Global Primary Energy Supply Research Articles

Developing High-Capacity Solid "Molecular Basket" Sorbents for Selective CO2 Capture and Separation.

ConspectusSince carbon-based energy continues to dominate (over 80%) the global primary energy supply, carbon dioxide capture, utilization, and sequestration (CCUS) is deemed to be a promising and viable option to mitigate greenhouse gas emissions and climate change, for which CO2 capture is critical to the overall success of CCUS. Although liquid amine scrubbing is a mature technology for carbon capture, it is energy-intensive and costly due to energy consumption in solvent heating and water evaporation apart from the energy needed to break amine-CO2 bonding. To address this challenge, Song's group developed a new design approach for adsorptive CO2 capture and separation, namely, "molecular basket" sorbents (MBS), without the need for dealing with solvent heating and water evaporation. The solid MBS consisting of polymeric amines (such as PEI) immobilized into nanoporous materials (such as SBA-15) possesses a high capacity for CO2 capture with high selectivity, fast kinetics, and good regenerability. Consequently, MBS can greatly reduce energy consumption and carbon capture cost. Conventional adsorbents such as zeolites, activated carbon, alumina, and silica have low adsorption capacities, and their use of CO2 adsorption requires prior removal of moisture and cooling of flue gas (∼35 °C). On the contrast, the CO2 sorption capacity of MBS can even be promoted by the presence of moisture/steam and reaches the best performance closer to flue gas temperature (∼75 °C). This Account presents an overview of our research progress in the material development and fundamental understanding of MBS for CO2 capture and the separation of CO2 from various gas streams. It begins with an illustration of the MBS concept, followed by efforts to improve the performance and pilot-scale demonstration of MBS for CO2 capture. With the systematic characterization of MBS by various ex situ and in situ techniques, a better understanding is developed for the CO2 sorption process mechanistically. Furthermore, this Account demonstrates how the fundamental understanding of the CO2 sorption mechanism promotes the further development of more robust and advanced sorbent materials with improved CO2 sorption capacity, kinetics of sorption and desorption, and cyclic stability. Finally, an outlook is provided for the future design and development of novel sorbent materials and the CO2 sorption process for various gas streams including flue gas, biogas, air, and hydrogen streams.

Global challenges of electric vehicle charging systems and its future prospects: A review

Global primary energy supply mainly comes from fossil fuels that are limited in supply and have negative impacts on the environment. A large number of conventional vehicles, present on the streets, mainly consume fossil fuels and emit greenhouse gases. The popularity of electric vehicles is increasing rapidly due to various social and economic factors as well as significant environmental impacts. Governments across the world are shifting their sentiments towards electric vehicles (EVs) to reduce these negative effects. Due to this support from governments and public awareness, EVs are increasing rapidly and bringing new types of problems to the existing power system. The rapid increase in charging high-power electric vehicles (EVs) poses challenges to the power system, including load profile distortion, voltage deviation, frequency imbalance, harmonic injection, distribution system component capacity overloading, excess power loss, and grid instability. This study quantitatively analyzes the impact of EV charging on the power system. With an increase in EV penetration from 25% to 50%, the peak power demand on the system rises by 166%. However, implementing a smart charging system optimizes system parameters, leading to reduced power loss, decreased voltage deviation, and a remarkable 96% decrease in the grid's peak power demand compared to conventional uncoordinated charging. Smart charging not only solves existing problems but also facilitates the integration of next-generation technologies like autonomous vehicles, connected mobility, and the energy internet. This research highlights the significant benefits of smart charging in addressing the challenges posed by the rapid growth of EVs while promoting sustainability and technological advancement in the power system.

Approach to local climate zone based energy consumption assessment in an Indian city

Urban areas housing 55% of the global population consume nearly 75% of the global primary energy supply. Rapid population growth and the current pace of urbanization are key challenges to urban sustainability and global energy security. The present study aims to investigate energy consumption patterns for two different building typologies (apartment and office) across major LCZs of Nagpur city using three different approaches (cooling degree days, building energy simulation and indoor operative temperature). It uses micro-meteorological data for two consecutive years as input for building energy simulations. The results show that LCZs exhibited maximum and minimum cooling load during 14:00–16:00 hrs and 06:00–08:00 hrs respectively. For apartment building, district cooling load was reported highest in LCZs 3, 3F and 9 in the range of 1290.23 GJ to 1311.13 GJ while open LCZs and zones with vegetation cover demonstrated lower cooling load. For office buildings, LCZ 9 (11.82%) demonstrated the maximum variation in district cooling load than LCZ 6B. Office buildings require lesser cooling demand than the apartment buildings as they are only used during the daytime. The results provide indispensable information for building energy policymaking in different zones of a city supported by climate based recommendations.

