* Elected officials want bitcoin miners to move to Kentucky * By some estimates, Kentucky has become a national leader in bitcoin carbon emissions * Tax breaks and incentives for miners spark controversy (Adds information throughout on Kentucky State Senator Brandon Smith's involvement in Biofuel Mining Inc.) By Avi Asher-Schapiro BELFRY, Kentucky, March 15 (Thomson Reuters Foundation) - In a ravine deep in the Appalachian mountains, Warren Rogers stands on the ruins of an abandoned coal-washing plant that used to prepare hundreds of tons of the fuel a day for transport through the tiny town of Belfry, Kentucky.