Carbon footprint of electricity transmission: insights from a Brazilian case study

Abstract

Electricity grids play a crucial role in electricity systems worldwide and will become even more critical as the transition to clean energy advances. In this regard, reducing greenhouse gas (GHG) emissions associated with electricity transmission is crucial to supporting carbon reduction goals and achieving carbon neutrality in light of the escalating climate concerns. This paper aims to quantify the carbon footprint of transmitting electricity through a case study of a transmission line in Brazil (BR-TL). For this purpose, we developed a comprehensive electricity transmission scenario using the ANAREDE software. Additionally, our analysis is derived from data obtained through both primary and secondary sources concerning relevant inputs and outputs considering the construction, operation, and decommissioning stages. As a result, transmitting electricity through the BR-TL transmission line results in 10.89 gCO₂eq. per kWh delivered. Notably, the operation stage is responsible for over 67% of these GHG emissions, predominantly due to energy losses during electricity transmission and associated with the electrical substation transformers. Our results also highlighted the relevance of the construction stage, contributing more than 32% of the carbon footprint, which is mainly linked to GHG emissions resulting from land use change. These findings offer valuable insights for future electricity transmission infrastructure development, aligning with national climate targets and supporting global decarbonization efforts.

Keywords

Electricity transmission / transmission line / electricity / carbon footprint / climate change

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