I for one do believe we should invest in exploiting these alternatives but the reality if things is economics.
People will buy whatever is cheapest and if oil is forced to compete with alternatives, it is a big enough industry to absorb a cost decrease, gasoline prices will get cheap again. Those of us who tend to watch our finances, (which is most of us), will buy gasoline.
This will result in investors fleeing the alternative energy market like rats fleeing a sinking ship and thus oil will monopolize the energy markets once again. The cycle will continueonce again.