You're not comparing two similar treks.

We can show you the numbers, but we'd be doing you a disservice if we didn't say this first: Bijli Mahadev Trek and Shrikhand Mahadev Trek are not alternatives — they are different sports. One is a 1-day trek reaching 8,070ft, the other is a 7-day trek reaching 17,150ft. If you're choosing between these two, one of them likely isn't an option for you yet.