Emission Energy Research Articles

Active and Durable Platinum Group Metal-Free Electrocatalysts for Hydrogen Evolution Reaction in Alkaline Systems

Net-zero emission energy technologies are urgently needed to mitigate climate change. Generation of “green” hydrogen via low-temperature water electrolysis using renewable electricity and its utilization in fuel cells for power generation when needed is a highly promising path towards achieving zero emission of greenhouse gases [1]. To guarantee the market affordability of low temperature water electrolyzers, cost and performance targets must be met [1]. The need for expensive catalysts based on platinum group metals (PGMs) in proton exchange membrane water electrolyzers (PEMWE) is currently the main obstacle to their widespread deployment. At the same time, liquid alkaline water electrolyzers (LAWE) exhibit the advantage of operation using catalysts based on earth abundant-based elements [2]. The main drawback of LAWE is the use of strongly alkaline and thus corrosive electrolyte (20-40% KOH), which negatively impacts the catalyst durability. The latter limitation comes on top of low current-density operation and losses in the catalyst performance often occurring as a result of current reversal during shut down [3].Ni-based catalysts, e.g., binary Ni-Mo based materials, display the most promising activity in hydrogen evolution reaction (HER) among non-PGM materials [4]. However, their durability is still a major concern [5]. In one approach, tailoring the design and altering the electronic structure of the NiMo catalysts is an effective route to achieve a higher durability [6].In this work, we designed a novel and facile synthesis approach to developing binder-free Ni-Mo- phosphide electrocatalysts (Ni-Mo-P) in two steps. In the first step, Ni and Mo were deposited on a Ni-foam substrate from a solution containing complexes of the two metals. In the second step, the deposit was phosphidated via reactive annealing in a presence of phosphorus precursor. The formation of NiMo-phosphide was confirmed by XRD. The thus-synthetized catalysts were electrochemically characterized in a three-electrode cell set-up, showing a decent HER activity. The durability of the catalyst was then assessed for 100 h in 1 M KOH solution under constant current operation, with no activity loss detected. We will compare performance of our catalysts with that of the commercially available Ni and Ni-Mo HER electrocatalysts.

Zero-Emission Hydrogen Production at on-Site Hydrogen Refueling Station Using Excess Electricity in Kyushu

Introduction In Japan, the shift from CO2-emitting energy sources toward carbon neutrality is proceeding rapidly. Approximately 27% of the electricity generated in Japan is generated using zero CO2 emission energy sources including renewable energy. Especially in Kyushu island, located in the western region of Japan, approximately 58% of electric energy is provided by zero-emission power generation, and energy conversion is steadily progressing toward achieving carbon neutrality by 2050. The introduction of offshore wind power and other renewable energy facilities is planned for the Kyushu region in the future, which is expected to further reduce CO2 emissions in the power generation sector. Meanwhile, energy management issues have become apparent, such as the fact that some electricity generated cannot be used due to reasons such as the imbalance between supply and demand of electricity. In this study, to investigate methods to store and use excess electricity and resolve the imbalance, we aims to clarify the effect of hydrogen production system on imbalance resolution. To evaluate its effect, demonstration studies are currently underway at an on-site hydrogen production type hydrogen station. Research Issues In this demonstration study, an on-site hydrogen station has been installed and demonstrated that can produce hydrogen using a water electrolyzer(Hitachi Zosen Corp.), compress hydrogen using a hydrogen compressor(Hydro-Pac. Inc.), and fill hydrogen using a hydrogen supply unit (TATSUNO Corp.) with a pre-cooling heat exchanger (ORION Machinery Co., Ltd.). Energy management equipment that makes effective use of electric power that cannot be used even if generated and equipment that associates the power required when operating facilities with zero-emission power sources have also been installed. And the realization of carbon neutrality for the entire hydrogen station's power consumption, its component power sources, and excess power usage status are being analyzed and examined in this study. This presentation will report the results and its analysis of the demonstration of hydrogen production by zero-emission power source using the above facilities. Acknowledgement This research was supported by New Energy and Industrial Technology Development Organization (NEDO), project No. JPNP14026.

