About wind generated electricity; in the early 90s NPRs Morning Edition interviewed a chap who had done the ## to suggest that if the UP put up turbines along the Wyoming main, they would have available enough kwh to power the entire freight tonnage of the UP,(including MP, WP, but not the since acquired SP, D&RGW, C&NW. Former SP/D&RGW owner P. Anschutz--not known as an enviro--is currently invested in a large wind farm project in Wyoming. As others point out, battery or hydrogen fuel cell engines/trucks will likely take over the branchline tasks but using electricity for the dense mainlines will save a huge segment of the CO2 emissions. Of course, reducing population is worthwhile as well.

As to copper costs, in 45+ years as an electrician I have been gouged by the commodity market off and on. Overall electric locomotives are more efficient if only for not carrying around tons of diesel prime movers, fuel, and going electric means passing Tier 4 pretty much automatically, getting rid of fuel pads, and longer service lives between rebuilds.