Talk:Banshee Chorus Helmet/@comment-172.73.234.210-20160907192425/@comment-30863195-20170828122820

The energy drain for channeled abilities is given by

max(base_cost * (200 - power_efficiency) / power_duration, 0.25 * base_cost)

For example, with r5 Streamline and r5 Fleeting Expertise, the energy drain is minimized at 25% of the base cost.