Partial Least Squares Regression of Oil Sands Processing Variables within Discrete Event Simulation Digital Twin

Oil remains a major contributor to global primary energy supply and is, thus, fundamental to the continued functioning of modern society and related industries. Conventional oil and gas reserves are finite and are being depleted at a relatively rapid pace. With alternative fuels and technologies still unable to fill the gap, research and development of unconventional petroleum resources have accelerated markedly in the past 20 years. With some of the largest bitumen deposits in the world, Canada has an active oil mining and refining industry. Bitumen deposits, also called oil sands, are formed in complex geological environments and subject to a host of syn- and post-depositional processes. As a result, some ores are heterogeneous, at both individual reservoir and regional scales, which poses significant problems in terms of extractive processing. Moreover, with increased environmental awareness and enhanced governmental regulations and industry best practices, it is critical for oil sands producers to improve process efficiencies across the spectrum. Discrete event simulation (DES) is a computational paradigm to develop dynamic digital twins, including the interactions of critical variables and processes. In the case of mining systems, the digital twin includes aspects of geological uncertainty. The resulting simulations include alternate operational modes that are characterized by separate operational policies and tactics. The current DES framework has been customized to integrate predictive modelling data, generated via partial least squares (PLS) regression, in order to evaluate system-wide response to geological uncertainty. Sample computations that are based on data from Canada’s oil sands are presented, showing the framework to be a powerful tool to assess and attenuate operational risk factors in the extractive processing of bitumen deposits. Specifically, this work addresses blending control strategies prior to bitumen extraction and provides a pathway to incorporate geological variation into decision-making processes throughout the value chain.

Application of nanofluids for enhanced waste heat recovery: A review

Heat is the most common form of energy either in final or intermediate forms, with the latter enabling energy conversion to other useful forms. Heat is primarily sourced from fossil fuels representing about 80% of the global primary energy supply. However, heat is usually associated with high energy losses as waste heat (WH). Energy conversion losses amount to about 88% of the global energy supply, with about 50% of such losses as WH. Waste heat recovery (WHR) is aiming at recovering such energy losses either as heat, work, or power. Nanofluids (NFs) have been evolved recently as high-performance heat transfer fluids. The use of NFs to improve WHR is very promising in terms of recovery efficiency, potential, and feasibility. For instance, the use of graphene/water NF for WHR from combustion stack gas has resulted in about 25% increase in energy recovery efficiency. Similarly, the use of nanoparticles enhanced phase change material for WHR from steelworks has successfully been used to drive the distillation process increasing the energy capacity of the system by about 2.76 times. The simulations of using Ag/Pentane NF for organic Rankine cycle has increased the overall system efficiency from 11% to 14% at 30% lower exergy destruction and 14% less carbon footprint. This review aims at discussing the application of NFs for improved WHR in different applications. The review discusses first the different WH sources and recovery approaches. Then, the properties and performance of NFs for WHR are thoroughly discussed. The review discusses as well the different thermo-economic and environmental aspects of WHR using NFs. The potential challenges and future aspects associated with the application of NFs for WHR are additionally discussed. Finally, the review provides constructive recommendations and conclusions, shading light on research needs and future perspectives to optimize the performance of such systems. • Different WH sources and recovery approaches are summarized. • The application of NFs for improving WHR is discussed. • Thermo-economic and environmental aspects of WHR using NFs are elaborated. • Future perspectives to optimize the performance NFs in WHR are highlighted.

