The amortisation period defines the time it takes for a photovoltaic system to produce the same amount of energy as that required for its manufacture. This is achieved by dividing the energy consumed in the production of the module by the annual energy output of the module.
In general, the amortisation period for the types of panels currently available on the market is less than two years in Central Europe. Thus, cells made of silicon, by far the most widely used on the Luxembourg market, have an amortisation period of less than two years; for thin-film cells, which are currently emerging on the market, this goes down to less than one year.