Technological learning for resource efficient terawatt scale photovoltaics
Cost efficient climate change mitigation requires installing a total of 20–80 TWp photovoltaics until 2050 and 80–170 TWp until 2100. The question is, whether the projected growth is feasible from a resource point of view – and if so, under which conditions. We assess demand for fundamental resources until the year 2100, which are necessary independently from the specific nature of the used PV technology, i.e. energy, float-glass, and capital investments, and addtionally silver. Without technological learning serious resource constraints will arise. On the other hand, continued technological learning at current rates would be sufficient to stay within reasonable boundaries. With such technological learning, energy demand for production will correspond to 2–5% of global energy consumption leading to cumulative greenhouse gas emissions of 4–11% of the 1.5 °C emission budget. Glass demand might still exceed current float-glass production, requiring capacity expansion; and silver consumption could be kept at current levels. Installations costs would be 300–600 billion $US2020 per year. Technological solutions enabling such learning are foreseeable, nevertheless current and future investments must not only be targeted at capacity expansion but also at upholding the currently high rate of innovation.