Renewables‐based decarbonization and relocation of iron and steel making: A case study

AbstractThe article assesses the future role of hydrogen‐based iron and steel making and its potential impact on global material flows, based on a combination of technology assessment, material flow analysis, and microeconomic analysis. Renewable hydrogen‐based iron production can become the least‐cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne. Availability of low‐cost renewable electricity is a precondition. Australia is the world's largest producer of iron ore and at the same time a country with significant low‐cost renewable electricity potential. A shift to direct reduced iron (DRI) exports could reduce global CO2 emissions substantially and at the same time increase value added in Australia, while maintaining steel production in countries that are currently processing ore into iron and steel, such as China, South Korea, and Japan. The approach could be expanded to other parts of the world and other energy‐intensive industry sectors. Such relocation analysis in a climate context can become a new industrial ecology research area. Iron and steel industry CO2 emissions can be reduced by nearly a third, around 0.7 gigatonnes (Gt) CO2 per year. To achieve these emission reductions, investment of USD 0.9 trillion, or 0.7% of the total energy sector investment needs, would be required, global DRI production would have to increase seven‐fold from today's level, and the hydrogen energy used would equal 1% of global primary energy supply. Such a shift could develop from 2025 onward at scale, if the right policies are put in place.

Batch pyrolysis of cotton stalks for evaluation of biochar energy potential

The thermal cracking of cotton stalks (CS) through pyrolysis was undertaken using a laboratory scale batch pyrolysis reactor. The distribution of pyrolysis products were studied dependent on the final pyrolysis temperature which ranged from 300 to 800 °C by 100K intervals. The maximum biochar yield of 46.5% was obtained at 400 °C. As the pyrolysis process temperature increased, the solid char product yield decreased. The largest higher heating value (25.845 MJ kg−1) was obtained at 600 °C. All biochar samples produced between 500 and 700 °C had an energy densification ratio of 1.41, indicating a higher mass-energy density than the initial feedstock. A larger share of syngas and bio-oil were produced at higher temperatures, as estimated. Preferential selection of a char based on the energy yield would lead to a selection of the 400 °C product, while selection based on the energy densification ratio would be for a product obtained between 500 and 700 °C. An energy simulation was conducted which determined that the process is self-sustaining at and above 400 °C. Furthermore, the global energy potential was determined from CS pyrolysis, which was estimated at 380 PJ yr−1 could contribute to roughly 0.1% of the actual global total primary energy supply of 576 EJ yr−1.

Electricity consumption patterns within cities: application of a data-driven settlement characterization method

ABSTRACTUrban areas presently consume around 75% of global primary energy supply, which is expected to significantly increase in the future due to urban growth. Having sustainable, universal energy access is a pressing challenge for most parts of the globe. Understanding urban energy consumption patterns may help to address the challenges to urban sustainability and energy security. However, urban energy analyses are severely limited by the lack of urban energy data. Such datasets are virtually non-existent for the developing countries. As per current projections, most of the new urban growth is bound to occur in these data-starved regions. Hence, there is an urgent need of research methods for monitoring and quantifying urban energy utilization patterns. Here, we apply a data-driven approach to characterize urban settlements based on their formality, which is then used to assess intra-urban urban energy consumption in Johannesburg, South Africa; Sana’a, Yemen; and Ndola, Zambia. Electricity is the fastest growing energy fuel. By analyzing the relationship between the settlement types and the corresponding nighttime light emission, a proxy of electricity consumption, we assess the differential electricity consumption patterns. Our study presents a simple and scalable solution to fill the present data void to understand intra-city electricity consumption patterns.

Delaying future sea-level rise by storing water in Antarctica

Abstract. Even if greenhouse gas emissions were stopped today, sea level would continue to rise for centuries, with the long-term sea-level commitment of a 2 °C warmer world significantly exceeding 2 m. In view of the potential implications for coastal populations and ecosystems worldwide, we investigate, from an ice-dynamic perspective, the possibility of delaying sea-level rise by pumping ocean water onto the surface of the Antarctic ice sheet. We find that due to wave propagation ice is discharged much faster back into the ocean than would be expected from a pure advection with surface velocities. The delay time depends strongly on the distance from the coastline at which the additional mass is placed and less strongly on the rate of sea-level rise that is mitigated. A millennium-scale storage of at least 80 % of the additional ice requires placing it at a distance of at least 700 km from the coastline. The pumping energy required to elevate the potential energy of ocean water to mitigate the currently observed 3 mm yr−1 will exceed 7 % of the current global primary energy supply. At the same time, the approach offers a comprehensive protection for entire coastlines particularly including regions that cannot be protected by dikes.

