America need refuelling every 3 months at sea each month if they were in combat, Gerald Ford need 1 refuelling every 25 years...Of course the one that G R Ford did would be expensive, but then you only do it once every 25 years. The cost for a G R Ford class refuelling is unknown, but it took $658 millions to refuel a Nimitz class.
"The [Nimitz class] ships are capable of operating for over 20 years without refueling and are predicted to have a service life of over 50 years."
https://en.wikipedia.org/wiki/Nimitz-class_aircraft_carrier
So, essentially, yuou build it, sail it for 25 years, refuel it and sail it for another 25 years. Hence the (calculated) annual cost of
refuelling a Nimitz would be $658 millions divided by 40-50 years i.e. $13.2 to $16.4 per year.
Now consider:
"The USS America (LHA-6) and the USS Tripoli (LHA-7) are part of what the Navy calls its now-in-development America-class amphibious assault ships designed with, among other things, a larger deck space to increase the ability to transport and utilized air assets, Navy Secretary Ray Mabus told an audience May 21 at the 2013 Energy Efficiency Global Forum, Washington, D.C. The ships are being engineered with a hybrid-drive propulsion system, meaning the ships can use diesel-electric propulsion as well as gas-turbine engines.
...
In fact, during its maiden deployment last year, the Makin Island’s hybrid propulsion system helped contribute to as much as $15 million in fuel-cost
savings over the course of the excursion, Mabus told the audience."
https://www.dodbuzz.com/2013/05/21/navy-developing-hybrid-electric-amphibious-assault-ships/
Go figure what annual fuel costs of the LHA were (obviously more than $15 million saved)
"At a ship speed of 12 knots, the initial fuel savings on the trip from the shipyard in Pascagoula, to the vessel’s home port in San Diego, CA around the southern tip of South America, fuel savings of over $18,000/day were reached as compared to steam turbines powering the vessel and its electricity producing generators. The gas turbines are calculated to offer 12% fuel savings compared to a steam plant. The electric drive offers 30% fuel savings compared to gas turbines and 43% compared to a steam plant.
The US
Navy expects over the course of the ship’s lifecycle to see fuel savings of more than $250 million."
https://www.marinelink.com/news/efficient-island-proven350998
Wasp class LHD:
"in the year 2019, there will be 8 steam ships left in the Navy; 2 submarine tenders and 6 LHD class ships . The LHD class will continue on in the Navy’s inventory through roughly 2040.
Steam plants require more parts, more personnel, more maintenance, and more fuel than many other propulsion systems
...
Once the seven ships in the LHD class are converted, the cost savings, mainly manning and fuel related, over the life
of the LHD ships should be in excess of $670 million USD (2005)
...
Fuel Cost ($M/yr) $11.73 million/yr"
http://web.mit.edu/2n/Abst-ExecSum/2007/Conversion/LHD.pdf
There have been at least a couple of GAO reports on the "break even point" for the cost of fuel between nuclear and "conventional" propulsion. In general, the larger the ship, the lower the break even cost for oil. (In other words, the larger the ship, the more cost effective nuclear propulsion was.)
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Nuclear Propulsion
A third strategy for reducing the Navy’s dependence on oil would be to shift to a greater reliance on nuclear propulsion.
2005 Naval Reactors Quick Look Analysis
A 2005 “quick look analysis” conducted by the Naval Nuclear Propulsion Program, also known as Naval Reactors, concluded that total life-cycle costs (i.e., procurement plus life-cycle operating and support costs) for nuclear- and fossil- fueled versions of large-deck aircraft carriers would equalize when the price of diesel fuel marine (DFM) delivered to the Navy reached $55. The break-even figures for LHA/LHD-type large-deck amphibious assault ships and large surface combatants (i.e., cruisers and destroyers) were $80 and $205 per barrel, respectively.54 As of February 2006, the price of DFM delivered to the Navy was $84 per barrel. Since the cost of DFM delivered to the Navy is roughly 15% greater than that of crude oil, these figures correspond to crude-oil costs of about $48, $70, and $178 per barrel, respectively. The difference in the break-even points results in part from the different amounts of energy used by each type of ship over its life time.
The Naval Reactors study was based on a 40-year ship life, which is roughly consistent with the expected service life of an amphibious assault ship, but five years longer than the 35-year life the Navy now plans for its cruisers and destroyers. If the calculation were done on a 35-year basis for the surface combatants, the break-even figure for those ships might shift somewhat.
The results for the surface combatants are for a ship roughly equal in size to the Navy’s past nuclear-powered cruisers (CGNs). Since most of these CGNs were smaller than the 14,500-ton DDG-1000/CG(X) design, the break-even point for a nuclear-powered version of the DDG-1000/CG(X) design might be somewhat different, and perhaps somewhat lower.
The study did not attempt to quantify the mobility-related operational advantages of nuclear propulsion. These include the ability to transit long distances at high speeds (so as to respond quickly to distant contingencies) without having to slow down for refueling, the ability to commence combat operations immediately upon arrival in the theater of operations without having to first refuel, and the ability to maneuver at high speeds within the theater of operations without having to refuel. Nuclear-powered ships also lack the hot exhaust gasses that contribute to the infrared detectability of fossil-fueled ships.
Since this was a “quick look” study that excluded or made simplifying assumptions about certain factors, a more comprehensive analysis might be required to decide whether to shift from fossil-fueled large-deck amphibious assault ships or large surface combatants to nuclear-powered versions of these ships. The results of the quick look study, however, suggest that the option may be worth further exploration, at least for the large-deck amphibious assault ships. It may also be worth exploring the option for large surface combatants, particularly if oil prices are expected to rise from current levels, and if the operational advantages of nuclear propulsion are also taken into account."
54 U.S. Naval Nuclear Propulsion Program, briefing entitled “Nuclear and Fossil Fuel Powered Surface Ships, Quick Look Analysis,” presented to CRS on March 22, 2006. The briefers explained that the study was originally conducted in 2005.
https://www.history.navy.mil/resear...hip-propulsion-technologies-2006.html#nuclear
