There are still some serious issues w/ hydrogen though. One, the stuff slowly corrodes most of the metals currently used in cars. Two, it's very light & will seep through most metals so we'll have to be using polymer or ceramic gas tanks eventually or we'll fill up one day & have it gone the next! Three, there is no infrastructure yet in place to deliver hydrogen nor is there likely to be within the next several years. Four, no giant lobbying groups exist or should I say, no groups as large as the farmers! Five, it takes a bunch of energy to obtain the hydrogen in the first place because it doesn't occur naturally.
Now solar, that's a whole different thread & I've expressed my opinions on that subject enough already!