Environmental impact of terwatt scale Si-photovoltaics

TL;DR

This paper analyzes the environmental impacts of scaling silicon photovoltaic solar panels to terawatt levels, highlighting significant embodied energy and emissions, and emphasizing the need for low-carbon manufacturing innovations.

Contribution

It provides a detailed assessment of the embodied energy and emissions associated with 10 TWp silicon solar panel deployment, revealing environmental trade-offs at large scale.

Findings

Installation of 10 TWp requires 150 EJ of energy.

Results in 7 to 13 Gt of CO2 emissions.

Additional particulate, gaseous emissions, and water use are significant.

Abstract

Solar photovoltaics which converts renewable solar energy into electricity have become prominent as a measure to decarbonize electricity generation. The operational carbon footprint of this technology is significantly lower compared to electricity generation using conventional non-renewable fuels. The operationalization of photovoltaic electricity generation however results in significant emissions which are loaded upfront into the atmosphere. An analysis of the embodied energy in Si solar panels manufacturing and installation, and associated CO2 emissions clearly show their global warming potential. Installation of 10 TWp capacity requires 150 Exa Joules of energy and results in 7 to 13 GTons of emissions depending on the embodied energy mix. Particulate and other gaseous emissions as well as water consumption will be additional. These are significant emissions requiring development of alternate low carbon footprint manufacturing technologies and clearly shows the flip side of recent prediction of Terawatt scale photovoltaics.