Example:
15 GW*h = 1.289768e+10 calorie (nutritional)
1 GW*h = 859845227.858985 calorie (nutritional) | 1 calorie (nutritional) = 1.163e-9 GW*h
Conversion Steps:
15 × (3.6e+12 / 4186.8) = 1.289768e+10