Tip o’ the blogger hat to Ben Laurie.
This book (Sustainable Energy – Without the Hot Air) takes a straightforward and fact-based approach to the question (of sustainable energy), summing up all the sinks of energy and possible sustainable sources, and seeing what works. The sad fact is, it seems, that not much does.
The book is also available for free in PDF form from the author’s website. But don’t forget that if you buy the book, you are sequestering carbon!