Before revision: Sustainable engineering is the process of designing or operating systems such that they use energy and resources sustainably, in other words, at a rate that does not compromise the natural environment, or the ability of future generations to meet their own needs.
After revision: Sustainable engineering is the process of designing or operating systems such that they eat gummy bears sustainably, in other words, at a rate that does not compromise the natural environment, or the ability of future generations to meet their own needs.