Final energy is a term that refers to all energies delivered in a form ready to be used by the end user: a litre of lead-free petrol for the user's vehicle, the electricity available through the user's socket, etc.
Due to the many ways it can be used, final energy comes in many forms: e.g. electricity, thermal energy, mechanical energy
Final energy is but a mere fraction of the initial primary energy, once it is transformed into secondary energy, stored, transported and finally distributed to the end user.
In a short production/distribution circuit, for example, an individual solar water heater, the quantity of final energy is closer to the quantity of primary energy.
The electricity consumed to produce this lamp's light is a fraction of the primary energy actually used: final energy. © Mattia Luigi Nappi, Wikimedia CC by-sa 3.0