Soon coal burning plants will be shut down and replaced with solar and windmill farms. Some say silver will be in great demand as large scale plans are in place for solar farms which involve large quantities of silver.
http://online.barrons.com/article/SB50001424053111903964304577418621009072772.html?mod=BOL_hpp_oe
http://etfdailynews.com/2012/05/23/is-it-time-to-buy-coal-stocks-coal-etfs-are-at-52-week-lows-kol-pkol-pcx-btu-joy-anr/
...developing...