2022-08-08 カリフォルニア大学サンタバーバラ校(UCSB)
<関連情報>
- https://www.news.ucsb.edu/2022/020693/energizing-africa
- https://www.sciencedirect.com/science/article/abs/pii/S254243512200304X
南部アフリカの低炭素電力システムを実現するために Enabling a low-carbon electricity system for Southern Africa
A.F.M. Kamal Chowdhury,Ranjit Deshmukh,Grace C.Wu,Anagha Uppal,Ana Mileva,Tiana Curry,Les Armstrong,Stefano Galelli,Kudakwashe Ndhlukula
Joule Published: July 25, 2022
DOI:https://doi.org/10.1016/j.joule.2022.06.030
Highlights
- •We develop cost-optimal electricity pathways for Southern Africa
- •Wind and solar can become the dominant sources of electricity by 2040
- •No new coal capacity is required except when transmission is constrained
- •Nearly half of the planned hydropower capacity is not economical
Context & scale
Electricity demand in the 12 conterminous countries of the Southern African Power Pool (SAPP) is projected to double by 2040. Collectively, they represent about 40% of the total electricity demand in Africa. The challenge is to meet this growing demand while limiting GHG emissions. Current regional electricity plans emphasize the development of new coal, hydropower, and natural gas, despite the rapidly declining costs of wind and solar technologies. Using a detailed electricity planning model that better represents international electricity flows and the variability of wind, solar, and hydropower, we compare all technology and transmission options on more equal footing. Our cost-optimal energy modeling finds that wind- and solar-dominated systems are actually more cost competitive than fossil fuel- or hydro-dominated ones, meeting demand growth without increasing GHG emissions. Also, policy interventions (e.g., clean energy targets or early coal retirements) can reduce emissions at additional costs.
Summary
Southern Africa faces the dual challenge of providing affordable energy to meet rapidly growing electricity demand while limiting carbon emissions and socio-environmental impacts. We combined open-source geospatial, hydrological, and electricity grid-investment models to develop cost-optimal low-carbon electricity pathways for Southern Africa. If technology and fuel prices continue to follow current trends, wind and solar technologies can become the dominant sources of electricity in the region by 2040. Importantly, no new coal capacity is built in any scenario except when inter-regional transmission is constrained. Furthermore, despite the abundant hydropower potential in the region, nearly half of the planned hydropower capacity is not cost competitive, thus supporting freshwater conservation efforts. An 80% clean energy target can halve annual greenhouse gas emissions by 2040, as compared with 2020, with only a modest 6% cost premium. Alternatively, retiring coal plants 20 years earlier could result in even greater emission reductions but could incur 12% higher annual costs.