Role of negative emission technologies in South Africa's pathway to net zero emissions by 2050

Abstract

Achieving net-zero carbon emissions by 2050 is pivotal for South Africa to fulfill its commitments under the Paris Agreement and contribute to limiting global warming. However, South Africa faces several challenges due to its heavy reliance on carbon-intensive sectors. This study adopts the Global Change Assessment Model (GCAM-South Africa), an integrated assessment model, to evaluate potential strategies and implications for South Africa to attain net zero carbon dioxide (CO2) emissions by 2050. We also evaluate the role of novel negative emission technologies (NETs), such as bioenergy with carbon capture and storage (BECCS) and direct air capture with carbon storage (DACCS), as well as fossil CCS in meeting the net zero target. The results indicate that significant transformations, such as the extensive expansion of renewable energy, increased electrification, and gradual phasing out of coal, are necessary across South Africa's energy system to achieve net-zero emissions by mid-century. With the full deployment of NETs and fossil CCS, coal power generation is projected to decline by 85 % versus 99 % without implementation. The availability of NETs and fossil CCS also alleviates the pressure on the pace of renewable energy deployment and electrification. While BECCS has a higher potential to deliver negative emissions, relying solely on its extensive deployment presents trade-offs. Specifically, scenarios involving BECCS could decrease cropland and pasture by 59 % and 69 %, respectively, by 2050. Water consumption for bioenergy crop cultivation and bioelectricity with CCS is also expected to account for 2 % of total water use in 2050. Overall, this study emphasizes the need for South Africa to complement aggressive emissions cuts with NET and fossil CCS scaling while considering their implications for energy, land, and water. We offer valuable insights to inform strategic decision-making concerning mitigation technologies, sectoral transitions, and managing trade-offs on the pathway to a net-zero future for South Africa.