Abstract

The concept of primary energy is fundamental in energy economy and ecology. However, even in the specialized literature there is still no consistent usage of this concept. We shall present a wide-spread concept that can be considered as the original concept of primary energy. But, examining primary energy statistics, we shall find that the usage of the term >primary energy primary energy< even in the specialized literature originated from the problem of coping with the renewable energies using the conceptual instruments that were developed for an energy system based on fossil and nuclear fuels.