This paper examines some of the investment implications of what is called the "great transformation" by which renewable sources of energy replace the current reliance on carbon-based fuels. To set the stage, the paper begins by presenting detailed data on past, current and forecast future energy usage. The data imply that the great transformation will be very expensive. The paper then turns to the question of how the transformation will be financed. It is argued that the political environment will be an important determinant of the financing form.