It would be a far more compelling argument if there were actual numbers in there showing that for those kinds of loads Java does in fact require more wattage; f

It would be a far more compelling argument if there were actual numbers in there showing that for those kinds of loads Java does in fact require more wattage; for long-running processes, once the VM has JITed everything down to machine code, one might reasonably expect that it would be pretty close to the consumption of a natively compiled C++ application. He could turn out to be right, I just don't think you can take it as self-evident that the Java VM must be using more power.