Bioenergy and climate change mitigation: an assessment

AbstractBioenergy deployment offers significant potential for climate change mitigation, but also carries considerable risks. In this review, we bring together perspectives of various communities involved in the research and regulation of bioenergy deployment in the context of climate change mitigation: Land‐use and energy experts, land‐use and integrated assessment modelers, human geographers, ecosystem researchers, climate scientists and two different strands of life‐cycle assessment experts. We summarize technological options, outline the state‐of‐the‐art knowledge on various climate effects, provide an update on estimates of technical resource potential and comprehensively identify sustainability effects. Cellulosic feedstocks, increased end‐use efficiency, improved land carbon‐stock management and residue use, and, when fully developed, BECCS appear as the most promising options, depending on development costs, implementation, learning, and risk management. Combined heat and power, efficient biomass cookstoves and small‐scale power generation for rural areas can help to promote energy access and sustainable development, along with reduced emissions. We estimate the sustainable technical potential as up to 100 EJ: high agreement; 100–300 EJ: medium agreement; above 300 EJ: low agreement. Stabilization scenarios indicate that bioenergy may supply from 10 to 245 EJ yr−1 to global primary energy supply by 2050. Models indicate that, if technological and governance preconditions are met, large‐scale deployment (>200 EJ), together with BECCS, could help to keep global warming below 2° degrees of preindustrial levels; but such high deployment of land‐intensive bioenergy feedstocks could also lead to detrimental climate effects, negatively impact ecosystems, biodiversity and livelihoods. The integration of bioenergy systems into agriculture and forest landscapes can improve land and water use efficiency and help address concerns about environmental impacts. We conclude that the high variability in pathways, uncertainties in technological development and ambiguity in political decision render forecasts on deployment levels and climate effects very difficult. However, uncertainty about projections should not preclude pursuing beneficial bioenergy options.

Design, Manufacturing and Performance Evaluation of House Hold Gasifier Stove: A Case Study of Ethiopia

Biomass energy accounts for about 11% of the global primary energy supply, and it is estimated that about 2 billion people worldwide depend on biomass for their energy needs. Yet, most of the use of biomass is in an inefficient manner, primarily in developing countries, leading to a host of adverse implications on human health, environment, workplace conditions, and social wellbeing. Therefore, the utilization of biomass in a clean and efficient manner to deliver modern energy services to the world's poor remains an imperative for the development of community. One possible approach to do this is through the use of efficient biomass gasifiers. Although significant efforts have been directed towards developing and deploying biomass gasifiers in many countries, in Ethiopia especially the gasifiers have technical and economic barriers that hinder house hold gasifier dissemination and application. House hold gasifier stove design, manufacture and scaling up their dissemination remains an elusive goal. This article focuses on identification and evaluation of technical and economical limitations of house hold biomass gasifier stoves manufactured and distributed in Ethiopia. Then designing a family size standard gasifier stove and manufacture and evaluate the performance efficiency of the newly designed house hold gasifier stove. Finally device a mechanism that can improve the overall efficiency and applicability of house hold sized gasifier stoves.

Large‐scale bioenergy from additional harvest of forest biomass is neither sustainable nor greenhouse gas neutral

AbstractOwing to the peculiarities of forest net primary production humans would appropriate ca. 60% of the global increment of woody biomass if forest biomass were to produce 20% of current global primary energy supply. We argue that such an increase in biomass harvest would result in younger forests, lower biomass pools, depleted soil nutrient stocks and a loss of other ecosystem functions. The proposed strategy is likely to miss its main objective, i.e. to reduce greenhouse gas (GHG) emissions, because it would result in a reduction of biomass pools that may take decades to centuries to be paid back by fossil fuel substitution, if paid back at all. Eventually, depleted soil fertility will make the production unsustainable and require fertilization, which in turn increases GHG emissions due to N2O emissions. Hence, large‐scale production of bioenergy from forest biomass is neither sustainable nor GHG neutral.

