The energy cost of amorphous silicon solar cells

Input energy analysis of flexible solar cells on textile

“…The high percentage of non-renewable energy supply causes problems in manufacture of renewable devices, because these devices gain a high EPBT through the embedded fossil fuel consumption [3,14,15]. EPBT indicates performance of a device by considering the energy generated against the primary energy used, during the whole lifetime, which will indicate whether or not a renewable energy device can repay the energy it required to be manufactured before reaching its end of life [1,2,16]. The EPBT is often used to measure performance of a PV device [2] and is also a marketing argument, as a low EPBT refers to a better product performance and should gain a stronger position in the market for PV devices [10].…”

“…Our early energy analysis of a simple small area amorphous silicon cell on glass [16] also included the significant energy embedded in the single-substrate production machinery (about 2 MJ of primary energy for each 25 cm 2 cell). However, in a continuous production process the energy per cell is reduced both by the energy consumed during process steps and by the higher throughput of the machinery.…”

“…However, in a continuous production process the energy per cell is reduced both by the energy consumed during process steps and by the higher throughput of the machinery. Using a similar estimation for continuous processing to that in [16] suggests a much lower ‘machinery’ primary energy cost of ∼13 MJ/m 2 which is not included in the total energy consumption below.…”

Energy pay‐back time: methodological caveats and future scenarios

“…The adoption of energy pay‐back time (EPBT) as the de facto standard metric for the energy performance of photovoltaic (PV) systems ensues from a time when the first commercial modules were very energy‐intensive to produce, and obviously, this had serious consequences on their associated environmental impact and impaired the credibility of PV as a truly viable ‘green’ alternative . As a result, the most common preoccupation at that time was that of testing whether, and how quickly, the complete PV systems would be able to ‘pay back’ the same amount of energy that was required to manufacture and operate them.…”