled 240,000 nautical miles, the catamaran will have traveled
320,000 nautical miles and the Hydro Lance will have traveled 750,000
miles. Based on 12 hours of engine operation per day, each vessel will
require an overhaul of the engines every 25 months, but the distance and
revenue generated is substantially different. Scaleable to any size,
the HARTH Technology is to become a paradigm shift in transoceanic
surface transport.
And There Is
So Much More ...
 
Fast Ocean
Ferry Conversion, Retired Airliner Larger
HARTH RO-Pax Fast Ferries
Super-Fast HARTH Theme Ferries
HARTH Large Stable Ocean Platforms
You may
'mouse
click' any
underlined
phrase
or
any image above
and/or the
Light-Bars
below
for further information ...
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