Scattering - Absorption - Refraction - Reflection - Transmission.
You don't "increase" light intensity. That's more like a god thing, not glass.
Regarding the heat.... terms above, then you can also explain the "increase" in heat.
Somehow one doing "experiments" (hurts to call it that) should agree that the main laws of thermodynamics are not to be disputed - at least the first one, The rest are way harder to get.