Outposts Question - better to spend 20 or 60 energy?

I’m trying to calculate the cost of energy with the gain of mats I need to upgrade my gear.

I need a couple of more 15 ores but Outposts at 20 energy give 6 ores each while the 60 energy cost gives me 9. I usually have around 120 energy give or take. Sometimes more.

My calculations show it’s better to grind the 20 cost as I can get 4 upgrades while 60 can only get me 2/3 upgrades.