CDR deployment
Understanding the complex interaction between CDR pathways and the global electric power system requires examining the roles and contributions of various CDR approaches in achieving climate mitigation goals. Figure 1a illustrates the development and distribution of CDR methods across different modeled scenarios. LUC plays a significant role, especially in the LOW scenario, which relies solely on LUC for negative emissions until the last decade (2040–2050) when DACCS emerges. In scenarios with a broader portfolio of novel CDR approaches, such as the HIGH scenario, the contribution of LUC diminishes considerably by 2050, replaced by BECCS and DACCS as these technologies become more mature and cost-effective 38. Although DACCS deployment is relatively delayed, it becomes a principal CDR approach under the 1.5°C pathway, with gross removals reaching 3 to 3.3 GtCO2/yr by 2050 in the MODERATE and HIGH scenarios, respectively. The 2°C pathway's less stringent requirements may allow for a further delay in DACCS deployment, likely towards the end of the century, providing time for technological advancements and cost reductions. Due to cost-effectiveness, the modeling assumes that high-temperature electric heating DACCS systems are deployed at a much lower scale compared to natural gas-based systems across all scenarios. Despite the limited deployment of the fully electric system, its energy-intensive nature poses major implications for electricity demands. BECCS deployment is expected to begin relatively early, around 2030. Under the HIGH scenario for both 1.5°C and 2°C pathways, BECCS would become the predominant source of negative emissions by 2050, delivering 4.6 and 2.9 GtCO2/yr, respectively. The 1.5°C and 2°C pathways show notable differences in BECCS deployment across sectors. In the 1.5°C pathway, BECCS-electricity dominates over BECCS-liquids, reflecting a prioritization of deep decarbonization in the power sector and an emphasis on electrification as a key mitigation strategy. Conversely, the 2°C pathway has a higher share of BECCS-liquids relative to BECCS-electricity, indicating a reduced emphasis on electrification and sector coupling. While BECCS and DACCS are expected to be the most widely deployed forms of novel CDR, enhanced weathering and biochar also play significant roles in providing negative emissions under the HIGH scenario. In the 1.5°C pathway, gross removals from enhanced weathering and biochar could reach 1.8 and 0.5 GtCO2/yr by 2050, respectively.
The regional variations in the distribution and contribution of various CDR approaches are mainly driven by resource availability, domestic climate targets, and policy incentives. Figure 1b shows the percent share of various CDR approaches in each country/region by 2050 under the most ambitious and optimistic CDR scenario (1.5 C_HIGH). Canada, Russia, Eastern Europe, and Southern/Western Africa will continue to rely heavily on LUC by 2050, with minor contributions from novel CDR technologies. The US, Australia/New Zealand, and several parts of South and Central America are expected to lean towards DACCS, while BECCS is anticipated to be the dominant source of negative emissions in several regions across Asia, Europe, and Eastern/Northern Africa. Enhanced weathering will play a major role in contributing to negative emissions in South and Southeast Asia, and biochar deployment will make significant contributions in India, Indonesia, and many parts of Africa due to favorable climatic conditions 30.
Transformations in the global electricity system
Electricity generation
The interactions between CDR pathways and the electricity sector will determine how the scale of CO₂ removal impacts the sector’s composition (in terms of electricity production) and the broader decarbonization effort. While most CDR approaches typically increase electricity demand, BECCS offers a way to remove CO₂ while also contributing to energy supply including electricity. Figure 2a shows the transformation in global electricity supply under varying CDR scenarios for the 1.5℃ and 2℃ climate pathways. With minimal CDR deployment and no BECCS contribution, the LOW scenario requires the highest level of electricity generation, predominantly from renewables and nuclear energy. Under the 1.5℃ pathway, the LOW scenario sees an almost complete phase-out of unabated fossil fuels by 2050, with renewables and nuclear energy increasing nearly seven-fold and substantial deployment of long-duration energy storage, such as hydrogen, for renewable energy balancing. The MODERATE and HIGH scenarios offer greater flexibility in transforming the electricity mix by allowing continued use of fossil fuels, particularly gas (with and without CCS). In these scenarios, BECCS helps share the emissions reduction burden, enabling the electricity system to leverage gas as a 'transition fuel' due to its cost-effectiveness and lower emissions intensity compared to coal and oil 39. Our results indicate a 47%-56% increase in electricity generation from gas (mainly with CCS) by 2050 relative to 2020 under the MODERATE and HIGH scenarios. Electricity generation from BECCS is projected to account for 2%-4% of the total generation in 2050. The integration of BECCS and overall greater CDR deployment could displace generation from nuclear and renewables by 5%-15% compared to the LOW scenario due to cost-effectiveness.