(Invited) Emissive Charge-Transfer Excited-State between Organic Conjugated Molecule and Two-Dimensional Inorganic Nanosheet

The unique properties of two-dimensional (2D) materials have boosted intensive interests in combining distinct 2D materials into organic-inorganic heteronanostructure interfaces for device and sensor applications. The hetero-interfaces, integrating atomically thin inorganic materials with an unlimited variety of organic molecules, provide an ideal platform for broader, superior, and on-demand functional applications by incorporating customized organic molecules that particularly exhibit excellent optical and optoelectronic properties. Especially, unique electronic and optical properties discovered for mono- or few-layered transition metal dichalcogenides, represented by MoS2, have rendered them as suitable platforms to host organic π-conjugated compounds. As such, there have been investigations on photodynamic processes at interfaces between MoS2 and various π-conjugated compounds.1 However, previously reported hybrid interfaces were constructed by amorphous-deposition or covalent linkage using long, flexible bridges and thus, the inhomogeneous interfacial structures make it difficult to elucidate the relationship between the interface structure and photodynamics.In this study, we designed and synthesized a hetero-nanostructure interface between an organic π-conjugated molecule (pyrene, Py) and 2D inorganic nanosheet (mono- or few-layered MoS2) with a well-defined bridge at a molecular level (Figure 1).2 As the bridge between Py and MoS2 basal plane, we employed N-benzylsuccineimide structure to form Py-Bn-MoS2.Spectroscopic measurements revealed that the locally-excited (LE) state of pyrene in Py-Bn-MoS2 efficiently generates a long-lived charge-transfer (CT) excited state that straddles the interface of pyrene–MoS2 nanosheet. The CT excited-state is highly emissive (0.68) and relaxes to the ground state without forming the complete charge-separated (CS) state. To the best of our knowledge, this is the first observation of unusually intense emission from the CT excited state at well-defined hetero-nanostructure interface of organic π-conjugated molecules and 2D inorganic nanosheets. Theoretical studies elucidated the interaction of MoS2 vacant orbitals with the pyrene LE state to form the CT excited-state showing distinct solvent dependence of the emission energy. These findings provide important implications for manipulating the LE, CT, and CS states at the interface of photoactive organic molecules and inorganic semiconducting nanosheets. References Baek, J.; Umeyama, T.; Choi, W.; Tsutsui, Y.; Yamada, H.; Seki, S.; Imahori, H. Formation and Photodynamic Behavior of Transition Metal Dichalcogenide Nanosheet-Fullerene Inorganic/Organic Nanohybrids on Semiconducting Electrodes. Chem. Eur. J. 2018, 24, 1561−1572.Umeyama, T.; Mizutani, D.; Ikeda, Y.; Osterloh, W. R.; Yamamoto, F.; Kato, K.; Yamakata, A.; Higashi, M.; Urakami, T.; Sato, H.; Imahori, H. Emissive Charge-Transfer Excited-State at Well-Defined Hetero-Nanostructure Interface of Organic Conjugated Molecule and Two-Dimensional Inorganic Nanosheet. Chem. Sci. 2023, 14, 11914−11923. Figure 1

Logarithmic soft theorems and soft spectra

Using universal predictions provided by classical soft theorems, we revisit the energy emission spectrum for gravitational scatterings of compact objects in the low-frequency expansion. We calculate this observable beyond the zero-frequency limit, retaining an exact dependence on the kinematics of the massive objects. This allows us to study independently the ultrarelativistic or massless limit, where we find agreement with the literature, and the small-deflection or post-Minkowskian (PM) limit, where we provide explicit results up to O(G5). These confirm that the high-velocity limit of a given PM order is smoothly connected to the corresponding massless result whenever the latter is analytic in the Newton constant G. We also provide explicit expressions for the waveforms to order ω−1, log ω, ω(log ω)2 in the soft limit, ω → 0, expanded up to sub-subleading PM order, as well as a conjecture for the logarithmic soft terms of the type ωn−1(log ω)n with n ≥ 3.

Alkaline Hydrogen Evolution Reaction Electrocatalysts for Anion Exchange Membrane Water Electrolyzers: Progress and Perspective.

