There is a global consensus that our path towards a greener future depends on finding ways to reliably integrate renewable energy sources into the generation pool of our power grids. This vision is accompanied by the challenge of making demand significantly more flexible in order to compensate for the intermittent nature of renewable generation outputs and keeping the demand and supply continuously balanced. It is apparent that deferrable energy requests will play an especially valuable role in this transition. While the idea of scheduling energy requests to follow a variable generation profile seems intuitively straightforward, there are several major challenges that need to be solved before deferrable loads become a reality in our power systems. In this paper, we discuss these difficulties and present a demand side management program we proposed, called Digital Direct Load Scheduling (DDLS). Further, we will present different scenarios under which demand aggregators can help power system operators integrate more renewables in the grid, shave peak demands and control wholesale prices of electricity.