The significant potential role of BECCS in meeting future electricity demands while contributing to negative emissions carries important regional implications. Under the most ambitious climate target and optimistic CDR assumptions, China, the US, and India are projected to lead in electricity generation from BECCS by 2050, with outputs ranging from 1.0 to 2.2 EJ/yr (Fig. 2b). When considering BECCS' proportional contribution to regional electricity generation, India is expected to maintain a significant reliance on this technology, alongside Mexico and some parts of Central and Southern America. In these regions, BECCS is projected to account for 5%-10% of total electricity generation by 2050 (Fig. 2c). This highlights BECCS's potential importance in their decarbonization strategies, driven by factors such as biomass resource availability, existing bioenergy infrastructure, and policy support. However, large-scale BECCS deployment may pose trade-offs and sustainability challenges surrounding issues such as land-use competition, biodiversity impacts, and water resource management for these regions 40–42.
Electricity prices
The rapid energy transition is projected to increase electricity prices due to the higher initial costs of integrating renewable energy sources and the anticipated rise in carbon pricing mechanisms, which make fossil fuel-based energy generation more expensive. Figure 3a shows the impact of various CDR deployment levels on global electricity price changes under 1.5°C and 2°C pathways. Achieving the 1.5°C target with limited CDR necessitates a swifter and more profound decarbonization of the power sector, resulting in higher electricity prices for consumers. The 1.5°C scenarios generally show higher initial price increases compared to 2°C scenarios. The 1.5°C_LOW scenario, which anticipates the most abrupt energy transition, shows the most significant price increase by 2050, diverging sharply from other scenarios. The 1.5°C_HIGH scenario exhibits the most dramatic price changes, starting with a relatively high price increase in 2025 and ending with the most significant price decrease in 2050. This trajectory suggests that aggressive climate mitigation strategies required for the 1.5°C target may incur higher near-term costs. However, the anticipated mid-century deployment of CDR technologies could potentially lead to significant long-term reductions in electricity prices. The electricity supply sector consistently shows higher price increases across all scenarios compared to the demand sectors, particularly in the early years. Among the demand sectors, the building and transport sectors generally exhibit lower price changes compared to the industry sector.
Regional differences in current electricity mixes, resource potential, technological capacities, and transition requirements manifest as divergent regional price impacts, particularly in scenarios pushing the boundaries of rapid change or limited technology availability. Figure 3b shows the percent change in electricity prices by 2050 relative to 2020 across different countries/regions. The 1.5°C_LOW scenario, which requires the most rapid and aggressive shift to renewable energy deployment, sees some of the highest percentage increases in electricity prices. South Africa and India, in particular, experience a 35–45% increase in electricity prices under this scenario, primarily due to the high costs associated with rapidly phasing out their coal-heavy power system. The US alongside several countries in Asia and Europe also face high price increases of 20%-30% under the 1.5℃_LOW scenario. The HIGH scenarios (both 1.5°C and 2°C), with greater CDR availability, help mitigate price shocks across various countries/regions. Canada, the Middle East, and some parts of South America and Africa are expected to witness decreased electricity prices of about 5%-20% under these optimistic scenarios.