For the aim of achieving the carbon-free energy scenario, green hydrogen (H2) with non-CO2 emission and high energy density is regarded as a potential alternative to traditional fossil fuels. Over the last decades, significant breakthroughs have been realized on the alkaline hydrogen evolution reaction (HER), which is a fundamental advancement and efficient process to generate high-purity H2 in the laboratory. Based on this, the development of the practical industry-oriented anion exchange membrane water electrolyzer (AEMWE) is on the rise, showing competitiveness with the incumbent megawatt-scale H2 production technologies. Still, great challenges lie in exploring the electrocatalysts with remarkable activity and stability for alkaline HER, as well as bridging the gap of performance difference between the three-electrode cell and AEMWE devices. In this perspective, we systematically discuss the in-depth mechanisms for activating alkaline HER electrocatalysts, including electronic modification, defect construction, morphology control, synergistic function, field effect, etc. In addition, the current status of AEMWE is reviewed, and the underlying bottlenecks that impede the application of HER electrocatalysts in AEMWE are summarized. Finally, we share our thoughts regarding the future development directions of electrocatalysts toward both alkaline HER and AEMWE, in the hope of advancing the commercialization of water electrolysis technology for green H2 production.

Aminocarbonyl Fluorophores with a Strong Emissive Inverted Solvatochromism.

Three aminocarbonyls were synthesized, and their emissive spectral behavior recorded at various solvent polarities showed marked inverted solvatofluorochromism. The emission energy inversion occurs at moderate solvent polarities and was found to be triggered by a change in the solute-solvent interaction responsible for the stabilization of the highly zwitterionic excited state of the dyes, from dipolarity to acidity.

Enhanced disinfestation in grain spawn production through cold plasma and sodium hypochlorite synergy

Heat-resistant fungal conidia are a common source of contamination and can cause significant difficulties in producing spawns. Through the use of PCR method, Aspergillus tubingensis and Aspergillus flavus as common microbial contaminants found in wheat grain spawn were identified that had been sterilized at 120 ºc for 2 h. Since these conidia are highly resistant to standard sterilization techniques, alternative methods were used to treat them with NaOCl and cold plasma and evaluate their effectiveness in reducing contamination. Optical emission spectroscopy (OES) analysis of the plasma showed dominant emissions from the N2 second positive system and N2+ first negative system, while reactive oxygen species (ROS) spectral lines were undetected due to collision-induced quenching effects. Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDXS) analyses revealed notable alterations in the elemental makeup of conidia surfaces, as evidenced by a marked rise in levels of Na, O, Cl (in the case of NaOCl treatment) and N (in the case of plasma treatment). The conidia size was reduced at lower levels of NaOCl, but with increased concentrations and plasma treatment, the conidia underwent rupture and, in some cases, pulverization. The research suggests that utilizing a combined approach can be highly effective in eliminating heat-resistant fungal conidia and drastically cutting down the sterilization time for producing wheat spawn to only 30 s.

Optimal control framework for cost-effective, intelligent, renewable energy-driven communities in Norway, enhanced by ANN and grey wolf method

The present work introduces a novel yet smart energy system to decarbonize the energy mix, provide cost-effective green energy, and help to achieve sustainable energy production/storage/usage. Smart hydronic units and multiple controllers are the backbone of this idea, which aims to monitor energy conversion among components, the grid, and users through an innovative rule-based framework. This clever integration results in smaller components, bidirectional grid connection, and increased penetration of renewable energy sources into the local energy network. The system is driven by photovoltaic thermal panels and a biomass heater integrated with a heat pump and internal combustion engine. The TRNSYS-MATLAB framework evaluates the system's practicality from all aspects. Multi-objective optimization based on the grey wolf approach equipped with artificial intelligence is added to find the most optimal state. Compared to the conventional system in Norway (hydropower + wind), the proposed smart integration achieves up to 55 % and 5.4 % reduction in energy costs and emission index. In particular, the carbon emission index is lowered to 36.3 g/kWh, and the energy cost is decreased to 38.4 $/MWh. Also, the parametric analysis indicates a conflictive change among key metrics when altering a variable, necessitating the multi-objective optimization to achieve a balancing trade-off. The optimization reduces the emission index, investment cost, and energy cost by about 1.8 g/kWh (5 %), 156,000 $/year (2.5 %), and 1.5 $/MWh (4 %) while improving the efficiency by about 1.7 % compared to the design condition. The suggested system generates 17,830 MW/year of clean energy and can mitigate carbon dioxide emissions by 552,000 kg per year compared to the Norwegian energy mix.

