"Alternative" energy sources certainly present possibilities for a sustainable energy future. If we can find ways to use wind, solar and tidal forces to produce enough energy to serve the needs of society, we can also start to see ways to continue to live as we currently live. Without such a view of alternative potential, continuing to live as we do now seems less likely, as we will at some point run out of petroleum.
I agree with mwalter that finding and using renewable energy is expensive and it will take some time before there is some real change. However, I think it's something that should be made a priority.
One argument that you could use in support of renewable energy is that, for America, it could be our solution to energy independence. Currently, we rely heavily on other countries for oil. This puts us in a a difficult situation. If we can find and use renewable energy in a sustainable and affordable way, we will no longer have to depend on foreign oil.
There can be no doubt that eventually we are going to run out of oil and coal and all traditional sources of energy. The problem is getting people to invest the time and money on the development of renewable resources. Because it's expensive and there is so much money and power tied up in traditional energy sources, we aren't going to make significant progress until there is a real energy crisis. The higher prices that we have to pay at the gas pump from time to time are not enough to bring about meaningful change.
So the best we can do is position ourselves to be ready to make the transition to renewable sources once oil and coal really do run out. First, there will have be a major crisis.
In reply to post #2 and #3 Thanks for your suggestions.