Consumption in final energy
On the demand side, the deployment of CDR technologies could significantly impact the electrification of end-use sectors as a mitigation strategy across different climate pathways, as shown in Fig. 4a. The LOW scenario sees the highest level of electrification in the three end-use sectors. Achieving the 1.5°C climate target with limited CDR deployment to offset emissions from the industry and transport sectors necessitates increased electrification in these sectors by about 28% and 16%, respectively, compared to the scenario with full deployment of CDR options. Most CDR approaches such as DACCS will inevitably interact with the electricity system primarily as consumers of energy, highlighting that while these technologies offer potential solutions for mitigating climate change, they also introduce additional energy demands that must be met. As CDR technologies become more widely deployed towards mid-century, electricity consumption for CDR processes is projected to increase considerably, reaching approximately 1–9 EJ by 2050. Under the 1.5°C pathway, electricity consumption for CDR typically increases with higher CDR deployment. However, for the 2°C pathway, the LOW scenario exhibits higher electricity consumption for CDR compared to the MODERATE and HIGH scenarios. This is likely because the 2°C pathway minimizes reliance on energy-intensive approaches like DACCS when other CDR options are available. In the MODERATE scenario, DACCS is projected to contribute minimally to negative emissions, resulting in nearly non-existent electricity consumption for CDR by 2050. In contrast, in the LOW scenario, DACCS remains the only deployable novel CDR technology, making some level of electricity consumption inevitable.
The large-scale deployment of CDR technologies needed to meet climate targets at national and regional levels will significantly impact electricity consumption in various countries and regions. Figure 4b shows the percentage of electricity consumption for CDR in each country/region’s final energy use across modeled scenarios. In scenarios relying heavily on energy-intensive CDR approaches (1.5℃_MODERATE and HIGH), several parts of South America and Australia/New Zealand will see a significant portion (about 10%-20%) of their electricity consumption dedicated to CDR processes. These regions may be well-positioned to utilize their abundant renewable energy resources to support CDR deployment while minimizing additional emissions 43,44. Meanwhile, the 2°C_MODERATE pathway, which assumes minimal overall CDR electricity consumption, sees zero electricity consumption for CDR in several countries across Africa, Europe, and Southern Asia.
Capacity additions and investment costs
To drive down the power sector's emissions towards zero levels by mid-century, any new generation capacity added globally over the coming decades must be dominated by low or zero-carbon technologies. Fossil fuel-based additions, unless fitted with CCS, would create long-lived, emissions-intensive capital stocks incompatible with long-term climate goals 32. Figure 5a shows how varying levels of CDR deployment can influence capacity additions in the global electricity sector under the 1.5°C and 2°C climate targets. In the 1.5°C pathway, the CDR-constrained scenarios (LOW and MODERATE) necessitate continuous capacity expansion throughout the modeled period to offset potential stranded assets and accommodate the inflexibility and higher reserve margins demanded by stringent mitigation efforts. Meanwhile, the HIGH scenario under 1.5℃, along with all CDR scenarios under the 2°C pathway, reaches peak capacity additions between 2036 and 2040. Decarbonizing electricity supply while meeting projected global demand under the LOW scenario requires cumulative capacity additions which are about 5%-10% higher than the MODERATE scenario and 7%-22% above the HIGH scenario. Capacity additions for unabated coal will cease completely after 2035 under LOW and after 2040 under MODERATE and HIGH in the 1.5°C pathway. The deployment of CCS technology for retrofitting existing fossil fuel plants begins steadily after 2025 under all scenarios, reaching a cumulative capacity of 1450–2800 GW by 2050. Wind and solar capacity additions are projected to increase substantially across all scenarios, accounting for 64–66% of total capacity additions over the modeled period. Additions of nuclear capacity will account for 12–15% of the total. Cumulative BECCS capacity under the MODERATE and HIGH scenarios could reach 160–380 GW, offsetting some of the need for renewables and nuclear capacity relative to the BECCS-exclusive LOW scenario.
The transition towards zero or low-carbon power infrastructure hinges not only on technological advancement but also on the ability to mobilize and channel investments at an unprecedented scale. Figure 5b quantifies the capital requirements for deploying new capacity under modeled scenarios. We find that the full deployment of CDR options could reduce cumulative investment costs by up to 10% and 18% compared to the MODERATE and LOW scenarios, respectively. Investment in solar and wind capacity is projected to reach a cumulative of US$ 17–25 trillion by 2050, representing 45–50% of total investment costs. Nuclear and BECCS, being more expensive, will have disproportionately higher shares of investment costs relative to their shares in capacity additions. The HIGH scenario may require up to US$ 1.3 trillion more investments in BECCS compared to the MODERATE scenario.