Energy efficient strategy for heterogeneous truck platooning based on a non-uniform platooning model

To investigate the energy-saving advantages of truck platoons, this study focused on two, three, and six-axle trucks as research subjects. A non-uniform platoon model of trucks was constructed based on braking performance differences. The aerodynamic characteristics of the non-uniform platoon fleet were analyzed in depth using numerical simulation methods, and the fuel consumption rate of the fleet was calculated. In a heterogeneous three-vehicle platoon, the 3-2-6 platooning approach exhibited the most effective reduction in fuel consumption, whereas the 3-6-2 platooning approach was the least effective. For a four-vehicle heterogeneous platoon comprising a three-axle truck, a six-axle truck, and two two-axle trucks, the 3-2-2-6 platooning approach yielded the best fuel efficiency. In a four-vehicle heterogeneous platoon with a two-axle truck, a six-axle truck, and two three-axle trucks, the 3-2-3-6 platooning approach proved to be the most effective in reducing fuel consumption. In a four-vehicle heterogeneous fleet composed of two-axle trucks, three-axle trucks, and two six-axle trucks, the 3-2-6-6 platooning approach achieved the best fuel efficiency. The conclusions of this study offer a fundamental scheme for truck formation, laying a crucial theoretical foundation for energy conservation and emissions reduction in transport systems.

Industry Energy Dependence Characteristics Under Different Energy Consumption Accounting Scopes: A Comparison Between China and the U.S.

Energy plays a vital role in the sustainable development of the economy and society. The key measures for achieving sustainable development include optimizing the energy structure, improving energy efficiency, and reducing reliance on non-renewable energy sources. This study constructs a monetary energy consumption database for China that distinguishes between energy resources used as raw materials and those used as other intermediate inputs, based on China’s annual input–output table from 2001 to 2020. In this paper, the direct energy consumption and energy conservation potential of 33 industries in both China and the United States are compared under the following three energy consumption scopes: not excluding energy used as raw materials, excluding energy used as raw materials for the production of non-energy products, and excluding energy used as raw materials for the production of non-energy products or the production of energy products through non-combustion processes. This study also compares the direct energy dependence characteristics of these industries. The following conclusions are made: First, the energy consumption structure varies greatly under different scopes, of which the third scope is closest to the international standards. Second, China’s raw materials industries have made some progress in energy conservation, and their gap with those in the U.S. has started to narrow. Third, China’s high-tech industries still have potential for energy conservation and emission reduction.

Exploration of the plastic packaging product industry towards green manufacturing, efforts to consolidate environmental impact versus productivity issues

Plastic products, including plastic packaging, were products whose increasing demand continued because the community still needed plastic as packaging. On the other hand, plastic waste, which was increasingly high and difficult to decompose, was a problem that needed to be solved together. This study aims to understand how plastic company packaging implements TQM, its environmental impact, and how plastic packaging companies are taking steps towards green manufacturing. This research used a qualitative phenomenological method to understand the problem based on the actor’s perspective. The data collection method was in-depth interviews with informants from 3 plastic companies in East Java, Indonesia, followed by observation and FGD. We carried out Triangulation, member checking, and professional involvement to determine the data’s validity, reliability, and trustworthiness. The results of this study indicated a management system that promotes quality as a business strategy and is oriented towards customer satisfaction by involving all members of the organization. TQM emphasized continuous improvement, customer satisfaction, and employee involvement. By implementing aspects of TQM, plastic packaging companies could improve their production processes and reduce waste, increasing efficiency and profitability. In addition, TQM could also contribute to the company’s green performance by promoting environmentally friendly practices, including using electric machines to replace hydraulic machines, thereby reducing the use of electrical energy and CO2 emissions. The use of solar panels was a step towards green manufacturing. Companies that adopt TQM principles are more likely to implement environmentally friendly initiatives such as reducing energy consumption and using recyclable materials and can demonstrate a commitment to corporate social responsibility. The company’s membership in EcoVadis and SMETA further strengthens the company’s direction towards Green Manufacturing and competitive advantage.

