ABSTRACT
This chapter outlines some of the progress toward developing several historically slow-moving technologies and highlights these as bottlenecks in the development of other technologies. A fuel cell is an electrochemical device that produces electricity from an external fuel supply; it is a nineteenth-century technology. Technical development presently takes the form of larger generators with increasingly efficient gear trains, taller windmills, and the capacity for generating power with lower-velocity wind conditions. The problem of intermittency will persist until a technology for economical intraday power storage becomes available in the case of solar power. The large-scale solar installations are essentially daytime peaking facilities. For storage of power from intermittent power sources, such as wind and solar, at the scale of the power grid, flow batteries offer some promise for the future. The flow battery in its various versions has obvious applicability in which the large battery is teamed with intermittent power sources, such as solar and wind.
