The amount of energy stored per energy level can be a fraction of energy available at one trophic which is transferred to the next trophic level. The fraction has an average of 10% but can vary between 1-15%. In general biomass and numbers of organisms decreases as one ascends the food chain.
Energy storage is the capture of energy produced at one time for use at a later time. The accumulator is a device which stores energy. There are forms in which energy can come from. For example; gravitational potential, electrical potential, chemical and radiation, kinetic latent and electricity. Converting energy from forms that are difficult to store in more economically storable forms involves energy storage.