Hence greening is a systemic challenge and requires actions along the whole value chain, as evidenced in research by Kemp et al., ( The findings show clear signs of more energy-efficient investments being made in crop-drying methods. If energy use in the value chain as a whole is considered, however, drying technologies represent only a trivial component. The energy wasted in inefficient logistics (for example, dirty diesel combustion in the trucks hauling produce from farm to drier)— in part, a result of subsidized fuel—is far more than any marginal gains in the crop-drying component and has largely been ignored in the greening policy agenda. In many advanced economies, final markets demand the greening of value chains, and that is increasingly the case for middie-income markets in Africa and other emerging economies, a process sharpened by the rapid advance of global supermarket chains in Africa and elsewhere.