Examining the nexus between carbon dioxide emissions, economic growth, fossil fuel energy use, urbanization and renewable energy towards achieving environmental sustainability in India

Purpose Global urbanization has accelerated due to the persistent trend of rural-to-urban migration in search of better prospects and livelihoods, which has had serious negative effects on the environment, especially in rapidly developing economies. Hence, the purpose of the study is to analyse the relationship between urbanization, economic growth, consumption of renewable energy and carbon emissions with careful examination, particularly in the context of India, where urban population growth has skyrocketed. Design/methodology/approach This study uses econometric methods like Granger causality analysis and the ARDL bound tests, to analyse the intricate relationships between the selected time series variables for India from 1970 to 2022. Findings This research highlights the difficult task of striking a balance between economic development and environmental preservation by emphasizing the crucial role that urbanization and economic expansion play in causing carbon emissions. India’s urbanization trajectory presents a significant policy problem that calls for a move towards renewable energy sources to successfully decrease carbon emissions. Moreover, this research indicates a two-way causal relationship between economic growth, urbanization and carbon emissions, pointing to the intricate interactions between these variables during the developmental stage. Research limitations/implications Despite India’s per capita emissions remaining below the global average, this study highlights the mounting policy challenge of balancing economic development with environmental sustainability as urbanization persists. The paper emphasizes the need for India to invest in renewable energy capacity to replace non-renewable sources and mitigate the carbon footprint of its growing energy demands. Collaborative efforts between India and the developed world to facilitate access to clean energy technologies are crucial for India to achieve sustainable growth in the long run. Originality/value To the best of the authors’ knowledge, existing literature predominantly focuses on investigating the relationship between renewable energy and economic growth, with only a limited number of studies exploring the impact on sustainable development to attain carbon neutrality. Furthermore, these studies have not considered the role of urbanization and non-renewable energy in addressing the challenge of sustainability issues in an emerging country like India. Hence, this study is a comprehensive study that addresses the research gap in these directions.

Wear behaviour of ceramic coating (Al2O3-40%TiO2) in dry condition for automotive applications

The objective of the current research is to examine the effect of varying loads on the wear behaviour of Al2O3-40%TiO2 ceramic coating deposited by flame spray process and to improve material functionality and increase lifecycle in a cost-effective method. To assess the wear behaviour of the deposition, wear test was conducted using a Pin-on-disk tribometer in accordance with ASTM G99 standards. This test was designed to analyse the wear experienced by the coating in practical applications. Surface morphology was examined using field emission scanning electron microscope (FESEM) and energy dispersion spectroscopy (EDS) technique while 3D-profilometer was utilised to further assess the surface roughness of the deposited coating. It was observed that specific wear rate of the deposition exhibited a decreasing trend with increasing load from 40 to 70 N and sliding velocity from 0.4 to 1 m/s. The lowest coefficient of friction was observed at 70 N and 1 m/s. Wear mechanism analysis revealed different types of wear, including abrasion, metal transfer, and brittle fracture, corresponding to the increasing load and sliding velocity. This study is significant for industries that require high-performance coatings for industries such as automotive, aerospace and manufacturing, where high-performance coatings are needed to withstand heavy loads and friction. The current research findings enhance wear resistance and reduce friction, helps manufacturers to adapt coating for specific operational requirements.

Improving On-farm Energy Use Efficiency by Optimizing Machinery Operations and Management: A Review

AbstractThe energy use and emissions from direct fossil fuel combustion on-farms to power farm machinery was critically reviewed. Approximately, 15% of agricultural production costs on-farm are energy-related. A potential solution to more sustainable energy use is a shift toward biofuels from renewable resources. The reduction of greenhouse gas emissions through the substitution of diesel oil with biodiesel depends on the feedstock, the inter-esterification process, the storage period, and ambient conditions. In modern tractors, increased fuel use efficiency (or reduced fuel consumption) has been achieved by power/load matching and the use of variable transmission. Engine management systems that are capable of continuously communicating with the engine and transmission to make appropriate adjustments based on inputs received from the tractor allow for quick and precise responses to changing conditions. As a result, maximum efficiency and productivity can be obtained from the tractor operating similarly to the traditional ‘gear-up and throttle-back’ methods of a proficient operator. The future for autonomous tractors is promising, though not new. Electric-powered tractors are near to commercialization or are already commercially available. Hybrid electric driven tractors present some advantages in terms of increased energy use efficiency and functionalities. Increased efficiency can lead to a reduction in diesel fuel consumption and hence, a concurrent decrease in CO2 emission. Where the local electricity supply has a low-carbon emission factor, this can also result in significant emission reductions. Small light-weight robotic equipment can potentially perform functions currently undertaken by tractor-drawn and other heavy equipment with high-fuel consumption, provided field operating capacity was not compromised. However, the size and weight limitations inherent in current harvesting and transport technology mean that soil compaction will still be a problem with robotic units. The robotic operation of medium-scale equipment within a precision-controlled traffic farming environment should offer more feasible and energy-efficient alternatives.

