The prediction that Peak Oil premises all its gloom and doom on is that oil will become too expensive to use (as we do now). Its alot like Malthus' theory about agriculture, and population. However Technology is the big invisible input that breaks these pessimistic formulas down. Oil can become ever cheaper to extract, and ever more difficult and remote deposits become even more available. Peak Oil is also constantly basing its fear around the idea that there are few new deposits to be found, and the ones that could be available are not available due to security or poiltical concerns. Well, We know that there are plenty of new deposits being found, many countries that have not have reserves have found it (Israel, East Africa) in significant amounts. The world has gotten pretty peaceful, even in the darkest corners of Africa, most of the world is at peace. Angola was a country that was off the worlds markets because of security concerns, but that is a thing of the past. Tomorrow, Kenya, Tanzania, Uganda, Mozambique will all be oil producers. Even Somalia may yet have oil deposits that will be discovered when the government has become more powerful. There are still massive deposits that will be discovered. The frightful thing is that cheap oil means that we need a political consensus to get rid of fossil fuels at a drastic cost. It would be much easier if there was just an economic incentive. We dont price the costs of respiratory disease into the costs of fossil fuels at all, and we will have to as the costs of health care spiral upward. Governments are going to be desperate for more money to pay for the increasing numbers of seniors.
I dont think we could change 100% to renewables, nor is it desireable. We should have enormous amounts of nuclear power and electric cars, and renewables where it is optimal and possible.