To combat the massively detrimental effects of climate change, the world will have to stop emitting carbon dioxide and will even have to move to negative emissions in the next few decades. This will entail totally decarbonizing the world’s energy system and transforming how the world uses energy and other resources to produce everything that is needed to sustain society as we know it. Photovoltaics (PV) will play a major role in this newly decarbonized world that should be realized in a very short timeframe of only three decades [1]. It has been estimated that collectively, the world needs to install between 60 and 70 TW of PV in that timeframe which is a massive undertaking considering that currently there is approximately 1 TW installed. It also begs the question whether there are economically sustainable trajectories to reach this goal, whether there are ways to speed up this process, and whether this can be done in a sustainable fashion. In this presentation, we will explore whether there is an economically sustainable way to ramp up PV production capacity to produce the needed 60+ TW of installed capacity.[2] All the while still ensuring that manufacturers continue to make rational decisions towards investing in production capacity and avoid stranded assets after the relative short period of three decades is done. The modeling presented considers increased learning and continued improvements in design of PV and manufacturing as well as limits to learning having to do with embodied energy. The scale-up challenge is considerable as the massive and needed ramp up in production capacity of the next few decades will be followed by very modest demand for new PV driven only by needed replacement of existing panels and continued population increases. We demonstrate that this ramp up followed by ramp down is possible and calculate the base-line cost of this ramp up in production capacity and also calculate the cost of the PV needed as well as discuss the scale of natural resources needed and the challenges associated with what happens to the panels that need to be replaced.[3] We also consider what happens if a new technology such as high-efficiency tandems based on perovskites or other materials gets introduced during the carbonization period, and show that this can make a sustainable trajectory more likely and make it cost less than continuing along existing technology pathways. Such new technologies can also significantly reduce the needed capital to build the necessary manufacturing capacity, lower the needed installation area and resources, and decrease the total embodied energy.