Do you have any clue the volume of air that would be required to replace even one turbin at say Hoover Dam? Here is an assist. Hoover has 17 turbines and uses 32,000 cubic ft. pr. sec. Thats 1,882 cfs per turbine. Multiply that by 770 (density ratio) and you get 1.5 million cfs. If you could build such a thing (not) you would get 2.35 gigawatts per year. US uses maybe 4.5 billion gw pr. yr. IF you master the technology you will need 192 MILLION mountains to hollow out...not "130". The hydrogen conversion is another matter. Good luck.

Do you have any clue the volume of air that would be required to replace even one turbin at say Hoover Dam? Here is an assist. Hoover has 17 turbines and uses 32,000 cubic ft. pr. sec. Thats 1,882 cfs per turbine. Multiply that by 770 (density ratio) and you get 1.5 million cfs. If you could build such a thing (not) you would get 2.35 gigawatts per year. US uses maybe .45 billion gw pr. yr. IF you master the technology you will need 192 MILLION mountains to hollow out...not "130". The hydrogen conversion is another matter. Good luck.