The regional variations in cumulative capacity additions and related costs under the most ambitious climate target and optimistic CDR assumptions are shown in Fig. 5c and d. China's extensive energy demand and the need to decarbonize its emissions-intensive power sector significantly amplify its future capacity needs. China's cumulative capacity additions for renewables and nuclear will account for approximately 23% of the world’s total. This translates into an investment cost of about US$ 7.5 trillion, roughly equivalent to 42% of the country’s gross domestic product (GDP) in 2022 45. The US, India, and Europe also see substantial investments in renewables and nuclear power, cumulating to US$ 3-3.5 trillion. China leads again in investments in bioenergy and CCS technologies, followed by India, the US, and the Middle East. Driven primarily by its biomass resource availability 46,47, India's projected capacity investments significantly favor BECCS, potentially accounting for approximately 25% of its total investment costs. Meanwhile, the Middle East's sustained reliance on gas and oil, even in the long term, necessitates substantial investments in fossil CCS technologies, projected to account for about 40% of the region’s total capacity investments.
Stranded capacity and costs
Climate policies aimed at deep decarbonization pose a significant risk of rendering high-emission power sector assets, such as fossil fuel-based plants, economically unprofitable or obsolete before the end of their natural operational lifetimes 48,49. The impact of varying levels of CDR deployment on asset stranding in the electric power sector under the 1.5°C and 2°C climate pathways is illustrated in Fig. 6a. Our modeled scenarios project about 1140–2200 GW of existing power plants becoming stranded from 2016 to 2050. Expanding CDR deployment helps mitigate the overall magnitude and pace of the required premature retirements, particularly under the 1.5°C pathway. Specifically, the HIGH scenario reduces stranded asset capacity by up to 15% and 25% compared to the MODERATE and LOW scenarios, respectively. Conventional coal-fired power plants account for approximately 55%-70% of the total stranded capacity across modeled scenarios. In absolute terms, the LOW scenario sees the highest stranding of coal assets with about 40 and 130 GW more capacity stranding relative to the MODERATE and HIGH scenarios under the 1.5°C pathway, respectively. Interestingly, the HIGH scenario projects a larger share of coal in its total stranded capacity compared to the LOW and MODERATE scenarios. This is because the share of gas in total stranded capacity is significantly reduced under the HIGH scenario which enables the continued use gas as a “transition fuel”. In comparison, the LOW and MODERATE scenarios, particularly under 1.5°C, require earlier stranding of all emission-intensive assets including gas-fired plants. The MODERATE and HIGH scenarios foresee earlier stranding of conventional bioenergy assets due to the potential for retrofitting these plants with CCS technology. Transitioning conventional bioenergy plants to BECCS facilities aligns these assets with stringent climate mitigation goals, incentivizing the early stranding of these plants to facilitate their conversion.
The premature retirement of conventional power plants from 2016 to 2050 could result in cumulative stranding costs of about US$3.6 to 6.8 trillion across modeled scenarios. The HIGH scenario project approximately 5%-10% and 17%-20% lower stranding costs than the MODERATE and LOW scenarios, respectively. Notably, the share of stranding costs for coal power plants is disproportionately larger relative to their share of stranded capacity. This could be attributed to the significantly higher capital expenditures associated with coal power plants and their slower depreciation rates, which stem from their longer assumed operational lifespans 50. This observation highlights significant economic challenges associated with the potential phase-out of conventional coal power plants compared to gas and oil in the context of deep decarbonization.
