Low-carbon Energy Research Articles

Techno-economic and environmental assessment of green hydrogen and ammonia production from solar and wind energy in the republic of Djibouti: A geospatial modeling approach

This study conducts a thorough economic and technical analysis to assess the viability of green hydrogen and green ammonia production using renewable energy sources in the Republic of Djibouti. We explore the economic competitiveness of utilizing wind and solar power for sustainable energy production through various measures including levelized cost of energy (LCOE), hydrogen (LCOH), and ammonia (LCOA). Our analysis incorporates sensitivity assessments and Monte Carlo simulations to predict financial feasibility and environmental impact, focusing on CO2 emission reductions. A cost mapping of electricity, green hydrogen, and green ammonia from solar and wind resources was created to find Djibouti's most cost-effective production sites. The feasibility of exporting green ammonia to neighboring countries with high fertilizer demand was also evaluated using rail and truck transport scenarios. Key findings demonstrate that Moulouhlé, endowed with robust wind and solar resources, presents a strategic site for deploying renewable energy technologies. Wind energy, with a lower LCOE of 0.066 $/kWh compared to solar's 0.093 $/kWh, emerges as a more cost-effective solution for both hydrogen and ammonia production. Notably, wind-powered hydrogen production costs are 2.25 $/kgH2, significantly lower than solar-powered costs at 4.17 $/kgH2. In terms of green ammonia, wind power achieves production costs of 399.76 $/tonNH3, outperforming solar power which stands at 537.11 $/tonNH3. Additionally, our study evaluates the logistics of exporting green ammonia, determining rail transport as a more economically viable option than trucking. This research not only underscores Djibouti's potential as a leader in green energy exportation but also aligns with global decarbonization efforts, showcasing significant CO2 savings—154.94 Mt annually from wind. This work emphasizes the importance of strategic resource utilization in Djibouti, offering insights critical for stakeholders in making informed decisions about investing in renewable energy infrastructures. The outcomes suggest a promising future for regional energy sustainability and economic resilience, fostering a transition towards low-carbon energy systems.

The evolution analysis of low-carbon power transition strategies and carbon emission decoupling based on carbon neutrality target

It is necessary for China to accelerate the low-carbon power transition to realize the carbon neutrality target by 2060. Based on the goal of carbon neutrality, Deep Reinforcement Learning with the Double Q-learning method is used to solve a multi-agent game in 30 provinces of China, in an attempt to explore the evolutionary process of regional low-carbon power transition strategies, carbon emissions, and carbon emission decoupling with economic growth. Conclusions are obtained as follows. First, regional low-carbon power transition strategies are not consistent. Though China is bound to achieve the carbon peak and carbon neutrality, the carbon peak and carbon neutrality process will vary widely across regions and over time. Second, the cost of power decarbonization is higher in resource-based regions than that in core regions. The regional coordination policy can reduce the total carbon emissions in resource-based regions, but it will not alleviate their carbon emission decoupling costs. Third, the stable strategy of low-carbon power transition needs faster economic development and more abundant zero-carbon resources. Therefore, the carbon neutrality policy is suggested to be more spatially differentiated, more equitable, and more robust.

Exploring the impact of nanoshaped ceria in the methanol decomposition reaction pathway for clean energy production

The effect of facet exposure in ceria nanostructures on the catalytic properties of Pd/CeO₂ during methanol decomposition was investigated. The results showed the structure sensitive nature of this reaction, with the catalytic activity depending on the facet exposed in the ceria nanostructures. Operando DRIFTS-MS and DFT calculations demonstrated that methanol decomposition proceeds mainly via two reaction pathways depending on the exposed nanofacets: the formate and the formaldehyde pathways. The formaldehyde pathway is inhibited on the (111) nanofacets, where only the formate pathway is energetically favoured, in contrast to the (100) and (110) facets. Superior specific catalytic activity was observed in the catalyst with octahedral morphology, attributed to the higher number of oxygen vacancies per unit surface area, which facilitates the decomposition of formates. By gaining a better understanding of the relationship between the shape control of the catalyst, this work contributes to the collective effort of discovering and implementing sustainable low-carbon energy solutions.

