In order to glean some insight into the likely trends in the next 50 years of power generation, the major trends of the last 50 years are reviewed first of all. It is noted that not only were all the power generating systems in operation today being researched in the 1960s, but so were most of those now being discussed for the future. The major trends in generation have all been driven by political and environmental considerations rather than by radically new ideas.For the next 50 years, in a new environment of concern about climate change and security of electricity supply, new technology must be developed to make some more of the options economically viable. This article surveys most of the systems now being considered and picks out a few of the enabling technologies. With such a broad subject, selectivity in the choice of sources is inevitable: this review draws preferentially upon papers published in the Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy over the last 10 years.