Usually, a game of professional Go can be a very long affair, with both sides having 4-8 hours on their clock. In the phases between the actual plays, one could hear a pin drop. Hardly material for television broadcasts.
However, in "Lightning Go" (or haya-go in Japanese), the clicking of the stones on the board can sound like a hailstorm in full cry. Usually, a player has 30 seconds per play, with a given number of additional full minutes for complicated situations, usually ten. Speedy play is of an essence and it is legal - if not nice - to play meaningless moves in an attempt to make your opponent wast one of his valuable extra minutes.
Another method of lightning go is giving the players the additional time en bloc at the beginning, timed like in chess, and then go into byo-yomi, limiting each play to 30 seconds. However, this usually means that there is not much time to think in complicated spots later on, allowing for suboptimal plays, and inferior games. So at least in Japan, the first method is used.
Such games still run about 1,5 to 2 hours, they can be and are televised on TV, in tournaments such as the Japanese NHK Cup and NEC Cup or the Asia Cup. At these televised events, there are usually Go professionals, who comment on the game, show alternative moves and explain difficult decisions to the viewer, making these broadcast interesting to everyone interested in studying Go.