A techno-economic feasibility analysis of solutions to cover the thermal and electrical demands of anaerobic digesters

The use of biogas from anaerobic digestion (AD) has been switching in recent years from electricity to biomethane (BM) production. This choice leads to a higher energy efficiency compared to the use of biogas for combined heat and power (CHP) production, but results in a higher electricity demand for the upgrading and in the necessity of a heat supply for the digesters. This study analyses possible technical solutions, such as heat pumps or wood chip boilers to cover the thermal needs of the digester and photovoltaic panels (PV) to supply electricity. Three feedstocks were considered with high (organic waste), low (livestock manure), and intermediate (sewage sludge) biochemical methane potential (BMP), resulting in different electricity and heating needs. Results show that heat pumps (HP) are an economically viable solution for medium/low BMP feedstocks, for which relative payback times are in the range 1.5–5.4 years; in these cases, a reduction of 47–83 % of greenhouse gases (GHG) emissions and of 59–68 % of non-renewable primary energy is also achieved. For high BMP feedstocks, economic benefits are possible only with low electricity cost (below 130€/MWhel), and a reduction of GHG emissions is possible only using low-carbon electrical energy (below 202 kgCO2eq/kWh).

Experimental Study on Phase Change Energy Storage Flooring for Low-Carbon Energy Systems in Grassland Pastoral

Phase change energy storage technology enhances the integration of renewable resources into low-carbon energy systems for grassland pastoral settlements, further addressing the balance between energy needs and environmental sustainability. This study examines a heating system using an experimental platform in an environmental chamber, where the thermal storage and release processes of phase change energy storage flooring were monitored. The results revealed that phase change energy storage flooring exhibits higher heat transfer efficiency and faster heating rates. Under 40 °C heating conditions, the heating rate of the thermal storage layer increased by 12.5% within 1 h. The flooring also demonstrated superior heat release performance, with the peak heat flux of the thermal storage layer delayed by 15 min. Higher heating temperatures shortened the heating time and extended the heat release duration of the phase change energy storage flooring. Under 45 °C heating conditions, the heat transfer efficiency of the surface temperature of the thermal storage layer increased by 38% within 1 hour and by 24.7% over 4 h. In addition, energy consumption in different tests was analyzed, and thermal conductivity was discussed according to the heat transfer model. Phase change energy storage flooring, when coupled with the abundant solar energy resources available in grassland pastoral areas, presents a viable option for the construction of low-carbon energy systems in grassland pastoral settlements.

Strategic investments and portfolio management in interdependent low-carbon electricity and natural gas markets

Addressing global warming necessitates carbon emissions reduction and renewable energy integration within the energy sector. Gas-Fired Power Plants (GFPP) are appealing to investors due to their low emissions and operational flexibility, which are considered necessary characteristics within low-carbon power systems with increasing renewable energy uncertainty. Investing in GFPPs presents intricate challenges due to the increasingly interdependent electricity and natural gas markets, especially in the light of a low-carbon economy. This work addresses these challenges for a strategic agent by proposing a bi-level optimization framework. The upper-level model derives the optimal electricity portfolio management regarding new investments and strategic biddings, while in the lower-level model, the electricity and gas markets are cleared sequentially under a Carbon Emission Trading Scheme (CETS). Case studies on a Pennsylvania-New Jersey- Maryland (PJM) 5-bus power system and an IEEE 24-bus test system demonstrate the applicability and efficacy of the proposed model in capturing the impact of a transitional integrated market framework on GFPPs investments. Also, introducing stochasticity to the model provides a better insight into the contrasting effects of emission allowance trading and gas prices on investment and bidding strategies.

