Energy return time / Energetic amortisation

The energy return time or energetic amortisation describes the time, which must run a power producing plant, in order to return the energetic manufacture costs. Although here 3 to 4 years with photovoltaic plants sounds like a long time, they are substantially smaller with the emission-afflicted plants and atomic power plants and in addition substantially cleaner. If a plant paid the manufacture expenditure off, it is called a positive energy balance.