A method for drilling a well includes applying energy input to a drill string (31) by at least one of rotating the drill string (31) from surface and operating a drilling motor (41) disposed in the drill string (31) to operate a drill bit (2) at a bottom of the drill string (31); an amount of the applied energy not consumed in drilling formations caused by at least one of motion, deformation, and interaction of the drill string (31) is calculated; an amount of the applied energy used to drill formations below the drill bit (2) is calculated; and at least one drilling operating parameter is adjusted based on energy calculation before or during drilling operation.