cable cables circuit clouds conduct construction consumer current danger electricity energy frame framework fuel generation generator grid industry infrastructure line lines metal national network overhead power powerline pylon science service silhouette sky station steel structure supply electric technology Tension tower transmission Utilities utility voltage volts wire abstract aged aging background brown chemical corroded corrosion damage damaged dirty distressed ferrous grunge grungy hull industrial iron macro metallic old oxidation oxide paint peel peeling pitted plate reaction red retro rough rust rusted rusty scrap stain stained texture urban weathered weathering