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Why would there be a last mile problem if you were directly generating on base for synthesis? Solar and wind have the issue of land usage, in that the large la

Why would there be a last mile problem if you were directly generating on base for synthesis? Solar and wind have the issue of land usage, in that the large land requirements of renewables mean more land to secure. That and military bases do not have the luxury of being conveniently sited next to the best places for such things. It would hardly be the first environmental disaster happening on a military base. Even as recently as Iraq and Afghanistan: https://www.military.com/benefits/veteran-benefits/what-burn-pit-registry.html https://www.military.com/benefits/veteran-benefits/what-burn...

voakbasda 5y ago
I expect the military will be the among the first to deploy portable nuclear generation in containers. Then this process becomes an obvious win for these bases.
- dredmorbius 5y ago
  That's been tried. Even in non-combat environments (McMurdo Station, Project Iceworm), proved nuclear power solutions (adaptations of naval reactors used successfully in submarines) have proved nonviable. The risks of a reactor in a live-fire zone are ... considerable.
dredmorbius 5y ago
I'm not talking of last-mile in terms of fuel synthesis alone, but in terms of all logistics. Land-based actions have a last-mile problem in that to put and establish boots on the ground, they need to traverse that mile directly, and extend supply lines to that last mile. Tactical aircraft have an effective combat range measured in hundreds or thousands of miles. Mechanised infantry in miles or tens of miles. Foot soldiers in yards to miles. A Naval task force's operation is at sea, outside the effective range of virtually any of the opponents the US has faced in combat since WWII.[1] Aircraft and crew depart a carrier or other base, conduct a mission, and return to base, outside the area of engagment. The logistics chain occurs through what has been for nearly three quarters of a century non-hostile territory. An FOB is right in the stinkin' middle of the mess. It's within the area of engagement, supply lines move through hostile territory, are subject to ambush attacks, both by live opponents and remotely-activated or passively-triggered IEDs and mines. Total supply requirements are too great for aerial supply alone. That's the last-mile problem. At the same time, FOBs and other installations are subject to enemy attack, and large-scale renewables deployments and synfuel equipment would be attractive and viable targets for relatively simple attacks (mortars, drones, missles), which could easily degrade, disable, or entirely destroy such equipment. I'm unsure of what a major Army or Marine unit's fuel requirements are, but assuming a 40% conversion efficiency from sunlight and 8 hours at 200W per m^2 of PV array, creating 1 barrel of oil per day (42 gallons) would require on the order of 2,700 m^2 of PV array, or a square roughly 50 m on a side. A 100m square might provide 4 barrels/day. There might be some land-based operations which could support this, but I strongly suspect many could not. Actual solar performance would also likely be far lower, likely yielding only 25--50% of the output I'm listing here (spacing factor, overcast, and other standard reductions on nameplate capacity), even before accounting to combat-based degradation. ________________________________ Notes: 1. Five ships were lost to mines during the Korean war, the USS Liberty was scrapped after it was attacked by Israeli forces in 1967. The USS Cole was damaged, but not lost, in a suicide-bombing attack in 2000. Numerous other vessels have been lost largely through accidents and occasional sabotage (all by US nationals or service members). The USS Pueblo was captured intact in 1967. https://news.usni.org/2012/08/28/notable-us-navy-ships-lost-world-war-ii https://news.usni.org/2012/08/28/notable-us-navy-ships-lost-...
- bobthepanda 5y ago
  I suppose in the Air Force's mind, even a slight reduction in delivering fuel via tanker would be a significant cost savings. Either way, they're operating from land.

voakbasda 5y ago

I expect the military will be the among the first to deploy portable nuclear generation in containers. Then this process becomes an obvious win for these bases.

dredmorbius 5y ago
That's been tried. Even in non-combat environments (McMurdo Station, Project Iceworm), proved nuclear power solutions (adaptations of naval reactors used successfully in submarines) have proved nonviable. The risks of a reactor in a live-fire zone are ... considerable.

dredmorbius 5y ago

I'm not talking of last-mile in terms of fuel synthesis alone, but in terms of all logistics. Land-based actions have a last-mile problem in that to put and establish boots on the ground, they need to traverse that mile directly, and extend supply lines to that last mile. Tactical aircraft have an effective combat range measured in hundreds or thousands of miles. Mechanised infantry in miles or tens of miles. Foot soldiers in yards to miles. A Naval task force's operation is at sea, outside the effective range of virtually any of the opponents the US has faced in combat since WWII.[1] Aircraft and crew depart a carrier or other base, conduct a mission, and return to base, outside the area of engagment. The logistics chain occurs through what has been for nearly three quarters of a century non-hostile territory. An FOB is right in the stinkin' middle of the mess. It's within the area of engagement, supply lines move through hostile territory, are subject to ambush attacks, both by live opponents and remotely-activated or passively-triggered IEDs and mines. Total supply requirements are too great for aerial supply alone. That's the last-mile problem. At the same time, FOBs and other installations are subject to enemy attack, and large-scale renewables deployments and synfuel equipment would be attractive and viable targets for relatively simple attacks (mortars, drones, missles), which could easily degrade, disable, or entirely destroy such equipment. I'm unsure of what a major Army or Marine unit's fuel requirements are, but assuming a 40% conversion efficiency from sunlight and 8 hours at 200W per m^2 of PV array, creating 1 barrel of oil per day (42 gallons) would require on the order of 2,700 m^2 of PV array, or a square roughly 50 m on a side. A 100m square might provide 4 barrels/day. There might be some land-based operations which could support this, but I strongly suspect many could not. Actual solar performance would also likely be far lower, likely yielding only 25--50% of the output I'm listing here (spacing factor, overcast, and other standard reductions on nameplate capacity), even before accounting to combat-based degradation. ________________________________ Notes: 1. Five ships were lost to mines during the Korean war, the USS Liberty was scrapped after it was attacked by Israeli forces in 1967. The USS Cole was damaged, but not lost, in a suicide-bombing attack in 2000. Numerous other vessels have been lost largely through accidents and occasional sabotage (all by US nationals or service members). The USS Pueblo was captured intact in 1967. https://news.usni.org/2012/08/28/notable-us-navy-ships-lost-world-war-ii https://news.usni.org/2012/08/28/notable-us-navy-ships-lost-...

bobthepanda 5y ago
I suppose in the Air Force's mind, even a slight reduction in delivering fuel via tanker would be a significant cost savings. Either way, they're operating from land.