In other words, the ability to purchase upgrades that increase the max energy you can have. For me it's the equivalent to hiring additional (but not better) scouts, low-level staff, or equipment. I would even go so far as to propose that it look something like this:
Level Energy Budget Price of upgrade (G)
0 80 NA (initial)
1 100 50K
2 110 150K
3 125 350K
4 150 750K
5 200 1500K
What do you think?