Synthesis, Structural Aspects, Magnetic, and Adsorption Properties of a Dinuclear Cu (II) Complex Derived From Mixed Ligand Approach

ABSTRACTA dinuclear copper complex, [Cu2(teaH)(pNBA)2(H2O)2]·MeOH·pNBH (1) (where teaH3 = triethanolamine, pNBH = 4‐nitro‐benzoic acid, and pNBA = 4‐nitro‐benzoate) has been prepared and structurally characterized. In 1, there is an interesting intermolecular structure that is shown as a tetramer copper connected in chain‐like motif. In the UV‐Vis spectrum, higher absorbance at 267 nm is referred to n → π* transition, coupled with a weak peak at 500 nm, indicating another transition, which is specified as metal‐to‐ligand charge transfer. The higher intensity peak in the photoluminescence spectrum is marked as the absorption of energy required for the excitation of electrons, whereas lower intensity peaks show the emission of energy, which describes d‐d transitions of Cu (II) electrons due to d9 configuration. Complex 1 was explored for the adsorption of methylene blue (MB) dye, with the maximum adsorption as 101.07 mg/g, whereas the removal efficiency was estimated to be 81.05%. In conformity with the kinetic studies, the adsorption process proceeded via a Pseudo‐first‐order kinetic model. The incorporation of mixed ligands such as teaH3 and pNBH in 1 tends to increase the dimensionality that led to increased MB adsorption. The plausible mechanism behind the adsorption was favored by hydrogen‐bonding, electrostatic, π–π, and n–π* interactions, operating between the dye and complex 1. Further, the H‐bonding and these interactions provided stability to the complex, and an improved dye adsorption was observed even during the 2nd and 3rd recyclability experiments. Additionally, complex 1 corroborated remarkable stability after dye adsorption, allowing for up to four recycling turns. The magnetic study revealed antiferromagnetic coupling between the two magnetic centers with a singlet ground state (S = 0).

Estimating the potential for thermal energy efficiency in the industrial sector: A hybrid model integrating exergy analysis and long-term technology diffusion scenarios

Thermal energy for heating and cooling accounts for a significant portion of the total energy consumed in the industrial sector, and is predominantly provided by fossil fuels. Thus, effective thermal energy management is essential for reducing overall energy consumption, operational costs, and emissions in the industrial sector. While previous studies have explored energy efficiency in this sector, there is a lack of research specifically addressing the challenges of modeling thermal energy efficiency in industry. Therefore, this study proposes a novel hybrid methodological approach that integrates macroeconomic perspectives with detailed end-use analysis and exergy considerations, allowing for a more accurate assessment of recoverable energy in industrial processes in alternative technology diffusion scenarios over a long-term horizon. An empirical study focusing on the pulp and paper subsector in Brazil demonstrated the applicability of the proposed model and revealed significant potential for thermal energy efficiency improvements. The model identified that through optimal technology diffusion scenarios, the sector could achieve up to 25 % reduction in thermal energy consumption by 2050, with heat recovery systems accounting for approximately 40 % of these savings. Cost-effective technology adoption curves indicated that 60 % of this potential could be realized through economically viable investments with payback periods under 3 years. Overall, this study contributes to the field of industrial energy efficiency by offering a hybrid methodological approach that can be adapted to different industrial settings, and can help policymakers and industry stakeholders develop effective strategies to improve thermal energy efficiency and reduce emissions in the industrial sector.

Future technologies for building sector to accelerate energy transition

This Editorial briefly introduces and organizes the worthy studies provided in the Special Issue of Energy and Buildings, entitled “Future technologies for building sector to accelerate energy transition: a special issue”. The main topics of selected papers are herein summarized, proposing scientific studies concerning the next generation buildings, and thus mandatory targets of energy efficiency, reduction of energy demands, novel technologies for building envelope and active energy systems, on-site conversion from renewable energy sources. Both areas of the building industry are considered, and thus decarbonization of existing buildings and novel constructions characterized by mandatory energy performance levels of nearly, net- and plus-energy buildings. These topics are crucial for improving building performance, and reducing energy consumption, with reference to both the heating and cooling seasons, therefore addressing the new and mandatory challenges of zero-energy and zero-emission buildings, also taking into account climate change. The results of manuscripts published in this special issue show worthy potential and real achievements, with significant reductions in energy demands and emissions, and therefore they underline the usefulness of traditional and novel technologies and strategies for buildings, highlighting the economic and environmental benefits of novel design and retrofitting methods and solutions. The debated topics are essential to dealing with climate change, reducing energy poverty, environmental impact, local overheating and UHIs, going, finally, in the direction of a mandatory, sustainable, and smart future for the building sector.

