Found this popped for me when only completing one branch of a tree and not the whole tree/skill category. By far the cheapest way of unlocking this is
upgrading the left side of Energy Management:
ATP Recycling (82 Neuropolymer)
Energy Density (34 Neuropolymer)
Greedy Guts (146 Neuropolymer)
Total: 262You can do a manual save before buying these upgrades if you want to get the Neuropolymer back to spend elsewhere.