Well, with all due respect, there is clearly more of a relationship between these two energy products than there is between Silver and Soybeans, lol. T. Boone Pickens could give a nice lecture on the subject as it is at the core of the Pickens Plan. A rising/surging crude oil price certainly creates more incentive to seek cheaper energy alternatives no matter how you slice it, whether it be wind, solar, nuclear or natural gas. So there are certainly relationships to explore between these products, especially on the demand side of the equation.
In any event, for those interested in pursuing the subject in greater depth, have a read of the excellent study published by the Baker Institute. It is lengthy and technical but worth the read when you can set aside a chunk of time for it.