So, assume we're all imperial military planners, who have just been told about the ST Galaxy, and we now have a couple of weeks to work on our scandocs and have a detailed plan to present to the Emperor on how we will conquer the ST Galaxy and spread Civilization to the barbaric races (TM).
What kind of planning assumptions do we go on? How often do we need to refit a ship? How long between refuellings can we run our ships? How many ships do we have to leave behind in each conquered system? How many Sector Armies should we allocate to each planet? etc etc.
I'm assuming also that some basic first contact has taken place, a random feddy, romulan, or whatnot ship has been seized and boarded, so that as planners, we're aware of the limitations of warp drive -- it lets us actually have clearly defined frontlines, we don't have to worry about sneak hyper attacks in our main supply systems.
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Some basic data for our planners:
Fuel
It's said on the back of the Black Ice Sourcebook that 1 billion metric tons of starship grade fuel can power an "Imperial Main Battle Fleet" for a year.
We'll assume it's referring to a Superiority fleet as mentioned in the Imperial Sourcebook, with six ISDs and 390 combat starships. Sector Groups are about four superiority fleets (24 ISDs and 1,560 combat ships), which means if you want to run a single sector group, you need to supply it with about four billion metric tons of fuel a year.
Land vehicle data is kind of hard to come around; but we can assume that in combat; a vehicle probably consumes about 800 liters of fuel a day; which would be 0.8 m3 a day; and at the density of starship fuel (see below); that's about 836 kg of fuel a day for each major combat vehicle (Juggernauts, AT ATs); - but most vehicles in an Imperial army would be much lighter; and probably consume about 50 kg of fuel a day. This basically means an Imperial Sector Army in sustained full scale combat would consume 15,000 metric tons of fuel a day.
Food
The average American in 1995, consumed the following each year (LINK)
198 lbs of grain products
192 lbs of meat (red meat, poultry, and fish)
234 and 238 eggs per year (40-45 lbs of eggs basically)
24 gallons of milk (200 lbs)
65.6 lbs of fats/oils
21.8 gallons of coffee (180.94 lbs)
8 gallons of tea (66.4 lbs)
52 gallons of soft drinks (430 lbs)
12 gallons of bottled water (100 lbs)
22 gallons of beer (182.6 lbs)
About 1,656 lbs of food is needed for each Imperial; and if we add 30% to that to account for packaging weights, e.g. milk would be shipped on pallets, stuff like that, plus container weights; you'd need to move 2,152 lbs (about 1 metric ton) of stuff to keep one guy supplied each year. THis does not take into account the other stuff he'd want, like "I want a computer, I want a uniform", etc; but they'd be inconsequential basically next to his food requirements, unless he wanted a new landspeeder shipped over.

Ship Basic Logistical Data (only modern ships shown):
Command Ships
Executor: (280,734 crew, 38,000 troops; 318,734 total); 6 years consumables.
Heavy Battleline
ISD (36,810 crew, 9,700 troops; 46,510 total); 6 years consumables.
Medium Battleline
418 Cruiser (2,783 crew, 80 troops; 2,863 total) 1.2 years consumables
Strike Cruiser: (1,972 crew, 340 troops; 2,312 total) 1.5 years consumables
Escort Carrier: (3,485 crew, 800 troops; 4,285 total) 9 months consumables
Average: 3,153 crew; 1.15 years consumables
Light Battleline
Nebulon B Frigate: (920 crew; 75 troops; 995 total); 2 years consumables
Picket Line
Corellian Corvette (165 crew); 1 year consumables
Corellian Gunship: (91 crew); 8 months consumables.
Average: 85 crew; 0.55 years consumables
In-System Craft
System Patrol Craft: (12 crew, 10 troops; 22 total); 3 months consumables
Skipray Blastboat: (4 crew); 1 month consumables.
Average: 9 crew; 0.11 years consumables.
Roughing out the Food Requirements of a Sector Fleet
24 x ISDs = 1,116,240 metric tons of food every six years.
400 x Medium Battleline Ships:1,261,200 metric tons of food every 1.15 years
500 x Light Battleline Ships: 497,500 metric tons every 2 years
700 x Picket Line Ships: 59,500 metric tons every 6 months
Food requirements every six years: 9,906,204 metric tons
Basic Organizational Data
Sector Army
1,180,309 personnel
66,640 repulsorcraft/light vehicles
13,992 heavy vehicles
Sector Group:
24 ISDs
1,600 combat ships
800 auxilaries
2,424 ships total
Plus One Squadron under Moff's Personal Command (14 to 60 ships) attached to Sector Group HQ.
NOTE: Politically connected Moffs like Tarkin or Carlinson can have 15 extra squadrons attached for 225 to 900 extra ships to do what they want.
Deepdock Fleet
2 x Deep Dock Complexes
1 x Force Escort Systems Force (108~ warships)
280 Support Vessels
NOTE: The Smallest deepdock complex has three work bays, the largest of which can hold a Victory Star Destroyer with the other two able to accommodate any ship smaller than a carrier.
The biggest deepdock in service has 125 work bays, each big enough to hold a strike cruiser. You can combine them -- four bays can repair/build a VSD, 15 can combine for an ISD, and 18 to do a torpedo sphere.
Support Fleet
500 vessels in total
of which 125 are Corvette Sized or Smaller
of which 125 are Field Secured Container Vessels (FSCV)
NOTES: FSCV's travel in pairs, and a single force sphere on a FSCV is 800m in diameter can hold 250 million m3 of space. (actually sphere volume is 268 million m3; but you need room for access tunnels). Typical chainings of 20~ spheres on a FSCV are common.
NOTE II: On Black Ice class ships, which typically carry nine spheres, the sphere diameter is 600m, with 113 million m3 of space, of which if we go by the scale of the FSCV, only 105.09 million m3 is available for cargo. Each sphere holds about 110 million metric tons of refined fuel for power cells. This suggests that the density of refined fuel in SW is about 1046.72 kg/m3.