I figured to summarize the available free renderers for Blender.
Please feel free to correct me or add suggestions, thanks.
In alphabetical order:
— D5 Converter for Blender
- Octane ¹
- Renderman ¹
- TheBounty (YafaRay fork) ²
¹ Free with certain restrictions.
² At the time of writing this renderer is not yet available for Blender 2.8
(please let me know if I’m mistaking or if this has changed).
I also wrote an article with more info about the available free renderers: