Search Results (104)

This study proposes the SMR Smart Net-Zero City (SSNC) framework—a scalable model for achieving carbon neutrality by integrating Small Modular Reactors (SMRs), renewable energy sources, and sector coupling within a microgrid architecture. As deploying renewables alone would require economically and technically impractical energy storage systems, SMRs provide a reliable and flexible baseload power source. Sector coupling systems—such as hydrogen production and heat generation—enhance grid stability by absorbing surplus energy and supporting the decarbonization of non-electric sectors. The core contribution of this study lies in its real-time data emulation framework, which overcomes a critical limitation in the current energy landscape: the absence of operational data for future technologies such as SMRs and their coupled hydrogen production systems. As these technologies are still in the pre-commercial stage, direct physical integration and validation are not yet feasible. To address this, the researchers leveraged real-time data from an existing commercial microgrid, specifically focusing on the import of grid electricity during energy shortfalls and export during solar surpluses. These patterns were repurposed to simulate the real-time operational behavior of future SMRs (ProxySMR) and sector coupling loads. This physically grounded simulation approach enables high-fidelity approximation of unavailable technologies and introduces a novel methodology to characterize their dynamic response within operational contexts. A key element of the SSNC control logic is a day–night strategy: maximum SMR output and minimal hydrogen production at night, and minimal SMR output with maximum hydrogen production during the day—balancing supply and demand while maintaining high SMR utilization for economic efficiency. The SSNC testbed was validated through a seven-day continuous operation in Busan, demonstrating stable performance and approximately 75% SMR utilization, thereby supporting the feasibility of this proxy-based method. Importantly, to the best of our knowledge, this study represents the first publicly reported attempt to emulate the real-time dynamics of a net-zero city concept based on not-yet-commercial SMRs and sector coupling systems using live operational data. This simulation-based framework offers a forward-looking, data-driven pathway to inform the development and control of next-generation carbon-neutral energy systems. Full article

This paper analyzes the availability of lithium resources required to support a global decarbonized energy system featuring electrical energy storage based on lithium iron phosphate (LFP) batteries. A net-zero carbon grid consisting of existing nuclear and hydro capacity, with the balance being a 50/50 mix of wind and solar power generation, is assumed to satisfy projected world electrical demand in 2050, incorporating the electrification of transportation. The battery electrical storage capacity needed to support this grid is estimated and translated into the required number of nominal 10 MWh LFP storage plants similar to the ones currently in operation. The total lithium required for the global storage system is determined from the number of nominal plants and the inventory of lithium in each plant. The energy required to refine this amount of lithium is accounted for in the estimation of the total lithium requirement. Comparison of the estimated lithium requirements with known global lithium resources indicates that a global storage system consisting only of LFP plants would require only around 12.3% of currently known lithium reserves in a high-economic-growth scenario. The overall cost for a global LFP-based grid-scale energy storage system is estimated to be approximately USD 17 trillion. Full article

This study aims to develop an optimal underwriting strategy for affordable (H1 and M1) and premium (L1 and M2) electric vehicles (EVs), balancing financial risk and sustainability commitments. The research is motivated by regulatory pressures, risk management needs, and sustainability goals, necessitating an adaptation of traditional underwriting models. The study employs a modified Delphi method with industry experts to identify key risk factors, including accident risk, repair costs, battery safety, driver behavior, and PCAF carbon impact. A sensitivity analysis was conducted to examine premium adjustments under different risk scenarios, categorizing EVs into four risk segments: Low-Risk, Low-Carbon (L1); Medium-Risk, Low-Carbon (M1); Medium-Risk, High-Carbon (M2); and High-Risk, High-Carbon (H1). Findings indicate that premium EVs (L1 and M2) exhibit lower volatility in underwriting costs, benefiting from advanced safety features, lower accident rates, and reduced carbon attribution penalties. Conversely, budget EVs (H1 and M1) experience higher premium fluctuations due to greater accident risks, costly repairs, and higher carbon costs under PCAF implementation. The worst-case scenario showed a 14.5% premium increase, while the best-case scenario led to a 10.5% premium reduction. The study recommends prioritizing premium EVs for insurance coverage due to their lower underwriting risks and carbon efficiency. For budget EVs, insurers should implement selective underwriting based on safety features, driver risk profiling, and energy efficiency. Additionally, incentive-based pricing such as telematics discounts, green repair incentives, and low-carbon charging rewards can mitigate financial risks and align with net-zero insurance commitments. This research provides a structured framework for insurers to optimize EV underwriting while ensuring long-term profitability and regulatory compliance. Full article