Bilevel low-carbon coordinated operation of integrated energy systems considering dynamic tiered carbon pricing methodology

The coordinated operation and management of energy and carbon emissions in an integrated energy system (IES) can effectively promote overall energy efficiency and reduce carbon emissions. However, allocating carbon emission responsibilities between transmission-level integrated energy system (TIES) and regional integrated energy system (RIES) is difficult. On the basis of carbon emission flow theory, a model for allocating carbon emission responsibility for IES is developed in this paper. Moreover, the Shapley value method is adopted to obtain the carbon emissions responsibility intervals at the RIES. A dynamic tiered carbon pricing methodology is proposed for the RIES on the basis of equitable carbon emission responsibility intervals. In addition, a bilevel coordinated operation model that imposes carbon price to more fully excavate the low-carbon benefits obtained from operating an IES is proposed. The upper-level model, namely, the TIES, explores the optimal low-carbon schedule for energy networks by imposing fixed carbon price on the energy production costs. The lower-level model, namely, the RIES, investigates the optimal low-carbon energy supply scheme of multienergy coupling equipment and imposes dynamic tiered carbon pricing to adjust the amount of electricity and natural gas consumed. After the whole bilevel model is solved iteratively, equilibrium is reached. Case studies verify the potential and efficacy of the proposed bilevel model, demonstrating superior effectiveness in reducing carbon emissions compared with existing methods.

Low LUMO energy carbon molecular interface to suppress electrolyte decomposition for fast charging natural graphite anode

Graphite holds great potential as a next-generation anode material for energy storage devices. However, the low working voltage of graphite leads to electrolyte decomposition, generating harmful byproducts like HF, while its anisotropic structure results in poor Li+ transport kinetics, making it challenging to balance battery stability and fast-charging performance. Herein, a controllable and scalable carbon molecular layer with low-LUMO (lowest unoccupied molecular orbital)energy is successfully designed to alter charge transfer at the electrode surface. The low LUMO energy carbon molecular interlayer between the graphite and solid electrolyte interphase (SEI) contains numerous strong electron-withdrawing and polar functional groups (C-F and C-N). The functional groups in the interlayer can preferentially and rapidly convert into a LiF and Li3N-rich SEI, attributed to their lower reaction energy barrier compared to electrolyte decomposition. Importantly, the electronic effects and intramolecular synergistic effects between polar functional groups make the conversion of C-F to LiF easier. The interayer superior properties that prevent SEI acid corrosion, accelerates the Li+ desolvation and diffusion in the SEI. Therefore, the graphite anode achieves a balance between fast charging and stability, retaining 64.28 % capacity retention after 1000 cycles at 10 A g−1. Additionally, the graphite anode can be applied in potassium-ion batteries, achieving 148.3 mAh g−1 at 0.2 A g−1. This simple and effective interfacial molecular design offers new insights for simultaneously regulating SEI and suppress electrolyte decomposition.

Technology Progress in High-Frequency Electromagnetic In Situ Thermal Recovery of Heavy Oil and Its Prospects in Low-Carbon Situations

Heavy oil resources are abundant globally, holding immense development potential. However, conventional thermal recovery methods such as steam injection are plagued by high heat loss, substantial carbon emissions, and significant water consumption, making them incompatible with carbon reduction goals and the sustainable socioeconomic development demands. A new method of high-frequency electromagnetic in situ heating, which targets polar molecules, can convert electromagnetic energy into heat so as to achieve rapid volumetric heating of the reservoir. This method has the potential to overcome the drawbacks of traditional techniques. Nevertheless, it faces significant drawbacks such as limited heating range and inadequate energy supply during later production stages, which necessitates auxiliary enhancement measures. Various enhancement measures have been reported, including nitrogen injection, hydrocarbon solvent injection, or the use of nano-metal oxide injections. These methods are hindered by issues such as pure nitrogen being easy to breakthrough, high costs, and metal pollution. Through extensive literature review, this article charts the evolution of high-frequency electromagnetic in situ heating technology for heavy oil and the current understanding of the coupled heat and mass transfer mechanisms underlying this technology. Moreover, based on a profound analysis of the technology’s progression trends, this work introduces a new direction: CO2-N2 co-injection as an enhancement strategy for high-frequency electromagnetic in situ heavy oil recovery. There is promising potential for the development of new technologies in the future that combine high efficiency, low carbon emissions, environmental friendliness, economic viability, and energy conservation. Furthermore, some research prospects in low-carbon situations and challenges for the new technology in future are presented in detail. All in all, the contribution of the paper lies in the summarizing of some main drawbacks of current enhanced electromagnetic in situ thermal recovery methods, and presents a novel research direction of using CO2-N2 co-injection as an enhancement strategy based on its current research status in low-carbon situations.

