How does a light shelf model work in EnergyPlus?

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Does light shelf work like a shading object limiting solar energy to hit and transmit to windows thus affecting window solar gains?

Does light shelf have reflectance( which is equal to reflectivity ) that allows light to be reflected to the clerestory into the ceiling onto the work-plane?

I wanted to investigate illumination and daylighting by light shelves in EnergyPlus instead of using Radiance since I will also be assessing its energy impact on the building.