As countries and regions adopt increasingly ambitious climate policies, such as carbon pricing mechanisms, emissions performance standards, or outright phase-out plans, the economic and regulatory environment for emission-intensive power generation could become highly unfavorable. Figure 6b and c illustrate the regional variations in potential stranded assets and associated costs by 2050 under the 1.5°C_HIGH scenario. China faces the highest levels of prematurely retired assets globally, driven by the need to decarbonize its coal-heavy power sector. China's projected premature retirements reach a cumulative total of 480 GW by 2050, resulting in stranding costs of about US$ 1.9 trillion. Existing coal assets account for 98% of the total stranded capacity, equivalent to approximately 40% of the country’s current coal capacity 51. The US and India rank as the second and third countries most at risk for stranded assets, respectively with nearly identical cumulative stranded capacity. However, India's stranding costs are about 35% higher than those of the US. This discrepancy arises from the differing composition of their stranded assets: in India, about 95% of the total stranded capacity is due to coal assets, whereas in the US, coal accounts for only 55% of the total stranded capacity. Since coal has much higher associated stranding costs compared to gas and oil, India's total stranding costs are substantially greater than those of the US, despite the US having a slightly higher overall stranded capacity. Other countries, such as South Africa and Indonesia, would also experience high potential stranding costs due to their coal-heavy power sectors. In contrast, Russia and the Middle East would see disproportionately lower stranding costs, primarily from gas and oil assets.
Committed emissions
The continued operation of fossil fuel-based power plants over their typical lifetimes would result in a substantial amount of committed emissions 52, posing challenges to both near- and long-term climate goals. By accounting for the expected lifetimes and utilization rates of existing fossil fuel-based power plants, we estimate future "locked-in" emissions if these assets operate as intended (REFERENCE/REF), comparing them with modeled emissions under various CDR deployment scenarios consistent with the 1.5°C and 2°C climate pathways. Figure 7a shows that the continued operation of existing power plants over their full remaining lifetimes would result in approximately 495 GtCO2 in the coming decades, with about 75% of these emissions attributed to coal assets. For a 50% likelihood of limiting global warming to 2°C 53,54, these committed emissions would consume approximately 43% of the remaining carbon budget and nearly exhaust the budget for the 1.5°C-consistent scenario. The premature retirement or retrofitting of existing infrastructure before the end of its expected lifetime could mitigate committed emissions linked to these assets and help align the power sector with decarbonization targets. Our modeled results indicate that the 1.5°C and 2°C pathways require up to 55% and 40% reductions in committed emissions, respectively relative to the REF scenario.
The prospect of large-scale CDR deployment by mid-century could potentially offset committed emissions from existing long-lived assets, reducing the immediate pressure for aggressive premature retirements to meet climate targets. Consequently, scenarios with multi-gigatonnes expectations of CDR enable longer operational lifetimes for emissions-intensive assets, resulting in higher committed emissions compared to scenarios with limited CDR deployment. Under our modeled 2°C pathway, the LOW scenario requires reducing committed emissions by 8% and 12% relative to the MODERATE and HIGH scenarios, respectively. For the 1.5°C pathway, mitigation efforts with LOW CDR deployment necessitate reducing committed emissions by 5% and 15% compared to the MODERATE and HIGH scenarios, respectively. Across all modeled scenarios, the majority of potential emissions reductions are projected to come from the premature retirements of coal assets, with reductions of 35–55% compared to the REF scenario. This is attributable to the high emissions intensity of coal compared to natural gas and oil, as well as the significant share of coal in the existing global power generation mix.
Figure 7b illustrates the committed emissions estimated for various countries/regions under REF compared to the modeled scenarios. China leads in committed emissions from operational power plants at 216 GtCO2, accounting for approximately 40% of the global total. Given that about 97% of China's commitments originate from coal, achieving climate goals will require reductions of approximately 60–100 GtCO2 through extensive stranding of coal assets. The US, Europe, and India collectively account for one-third of global committed emissions. Despite India having the lowest committed emissions among these three regions, it requires the most significant reductions across modeled scenarios, particularly under the most ambitious 1.5°C_LOW scenario. India's higher proportion of emissions from coal generators, combined with its limited potential for CDR deployment under the LOW (no BECCS) scenario, necessitates an aggressive approach to stranding existing assets to meet stringent mitigation targets. The Middle East, Africa, and Latin America and the Caribbean (LAC) contribute the least to global committed emissions. In the Middle East and LAC, natural gas predominates, accounting for roughly one-quarter of global committed emissions from gas-fired generators. Our modeled projections for the Middle East suggest the most modest reductions in committed emissions across all regions, likely due to its minimal reliance on coal-fired power generation and the associated committed emissions.