Winning the transition: Strategic state action in France and Germany amid the low carbon transition and energy shock

European economies are in flux, destabilized by the low carbon transition (LCT) and post-Ukraine energy shock. How are states responding to this instability? This article contributes to emerging environmentally focused Comparative Capitalisms (CC) scholarship by developing a novel framework for analysing how state action is shaped by the demand-competitiveness-energy nexus. We comparatively examine the cases of France and Germany since 2022, drawing upon 19 elite interviews and documentary analysis of stakeholder accounts, to advance three arguments. First, it is essential for CC frameworks to integrate energy supply dynamics to understand state action and processes of capitalist development. Second, the asymmetric impact of the LCT on France and Germany has shaped distinct state-led capitalist restructuring designed to protect and extend national competitive advantages. For Germany, this has primarily involved ‘greening’ its existing export-led model of growth, whereas French state actors are attempting to advance its interests via the ‘strategic autonomy’ (SA) agenda at the domestic and regional levels. Finally, the energy shock has initiated more interventionist state action in Germany that exposes critical instabilities in its export-led growth model. This analysis has significant implications for CC scholarship and its understanding of capitalist development by illustrating the significance of energy supply dynamics and advancing understanding of how disequilibrium can be theorized within the literature.

Review of peer-to-peer energy trading: Advances and challenges

The power system is confronting progress due to the high integration of distributed energy resources (DERs). These DERs are expected to cause challenges for power system operations. Therefore, innovative management approaches were proposed for integrating DERs in future power systems and maximizing DER owners’ benefits, such as peer-to-peer (P2P) energy trading. Direct energy trading between users is made possible by P2P energy trading, which supports bulk power infrastructure operations while supporting local power and energy balance. P2P energy trading is a promising approach to expanding the installation of renewable energy sources and achieving the system flexibility required for the shift to low-carbon energy. The grid is anticipated to gain from P2P energy trading by having lower reserve requirements, peak demand, and network losses. Many studies and pilot projects have shown how P2P energy trading benefits prosumers as well as the grid. However, the widespread use of such trading models remains limited in today's electrical markets. This paper reviews recent advances in the P2P energy system and a perceptive discussion of the challenges that are keeping P2P from becoming a viable energy management solution in the present electrical market. First, the energy network is covered in this paper's description of these new P2P markets; next, the types of P2P energy trading, moving on to the market structure. Then, the technologies and technical approaches behind P2P energy trading are covered. After that, P2P energy trading advances in different systems are discussed. Finally, we identify challenges before making some concluding remarks.

Global value chain participation, globalisation-Energy Nexus and sustainable development in ASEAN

Achieving net zero carbon emissions necessitates a systemic reorganization of global value chains, particularly in the ASEAN region, due to its growing role as a manufacturing hub. This study explores the interaction between global value chains (GVCs), globalization and sustainable development in ASEAN countries from 2014 to 2022. Using data from sources like the World Development Indicators, Human Development Index, Eora Global Value Chain Database, and others, the study employs a system-generalized method of moments to address endogeneity. The findings reveal that GVC participation significantly impacts sustainable development, with a 1 % increase in GVC involvement leading to a 0.11 % rise in sustainable development. Additionally, globalization metrics such as trade openness and merchandise trade, excluding foreign direct investment, also positively influence sustainable development. When combined with GVCs, these factors further enhance sustainable outcomes. The study also highlights the positive impact of trading in low-carbon goods on sustainable development. Based on these findings, the study recommends policies that promote sustainable production practices within GVCs, sustainable urban planning, good governance, and investment in green infrastructure. Additionally, increased investment in renewable energy technologies and infrastructure is essential to ensure equitable access to clean energy. Governments should prioritize transitioning to low-carbon energy sources to mitigate the negative effects of greenhouse gas emissions.

