Higher values will make indirect lighting brighter.
A value of 1.0 represents physically accurate behavior, but higher values
can be used to make indirect lighting propagate more visibly when using
a low number of bounces.
This can be used to speed up bake times by lowering the number of bounces
then increasing the bounce indirect energy. Unlike BakedLightmapData's
energy property, this property does not affect direct lighting
emitted by light nodes or emissive materials.