You can use the BRDFLight Emissive material as a light source assigned to an object. Increasing the Value of the Value of the color affects the GI solution and produces more light. Note that overbright colors may look the same as pure white but the GI results is different.
If you know the photometric power of a self-illuminated object in lumens (e.g. 1700 lm for a 100-watt bulb) you can calculate the multiplier for BRDFLight if for the Emissive material if you divide the lumens by the surface area of the object in meters, provided that the self-illuminated color is pure white.
The direct illumination options currently only work properly if the BRDFLight Emissive material is the only material applied on the object. They will not work if the material is part of a complex material like a VRayBlendMtl Blend material. This restriction will probably be removed in a future release.