The Physical Economy of the United States of America

The United States is not only the world's largest economy, but it is also one of the world's largest consumers of natural resources. The country, which is inhabited by some 5% of the world's population, uses roughly one-fifth of the global primary energy supply and 15% of all extracted materials. This article explores long-term trends and patterns of material use in the United States. Based on a material flow account (MFA) that is fully consistent with current standards of economy-wide MFAs and covers domestic extraction, imports, and exports of materials for a 135-year period, we investigated the evolution of the U.S. industrial metabolism. This process was characterized by an 18-fold increase in material consumption, a multiplication of material use per capita, and a shift from renewable biomass toward mineral and fossil resources. In spite of considerable improvements in material intensity, no dematerialization has happened so far; in contrast to other high-income countries, material use has not stabilized since the 1970s, but has continued to grow. This article compares patterns and trends of material use in the United States with those in Japan and the United Kingdom and discusses the factors underlying the disproportionately high level of U.S. per capita resource consumption.

The fossil energy/climate change crunch: Can we pin our hopes on new energy technologies?

There is a growing perception by society of the risks of dramatic global climate changes due to anthropogenic greenhouse gases, in particular energy related emissions of CO 2 . This has spurred a renewed interest in carbon free or carbon neutral technologies for converting sources of renewable primary energy to electricity and to transportation fuels. However, it takes energy to produce energy, even when the primary source is energetically cost free, such as solar or wind. The aim of this letter is to present a model which allows the simulation of the energy costs of the deployment of a new energy technology. We show that the new technology may actually be an energy sink, instead of an energy source, relative to the global total primary energy supply (TPES) for many years or decades, depending on its intrinsic energy costs and deployment path, even though stated aims for its gross energy output are achieved. As expected, the energy payback time of the conversion devices, as well as fuel and maintenance costs are critical parameters. We illustrate the general model with simulations of the deployment of photovoltaic electricity, at global and national levels.

Fats and oils as renewable feedstock for chemistry

Agenda 21, the comprehensive plan of action for a sustainable development in the 21 century which was adopted by more than 180 governments in Rio de Janeiro in 1992, is encouraging the environmentally sound and sustainable use of renewable natural resources, interestingly in chapter 4 “Changing consumption patterns”[1]. It was estimated that about 120 billion tons carbon in biomass, equivalent to .80 billion tons of oil equivalents (toe), are generated globally year by year by photosynthesis [2]. About 5% are presently used by man. The global primary energy supply was in 2004 11.2 billion toe and was estimated to be in 2030 20.6 billion toe [3]. Obviously, there seems to be plenty of biomass available, continually generated by photosynthesis year after year. Moreover, mankind has been degrading, in historical times, some billion hectares of areas originally forested and covered with vegetation. Reforestation of these degraded areas is the greatest challenge on the way to a sustainable development. Neglect of reforestation implies that desertification will further progress, transforming more and more of the areas prone to desertification into new deserts [4]. Thus, there is enough land available for the production of biomass to be used as renewable feedstock. Chemists have much to contribute to meet this challenge [5, 6]. From a chemical point of view, about 75% of biomass is carbohydrates, 20% lignins and only about 5% fats and others. Obviously, the detailed knowledge of the chemistry of these biomolecules will be absolutely necessary on the way to a sustainable usage of biomass as renewable feedstock. At present, the feedstocks of the chemical industry are predominantly depleting fossil feedstocks – oil and natural gas – and only a small percentage are renewables, in Germany about 12%. Thus, the chemical industry will have to change its consumption pattern. The German Chemical Society stated in 2002, on the occasion of the World summit on sustainable development in Johannesburg: “Most products obtainable from renewable raw materials may at present not be able to compete with the products of the petrochemical industry, but this will change as oil becomes scarcer and oil prices rise” [7]. This is currently going on. Some examples of this breathtaking process will be discussed in this paper focused on polyols and middleand long-chain dicarboxylic acids. Moreover, the importance of cultivating new oil plants for chemical usage of the oil will be discussed shortly.

Applying bottom-up analysis to identify the system boundaries of non-energy use data in international energy statistics

Data on the non-energy use of fossil fuels in energy statistics are subject to major uncertainties. We apply a simple bottom-up methodology to recalculate non-energy use for the entire world and for the 50 countries with the highest consumption of fossil fuels for non-energy purposes. We quantify worldwide non-energy use in the year 2000 to be 24±2 exajoules (EJ), thereby accounting for 6% of the global total primary energy supply (TPES). Our bottom-up estimates are in line with data from international energy statistics for the entire world and for 14 individual countries. Our estimates exceed official non-energy use data for 22 countries, whereas they are lower than official data in the case of 14 countries. Inconsistent system boundaries of non-energy use data in international energy statistics can explain parts of the observed deviations. We regard our bottom-up methodology as reliable albeit being attached with uncertainties. We recommend its use for energy statisticians and greenhouse gas (GHG) inventory makers to generate a shortlist of countries, for which efforts should be made to clarify and improve the quality of non-energy use data in national and international energy statistics.