The global transition to clean energy necessitates integrated solutions that ensure both environmental sustainability and energy security. This paper proposes a scenario-based modeling framework for urban hybrid energy systems combining small modular reactors (SMRs), photovoltaic (PV) generation, and battery storage within a smart grid architecture. SMRs offer compact, low-carbon, and reliable baseload power suitable for urban environments, while PV and storage enhance system flexibility and renewable integration. Six energy mix scenarios are evaluated using a lifecycle-based cost model that incorporates both capital expenditures (CAPEX) and cumulative carbon costs over a 25-year horizon. The modeling results demonstrate that hybrid SMR–renewable systems—particularly those with high nuclear shares—can reduce lifecycle CO₂ emissions by over 90%, while maintaining long-term economic viability under carbon pricing assumptions. Scenario C, which combines 50% SMR, 40% PV, and 10% battery, emerges as a balanced configuration offering deep decarbonization with moderate investment levels. The proposed framework highlights key trade-offs between emissions and capital cost and seeking resilient and scalable pathways to support the global clean energy transition and net-zero commitments. Full article

To address energy shortages and achieve carbon peaking/neutrality, this study develops a distributed renewable-based integrated energy system (IES) for rural active zero-energy buildings (ZEBs). Energy consumption patterns of typical rural houses are analyzed, guiding the design of a resource-tailored IES that balances economy and sustainability. Key equipment capacities are optimized to achieve net-zero/zero energy consumption targets. For typical daily cooling/heating/power loads, equipment output is scheduled using a dual-objective optimization model minimizing operating costs and CO₂ emissions. Results demonstrate that: (1) Net-zero-energy IES outperforms separated production (SP) and full electrification systems (FES) in economic-environmental benefits; (2) Zero-energy IES significantly reduces rural building carbon emissions. The proposed system offers substantial practical value for China’s rural energy transition. Full article

The maritime industry faces growing pressure to reduce greenhouse gas (GHG) emissions, reflected in the progressive adoption of stricter international energy regulations. Wind-Assisted Propulsion Systems (WAPS) offer a promising solution by significantly contributing to decarbonization. This paper presents a versatile simulation and optimization platform that supports the conceptual design of WAPS-equipped vessels and evaluates the viability of such investments. The platform uses a steady-state force equilibrium model to simulate vessel performance along predefined routes under realistic weather conditions, incorporating regulatory frameworks and economic assessments. A multi-objective optimization framework identifies optimal designs across user-defined criteria. To demonstrate its capabilities, the platform is applied to a bulk carrier operating between China and the USA, optimizing for capital expenditure, net present value (NPV), and CO₂ emissions. Results show the platform can effectively balance conflicting objectives, achieving substantial emissions reductions without compromising economic performance. The final optimized design achieved a 12% reduction in CO₂ emissions, a 7% decrease in capital expenditure, and a 6.6 million USD increase in net present value compared to the reference design with sails, demonstrating the platform’s capability to deliver balanced improvements across all objectives. The methodology is adaptable to various ship types, WAPS technologies, and operational profiles, offering a valuable decision-support tool for stakeholders navigating the transition to zero-carbon shipping. Full article