Evaluation of the hydrogen/oxygen and thermoelectric production of a hybrid solar PV/T-electrolyzer system

In order to achieve a sustainable, low-carbon energy future, it is necessary to develop innovative and integrated solutions. However, one of the main obstacles to the advancement of renewable energy is storage. With this in mind, hybrid systems combining solar energy and hydrogen production have great potential. This article focuses on the evaluation of a solar PV/T (photovoltaic-thermal) system coupled with an electrolyser for the joint production of hydrogen and heat. Simulations are performed in MATLAB. The analysis reveals that with PV/T power supply, the production potential is estimated at 179.6 W and 551.9 W respectively for electrical and thermal power. An in-depth study aimed at optimizing the system by evaluating the quality of the energy used in the water electrolysis process makes it possible to analyze the effect of certain operating parameters. With a water flow of 5.7 ×10−3m3/h, a current density of 200 mA/ cm2 and an electrolyzer temperature of 60 °C, the monthly production of hydrogen and oxygen reaches the maximum values of 4.85 m3 and 2.42 m3 respectively. This led to a maximum exergy efficiency of 57.8 %. This study demonstrates the linearity between hydrogen production and current density which at high density reduces exergy performance.

Optimal allocation method of oxygen enriched combustion-carbon capture low-carbon integrated energy system considering uncertainty of carbon-source-load

In the context of green grid, it is crucial to enhance the low-carbon transformation of integrated energy systems. To improve the degree of low-carbon in these systems, this paper proposes an optimal allocation method of oxygen enriched combustion-carbon capture low-carbon integrated energy system considering the uncertainty of carbon-source-load. Firstly, this paper provides an analysis of uncertainties of carbon-source-load and uses budget uncertainty sets to model the three uncertain parameters. Secondly, in the integrated energy system, the by-product O2 of hydrogen production by electrocution and the oxygen storage device are used to provide oxygen-enriched combustion conditions for the gas turbine to reduce the CO2 generated in the combustion process. At the same time, the carbon capture device is used to collect CO2, and the oxygen enriched combustion-carbon capture integrated energy system is formed. Finally, an improved multi-populations quantum-behaved particle swarm optimization algorithm is proposed to solve the proposed model. This method considers the uncertainty of carbon emission intensity, which makes the optimal allocation of integrated energy system more inclined to low-carbon rather than economic. In addition, in terms of model structure, this method integrates oxygen enriched combustion-carbon capture into the integrated energy system to form a low-carbon model, which directly improves the low-carbon performance of the system. The simulation results show that the carbon emission of the proposed method is reduced by 38.8 % compared with other methods.

Retraction Note: How does green digital finance drive the low-carbon energy transition in China?

Retraction Note: How does green digital finance drive the low-carbon energy transition in China?

Analysis of solution strategies for the transition to renewable energy in Saudi Arabia

The shift from fossil fuels to low-carbon energy solutions is crucial to mitigate the effects of climate change. The Kingdom of Saudi Arabia (KSA) has formulated a policy framework to accelerate the development of renewable energy (RE) as part of Vision 2030. Therefore, the transition to RE is vital for reducing dependence on fossil fuels and mitigating climate change. Nevertheless, critical barriers hinder RE adoption in the KSA. This study identified several main barriers, sub-barriers, and solution strategies for the analysis. Therefore, the fuzzy Analytical Hierarchy Process (AHP) method was incorporated to evaluate seven barriers and twenty-eight sub-barriers. Later, the fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method was used to prioritize the nine solution strategies for adopting RE technologies in the KSA. The fuzzy AHP results emphasize that technological, environmental, and market barriers obstruct RE adoption. Fuzzy TOPSIS indicates that public awareness campaigns, energy subsidy reforms, and modernization of the energy grid are the most suitable solutions for the adoption of RE technologies in the KSA. Consequently, this research will help governments, stakeholders, and policymakers expedite RE adoption by determining these barriers and strategies to achieve the Saudi Vision 2030 goal.

