Renko bars are constructed by removing the time information from the price curve. You can only see a trend direction, but not its steepness or its acceleration and deceleration. So your algorithm gets less information and consequently will be less profitable than with a real price curve.

Renko bars are meant as a visual aid, with the idea of not getting distracted by the dents and ripples in a curve with real bars. They are not meant for automated trading. A computer won't get distracted by dents and ripples and thus has no use for Renko bars.