The construction sector presently consumes about 40% of global energy and generates 36% of CO₂ emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding and the insulated structure, address that challenge. First, the paper categorises VFs by structural configuration, ventilation strategy and functional control into four principal families: double-skin, rainscreen, hybrid/adaptive and active–passive systems, with further extensions such as BIPV, PCM and green-wall integrations that couple energy generation or storage with envelope performance. Heat-transfer analysis shows that the cavity interrupts conductive paths, promotes buoyancy- or wind-driven convection, and curtails radiative exchange. Key design parameters, including cavity depth, vent-area ratio, airflow velocity and surface emissivity, govern this balance, while hybrid ventilation offers the most excellent peak-load mitigation with modest energy input. A synthesis of simulation and field studies indicates that properly detailed VFs reduce envelope cooling loads by 20–55% across diverse climates and cut winter heating demand by 10–20% when vents are seasonally managed or coupled with heat-recovery devices. These thermal benefits translate into steadier interior surface temperatures, lower radiant asymmetry and fewer drafts, thereby expanding the hours occupants remain within comfort bands without mechanical conditioning. Climate-responsive guidance emerges in tropical and arid regions, favouring highly ventilated, low-absorptance cladding; temperate and continental zones gain from adaptive vents, movable insulation or PCM layers; multi-skin adaptive facades promise balanced year-round savings by re-configuring in real time. Overall, the review demonstrates that VFs constitute a versatile, passive-plus platform for low-carbon buildings, simultaneously enhancing energy efficiency, durability and indoor comfort. Future advances in smart controls, bio-based materials and integrated energy-recovery systems are poised to unlock further performance gains and accelerate the sector’s transition to net-zero. Emerging multifunctional materials such as phase-change composites, nanostructured coatings, and perovskite-integrated systems also show promise in enhancing facade adaptability and energy responsiveness. Full article

Achieving climate neutrality goals is inseparable from the sustainable development of modern cities. Municipal wastewater treatment plants (WWTP) are among the starting points when moving cities to Net-zero Greenhouse Gas (GHG) emissions and climate neutrality. This study focuses on the analysis of the integration of green hydrogen (H₂) and biomethane technologies in WWTPs, and on the impact of this integration on WWTPs’ energy neutrality. This study treats WWTP as an integrated energy system with certain inputs and outputs. Currently, such systems in most cases have a significantly negative energy balance, and, in addition, fossil fuel energy sources are used. Key findings highlight that the integration of green hydrogen production in WWTPs and the efficient utilization of electrolysis by-products can make such energy systems neutral or even positive. This study provides an analysis of the main technical presumptions for the successful integration of green hydrogen and biomethane production processes in WWTP. Furthermore, a case study of a real wastewater treatment plant is presented. Full article

Genotype by environment (G × E) interaction is a magnitude change in the performance of a genotype when grown in contrasting environments. The sensitivity of a genotype to different environmental conditions is an important determinant of its suitability for cultivation in a specific environment or across multiple environments. In many nations of the world, where the drive to achieve a net-zero CO₂ emission by 2030 has spurred significant investments in clean energy sources such as photovoltaics with a resultant conversion of some agricultural lands to photovoltaic facilities, there is a need to find the right balance between addressing the food and energy crises. Agri-photovoltaics (APV) offer a sustainable solution by allowing crops to grow underneath photovoltaic panels. However, selection efficiency and repeatability of APV experimental results could be marred by the presence of G × E interaction. The study objective was to identify mungbean genotype(s) with a high yield potential and broad adaptability across APV environments. Five mungbean (Vigna radiata L.) genotypes, Tvr18, Tvr28, Tvr65, Tvr79, and Tvr 83, were assessed under six contrasting APV environments, EPV-R, EPV-D, NPV-R, NPV-D, WPV-R, and WPV-D, at the Agri-PV Food and Energy Training Center, University of Nigeria, Nsukka. The experiment was a split-plot design, with the environment as the whole-plot factor while genotype was the sub-plot factor with five replications. The additive main effects and multiplicative interaction (AMMI) and the Finlay and Wilkinson joint regression analysis confirmed significant genotype, environment, and G × E interaction effects for mungbean seed yield. Two genotypes, Tvr28 and Tvr83 expressed broad adaptability to the APV environments with higher yields (2.60 and 2.50 t ha⁻¹), ranking first and second, respectively. In contrast, the Tvr79 genotype displayed the highest sensitivity (2.95) to environmental variation and was unstable across the environments with higher IPCA1 and ASV scores of −1.17 and 1.39, respectively. The EPV-R recorded the highest yield (2.61) with low interaction effect (0.38), whereas the WPV-D environment had the least yield (1.71) and was the most unstable (−0.48). Conclusively, the Tvr28 and Tvr83 genotypes and the EPV-R environment were the ideal genotypes and environment, respectively, and are therefore recommended for use in APV facilities. Full article

