In accordance with Ikey (https://www.reddit.com/r/SolusProject/comments/7ge9q4/x86_energy_perf_policy/dqijl8n/) I'd like to ask for the inclusion of the x86_energy_perf_policy package.
The package is already available here: https://dev.solus-project.com/D543

I added it to the current linux-tools package.yml and rebuild the package. Seems to work, e.g. package recognized by tlp, cpu enters "powersave" state when on battery (Thinkpad X220T).