Is it true that transitioning to alternative energy sources will not solve the problem?

The authors of The Energy Reader, Tom Butler, Daniel Lerch, and George Wuerthner, posit that our energy crisis cannot be solved merely, or even mostly, by transitioning to non-fossil fuel energy sources and by technoscientific innovation.  Their thesis is that no matter what we do, our growth makes relying on any current or yet-to-be-discovered energy sources impossible.  But is this truly the case?  Butler, Lerch, and Wuerthner explain why alternative energy sources like renewables and nuclear have many issues that would make relying on them difficult – low Energy Return on Energy Invested (EROEI), intermittency, lack of infrastructure, difficulty with storage.  However, they did not provide sufficient evidence that these sources, combined with one another and with further innovation in both obtaining energy and using it efficiently, cannot provide the amount of energy that our world currently uses, or will use in the near future.  In order to be convinced that this is the case, I would need to hear about countries that had maxed out their usage of alternative energy sources and still could not use them to obtain 100% of their energy.  Of course, this does not mean that I am convinced that these sources (combined with innovations) can avert the crisis without drastic population reduction.  I believe that it remains to be seen.

At this point, I agree with Butler, Lerch, and Wuerthner that continued exponential population growth is not feasible, but I think we can do more with alternative energy sources than they give us credit for.  I think that if we make appropriate changes in infrastructure and make more discoveries, we can serve the world’s energy needs for a while to come, even accounting for the fact that countries that currently do not use much energy (such as those in Africa) will most likely increase their energy usage.  It’s important to solve the population problem, but I think that alternative energy sources can buy us time to do that, and we are not necessarily destined for disaster.  Population is actually going down in many industrialized countries, so it is reasonable to guess that when currently nonindustrialized countries become industrialized, their populations will also decrease.  So it may be that the problem of population will in some sense solve itself.  Though, of course, we cannot assume that, and must apply the precautionary principle to the idea of choosing not to do anything active about overpopulation (and, in general, should apply to precautionary principle not only to projects we are considering starting, but also to continuing to do business as usual).