Laying the foundations for negative emissions technologies: insights from a workshop

Abstract Pre-empting the worst consequences of climate change requires both mitigation of emissions from the global energy system and carbon dioxide removal through negative emissions technologies. Despite their nascence, negative emissions technologies are being incorporated into nationally determined contributions to achieve ambitious targets. It is therefore urgent to build a scaffolding that enables their expansion. Here, we report results from a workshop that brought together 34 prominent stakeholders, including scientists, engineers, energy system analysts, economists, experts in public policy, and policy makers. Participants discussed the likely cost and performance of these technologies; elucidated the opportunities and risks facing deployment; and envisioned how nations might build the necessary scaffolding for expansion. The majority narrative is that negative emissions technologies will have a bridging role in decarbonizing existing assets. Different models of deployment were proposed. Reaching the scale of deployment necessary to meet emissions targets is lengthy and expensive. Financial and regulatory risks are seen as greater barriers to deployment at scale than technological risk. Greater certainty regarding carbon pricing, production tax credits, and support for geological characterization and trunkline construction could reduce the former. Critical to expansion is a large-scale increase in low-carbon power production; the implementation of regulatory frameworks that remove uncertainty surrounding investment decisions; and prudent societal engagement.

The impact of energy prices in decarbonizing buildings’ energy use in the EU27

The recent surge in end-use energy prices in the EU has intensified the debate on how price signals influence the decarbonization of the building sector, a key contributor to global energy consumption and emissions. This study investigates the role of energy price signals in driving the decarbonization of the EU-27 building sector using the Invert/EE-Lab model to simulate various scenarios up to 2050. The analysis examines the elasticity of energy demand, particularly how different price scenarios impact investment decisions in energy-related technologies. The findings reveal that a 10 % increase in energy prices can lead to a reduction in energy demand by up to 3 %, depending on the scenario. Furthermore, price elasticity varies across different policy and price settings, with stricter regulations resulting in lower elasticity. The results underscore that while stringent regulatory measures can achieve significant energy savings and reduce greenhouse gas emissions, they also limit the responsiveness to price signals, with heat pump shares reaching 47–86 % in high-efficiency scenarios. Conversely, more moderate policy measures increase price elasticity, leading to 15–55 % heat pump shares. This study highlights the importance of better understanding price elasticity in energy modeling to project better the outcomes of policy interventions aimed at achieving a low-carbon energy system.

Empowering energy access: Exploring financial inclusion's impact on energy poverty in the fragile five economies

Energy poverty is a major issue that deepens economic challenges, especially in the five fragile states of Turkey, Brazil, South Africa, India, and Indonesia. The objective of this study is to examine the impact of financial inclusion on energy poverty, as removing financial barriers to energy access and utilisation is critical for sustainable development. The study hypothesizes that financial inclusion plays a decisive role in alleviating energy poverty. The study analyses the second generation panel methods such as AMG, Driscool-Kraay, and FMOLS using annual data from 2000 to 2021 and examines the causal relationships between variables using Dumitrescu-Hurlin panel causality test. The findings reveal that financial inclusion, low carbon technology trade, energy efficiency, economic growth, and human capital play a central role in alleviating energy poverty in these economies. On the other hand, a unidirectional causal relationship was found between financial inclusion and low carbon technology trade, human capital, energy efficiency, and energy poverty. In contrast, a bidirectional causal relationship was observed between economic growth and energy poverty. These findings provide important insights for policymakers and stakeholders; understanding the complex dynamics between financial inclusion and energy poverty can help design targeted strategies to increase energy access and promote inclusive economic development in fragile economies.

Comparative impacts of energy, climate, and economic policy uncertainties on renewable energy

The ongoing adjustment and fluctuation of energy, climate, and economic policies leads to potential policy uncertainty. The potential uncertainty arising from these policies has a wide range of effects on renewable energy technology, leading to changes in investment decisions or consumption patterns. Hence, given the worldwide shift towards sustainable technologies, it is critical to assess how these policy uncertainties will affect renewable power. Given this backdrop, this study delves into the impact of energy policy uncertainty, climate policy uncertainty, economic policy uncertainty, and government effectiveness on renewable energy in the United States. The cross-quantilogram (CQ) methodology is employed by using monthly data from 2002 to 2022. The outcomes reveal that energy policy uncertainty effectively promotes renewable energy in the short run, whereas it serves as a barrier to the adoption of renewables in the long run. Economic policy uncertainty reduces renewable energy consumption in the short run, but it increases in the long run. Moreover, climate policy uncertainty accelerates the transition to low-carbon energy sources. Finally, government effectiveness is a significant supportive element of the energy transition towards renewables.