Achieving net-zero greenhouse gas emissions by 2050 requires CO₂-neutral industrial process heat, with seasonal energy storage (SES) playing a crucial role in balancing supply and demand. This study reviews thermal energy storage (TES) and Power-to-X (P2X) technologies for applications without thermal grids, assessing their feasibility, state of the art, opportunities, and challenges. Underground TES (UTES), such as aquifer and borehole storage, offer 1–26 times lower annual heat storage costs than above-ground tanks. For P2X, hydrogen storage in salt caverns is 80% less expensive than in high-pressure tanks. Methane and methanol storage costs depend on CO₂ sourcing, while Renewable Metal Energy Carriers (ReMECs), such as aluminum and iron, offer high energy density and up to 580 times lower storage volume, with aluminum potentially achieving the lowest Levelized Cost of X Storage (LCOXS) at a rate of 180 EUR/MWh of energy discharged. Underground TES and hydrogen caverns are cost-effective but face spatial/geological constraints. P2X alternatives have established infrastructure but have lower efficiency, whereas ReMECs show promise for large-scale storage. However, economic viability remains a challenge due to very few annual cycles, which require significant reductions of investment cost and annual cost of capital (CAPEX), as well as improvements in overall system efficiency to minimize losses. These findings highlight the trade-offs between cost, space requirements, and the feasibility of SES deployment in industry. Full article

Achieving the Paris Agreement’s 1.5 °C target requires a global-scale energy transition, reaching net-zero emissions by 2050. This transition demands not only a rapid expansion of renewable energy but also significant upfront energy investment, presenting potential trade-offs between near-term energy security and long-term sustainability. Assuming we cannot rely on as yet unproven negative emissions technology, reductions must be achieved directly, requiring fossil fuel phase-out, accelerated electrification, and substantial renewable infrastructure development. This study presents a detailed, transparent methodology for the creation of a simplified global energy system model designed to rapidly evaluate trade-offs between energy and climate policy, integrating energy investment, depletion, and saturation dynamics into energy transition scenarios. The model simulates energy supply and demand across major sectors, accounting for the upfront energy costs of deploying new renewable infrastructure and the dynamics of electrification in different demand sectors. Its transparent, user-controllable framework allows for rapid scenario adjustments based on variables such as population growth, per capita energy demand, rate and extent of electrification, and strength of climate policy. The primary purpose of this paper is to present the system modelling framework. However, we also present preliminary results from scenario analysis that point to two emergent risks: (1) prioritising energy security increases the likelihood of exceeding carbon budgets, while (2) stringent emissions reductions heighten the risk of energy shortages. Even under non-existent climate policy, fossil fuel depletion makes both the renewable transition and electrification of demand inevitable, though delayed transition leads to more severe emissions overshoot. These findings underscore the urgent need for demand reduction strategies and a more nuanced understanding of the energy investment required for decarbonisation. By offering a flexible scenario tool, this study contributes to informed public discourse and policy decisions on balancing energy security, emissions reduction, and climate resilience. Full article

This study examines Türkiye’s compliance with the Paris Agreement by comparing its climate policy framework with those of Germany and Spain—two EU countries with absolute, legally binding emission reduction targets. Despite ratifying the Paris Agreement in 2021 and declaring a net-zero target for 2053, Türkiye’s Nationally Determined Contribution (NDC) lacks absolute reduction commitments and a comprehensive Climate Act. This gap is particularly critical given the EU’s implementation of the Carbon Border Adjustment Mechanism (CBAM), which links climate action to trade competitiveness. Using a comparative policy analysis approach, this study evaluates official emission data, legal documents, and EU climate progress reports to assess the coherence of Türkiye’s climate strategy. The findings indicated that Türkiye’s emissions continue to rise in the presence of fossil fuel domination and the absence of binding targets. Conversely, Germany and Spain have reduced emissions through robust legislation, functioning Emissions Trading Systems, and long-term investment in renewables. This study offers policy recommendations tailored to Türkiye’s context, including the adoption of absolute and binding targets, acceleration of renewable energy—especially solar—and the promotion of community-based energy models, inspired by Spain’s approach. Additionally, mechanisms to balance energy security, local acceptance, and decarbonization are discussed, drawing from Germany’s phased fossil fuel exit. The results indicate that Türkiye’s ability to align with EU climate targets and the Paris Agreement without compromising its development priorities or energy supply security can only be achieved with a realistic roadmap and specific reforms. Full article