Scaling up biomass gasifier use: an application-specific approach

Biomass energy accounts for about 11% of the global primary energy supply, and it is estimated that about 2 billion people worldwide depend on biomass for their energy needs. Yet, most of the use of biomass is in a primitive and inefficient manner, primarily in developing countries, leading to a host of adverse implications on human health, environment, workplace conditions, and social well being. Therefore, the utilization of biomass in a clean and efficient manner to deliver modern energy services to the world's poor remains an imperative for the development community. One possible approach to do this is through the use of biomass gasifiers. Although significant efforts have been directed towards developing and deploying biomass gasifiers in many countries, scaling up their dissemination remains an elusive goal. Based on an examination of biomass gasifier development, demonstration, and deployment efforts in India—a country with more than two decades of experiences in biomass gasifier development and dissemination, this article identifies a number of barriers that have hindered widespread deployment of biomass gasifier-based energy systems. It also suggests a possible approach for moving forward, which involves a focus on specific application areas that satisfy a set of criteria that are critical to deployment of biomass gasifiers, and then tailoring the scaling up strategy to the characteristics of the user groups for that application. Our technical, financial, economic and institutional analysis suggests an initial focus on four categories of applications—small and medium enterprises, the informal sector, biomass-processing industries, and some rural areas—may be particularly feasible and fruitful.

Bioenergy — a renewable carbon sink

Bioenergy is a mature technology which, in its several facets using modern biomass conversion systems, provides a significantly greater contribution towards the global primary energy supply than do all the existing and planned wind and solar projects together. Where specialist long rotation energy crops are grown on land that was previously in pasture or annual crops, biomass also provides a carbon sink. However, the “image” of biomass is generally much poorer than wind and solar in the public mind due to a lack of understanding of the technology. Policy makers and the media also pay greater attention to usually more photogenic wind and solar technologies. This paper presents an outline of the potential energy contribution from biomass with particular emphasis on examples of commercial projects in Australasia.

Dynamics of energy technologies and global change

Technological choices largely determine the long-term characteristics of industrial society, including impacts on the natural environment. However, the treatment of technology in existing models that are used to project economic and environmental futures remains highly stylized. Based on work over two decades at IIASA, we present a useful typology for technology analysis and discuss methods that can be used to analyze the impact of technological changes on the global environment, especially global warming. Our focus is energy technologies, the main source of many atmospheric environmental problems. We show that much improved treatment of technology is possible with a combination of historical analysis and new modeling techniques. In the historical record, we identify characteristic “learning rates” that allow simple quantified characterization of the improvement in cost and performance due to cumulative experience and investments. We also identify patterns, processes and timescales that typify the diffusion of new technologies in competitive markets. Technologies that are long-lived and are components of interlocking networks typically require the longest time to diffuse and co-evolve with other technologies in the network; such network effects yield high barriers to entry even for superior competitors. These simple observations allow three improvements to modeling of technological change and its consequences for global environmental change. One is that the replacement of long-lived infrastructures over time has also replaced the fuels that power the economy to yield progressively more energy per unit of carbon pollution – from coal to oil to gas. Such replacement has “decarbonized” the global primary energy supply 0.3% per year. In contrast, most baseline projections for emissions of carbon, the chief cause of global warming, ignore this robust historical trend and show little or no decarbonization. A second improvement is that by incorporating learning curves and uncertainty into micro scale models it is possible to endogenously generate patterns of technological choice that mirror the real world. Those include S-shaped diffusion patterns and timescales of technological dynamics that are consistent with historical experience; they also include endogenous generation of “surprises” such as the appearance of radically new technologies. Third, it is possible to include learning phenomena stylistically in macro-scale models; we show that doing so can yield projections with lessened environmental impacts without necessarily incurring negative effect on the economy. Arriving on that path by the year 2100 depends on intervening actions, such as incentives to promote greater diversity in technology and lower barriers to entry for new infrastructures that could accelerate historical trends of decarbonization.