Thanks for the replies guys,
Im a bit miffed at visible light being the reference. Correct me if im wrong but, the sun sends out a lot more IR and Radio than it does UV and xrays etc, additionally a large portion of the higher frequency radiation gets absorbed by our atmosphere.
So the majority of solar radiation that actually reaches the surface of the Earth is of UV and lower frequencies, therefore averaging it out it seems more longer wavelengths reach the surface than short...