The net zero emissions policy represents a crucial component of the global initiative to address climate change. The European Union has set a target of achieving net zero greenhouse gas emissions by 2050. This study assesses Poland’s feasibility of achieving net zero emissions. Currently, Poland relies on fossil fuels for approximately 71% of its electricity generation, with electricity accounting for only approximately 16% of the country’s total final energy consumption. Accordingly, the transition to net zero carbon emissions will necessitate significant modifications to the energy system, particularly in the industrial, transport, and heating sectors. As this is a long-term process, this article demonstrates how the development of renewable energy sources will progressively necessitate the utilisation of electrolysers in line with the ongoing industrial transformation. A new framework for the energy system up to 2060 is presented, with transition phases in 2030, 2040, and 2050. This study demonstrates that it is feasible to attain a sustainable, zero-emission, and stable energy system despite reliance on uncontrolled and weather-dependent energy sources. Preparing the electricity grid to transmit almost three times the current amount represents a significant challenge. The resulting simulation capacities, comprising 64 GW of onshore wind, 33 GW of offshore wind, 136 GW of photovoltaic, 10 GW of nuclear, and 22 GW of electrolysers, enable a positive net energy balance to be achieved under the weather conditions observed between 2015 and 2023. To guarantee system stability, electrolysers must operate within a centralised framework, functioning as centrally controlled dispatchable load units. Full article

The UK net zero strategy aims to fully decarbonize the power system by 2035, anticipating a 40–60% increase in demand due to the growing electrification of the transport and heating sectors over the next thirteen years. This paper provides a detailed technical and economic analysis of the role of energy storage technologies and transmission lines in balancing the power system amidst large shares of intermittent renewable energy generation. The analysis is conducted using the cost-optimizing energy system modelling framework REMix, developed by the German Aerospace Center (DLR). The obtained results of multiple optimization scenarios indicate that achieving the lowest system cost, with a 73% share of electricity generated by renewable energy sources, is feasible only if planning rules in England and Wales are flexible enough to allow the construction of 53 GW of onshore wind capacity. This flexibility would enable the UK to become a net electricity exporter, assuming an electricity trading market with neighbouring countries. Depending on the scenario, 2.4–11.8 TWh of energy storage supplies an average of 11% of the electricity feed-in, with underground hydrogen storage representing more than 80% of that total capacity. In terms of storage converter capacity, the optimal mix ranges from 32 to 34 GW of lithium-ion batteries, 13 to 22 GW of adiabatic compressed air energy storage, 4 to 24 GW of underground hydrogen storage, and 6 GW of pumped hydro. Decarbonizing the UK power system by 2035 is estimated to cost $37–56 billion USD, with energy storage accounting for 38% of the total system cost. Transmission lines supply 10–17% of the total electricity feed-in, demonstrating that, when coupled with energy storage, it is possible to reduce the installed capacity of conventional power plants by increasing the utilization of remote renewable generation assets and avoiding curtailment during peak generation times. Full article

This paper presents a state-of-the-art review of digital transformation for developing smart net-zero cities, highlighting the significance of systems thinking and the key components of digital transformation including people, data, technology and process. Urban areas are experiencing increasing challenges from rapid growth and climate issues, making digital transformation a crucial strategy for enhancing sustainability and efficiency. In this context, systems thinking is essential, as it provides a holistic perspective that acknowledges the interdependence of urban sectors which can facilitate a more comprehensive, adaptable, and strategically integrated approach. This review examines findings from 22 sources and proposes a framework to investigate and represent the necessity of a digital transformation approach that effectively balances these elements and promotes a systems thinking approach. Also, by examining the findings from a systems thinking perspective, this research analyses the potential of effective digital transformation to support the complex needs of smart net-zero city developments. The findings indicate a widespread recognition of the digital transformation potential as a practical implementation strategy. It is imperative to formulate digital transformation strategies that are practical and comprehensively incorporate all elements: people, technology, processes, and data. Additionally, the review highlights the critical role of systems thinking in the development of these digital transformations as it facilitates the integration of interdependent urban sectors, including energy, transformation, and building, to achieve a holistic and integrated transformation. Full article