▁power ; ▁com pressed ▁air ▁is ▁commonly ▁used ▁to ▁operate ▁p neum atic ▁tools ▁in ▁fact ories ▁and ▁repair ▁gar ages . ▁A ▁p neum atic ▁w rench ▁( for ▁instance ) ▁is ▁used ▁to ▁remove ▁and ▁install ▁autom ot ive ▁t ires ▁far ▁more ▁quickly ▁than ▁could ▁be ▁done ▁with ▁standard ▁manual ▁hand ▁tools . ▁ ▁A ▁p neum atic ▁system ▁was ▁proposed ▁by ▁pro ponents ▁of ▁Ed ison ' s ▁direct ▁current ▁as ▁the ▁basis ▁of ▁the ▁power ▁grid . ▁Com pressed ▁air ▁generated ▁at ▁Ni ag ara ▁F alls ▁would ▁drive ▁far ▁away ▁gener ators ▁of ▁DC ▁power . ▁The ▁war ▁of ▁the ▁curr ents ▁ended ▁with ▁altern ating ▁current ▁( AC ) ▁as ▁the ▁only ▁means ▁of ▁long ▁distance ▁power ▁transmission . ▁ ▁Th erm al ▁power ▁ ▁Th erm al ▁power ▁can ▁be ▁transport ed ▁in ▁pip elines ▁containing ▁a ▁high ▁heat ▁capacity ▁fluid ▁such ▁as ▁oil ▁or ▁water ▁as ▁used ▁in ▁district ▁he ating ▁systems , ▁or ▁by ▁phys ically ▁transport ing ▁material ▁items , ▁such ▁as ▁bott le ▁cars , ▁or ▁in ▁the ▁ice ▁trade . ▁ ▁Chem ical s ▁and ▁fu els ▁While ▁not ▁techn ically ▁power ▁transmission , ▁energy ▁is ▁commonly ▁transport ed ▁by ▁sh ipping ▁chemical ▁or ▁nuclear ▁fu els . ▁Possible ▁artificial ▁fu els ▁include ▁radio active ▁is ot op es , ▁wood ▁alco hol , ▁gra in ▁alco hol , ▁m eth ane , ▁synth etic ▁gas , ▁hydro gen ▁gas ▁( H 2 ), ▁cry ogen ic ▁gas , ▁and