Generative goods are 'goods' which increase with use. Trust, love, ideas, friendship are all examples of generative goods. They contrast with economic goods which are scarce and diminish with use. If two people trust each other their trust doesn't diminish with their stock of trust being used up but increases, likewise when an idea is shared it tends to increase as it is added to through discussion.
Social energy is a generative good and is a key resource in a people's movement. It has to be managed carefully alongside economic goods. Leaders of people's movements need to develop the skills to manage both of these types of resource effectively.