Energy Solutions for Decarbonization of Industrial Heat Processes

The global rise in population and advancement in civilization have led to a substantial increase in energy demand, particularly in the industrial sector. This sector accounts for a considerable proportion of total energy consumption, with approximately three-quarters of its energy consumption being used for heat processes. To meet the Paris Agreement goals, countries are aligning policies with international agreements, and companies are setting net-zero targets. Upstream emissions of the Scope 3 category refer to activities in the company’s supply chain, being crucial for achieving its net-zero ambitions. This study analyzes heating solutions for the supply chain of certain globally operating companies, contributing to their 2030 carbon-neutral ambition. The objective is to identify current and emerging heating solutions from carbon dioxide equivalent (CO2e) impact, economic, and technical perspectives, considering regional aspects. The methodology includes qualitative and quantitative surveys to identify heating solutions and gather regional CO2e emission factors and energy prices. Calculations estimate the CO2e emissions and energy costs for each technology or fuel, considering each solution’s efficiency. The study focuses on Europe, the United States, Brazil, China, and Saudi Arabia, regions or countries representative of companies’ global supply chain setups. Results indicate that heat pumps are the optimal solution for low temperatures, while biomass is the second most prevalent solution, except in Saudi Arabia where natural gas is more feasible. For medium and high temperatures, natural gas is viable in the short term for Saudi Arabia and China, while biomass and electrification are beneficial for other regions. The proportion of electricity in the energy mix is expected to increase, but achieving decarbonization targets requires cleaner energy mixes or competitive Power Purchase Agreement (PPA) projects. Brazil, with its high proportion of renewable energy sources, offers favorable conditions for using green electricity to reduce emissions. The utilization of biomethane is promising if costs and incentives align with those in the EU. Although not the objective of this study, a comprehensive analysis of CAPEX and lifecycle costs associated with equipment is necessary when migrating technologies. Policies and economic incentives can also make these solutions more or less favorable.

The impact of carbon capture, utilization, and storage (CCUS) projects on environmental protection, economic development, and social equity

We present a Dynamic Computable General Equilibrium (DCGE) model to estimate the long-term impacts of CCUS on carbon emission reduction, energy structure, economic growth, and social welfare. Results show that CCUS contributes to optimizing energy structure led by renewable sources and raises the share of clean energy generation to 85.41%–89.84% in 2060. CCUS can help China achieve an earlier peak in carbon emissions and subsequent reductions, with the emission reduction contribution of CCUS estimated at 27.41%–65.00% of total emissions by 2060. Our findings suggest that CCUS has the potential to support China's sustained economic growth, with real GDP rising by 8.82%–18.16% in 2060 compared to the baseline scenario. Additionally, the CCUS fosters growth in social welfare and contributes to mitigating the urban-rural income disparity in the long term. The study broadens the scope of the economic assessment of CCUS and provides valuable insights to enhance comprehension of CCUS's strategic positioning and implementation.

Temperature adaptive thermal storage/release wall based on dynamic spectral control

In response to global climate change, achieving sustainable development through energy conservation and emission reduction has become a common goal for humanity. In this work, we present a general model for computing the energy consumption and carbon emissions of building with low computational complexity and effort. Based on this model, we designed smart green building walls (SGBW), which consist of conventional walls and thermal storage/release films applied to their external/internal surfaces. These films, which incorporate thermochromic materials can adaptively adjust their radiation properties according to environmental temperature. At high temperatures, the thermal storage film(TSF) absorbs heat utilizing a solar absorptance of 0.604 and storing the heat within the wall. Conversely, at low temperatures, the thermal release film(TRF) unidirectionally releases heat into the interior with an infrared emissivity of 0.821. The simulation results indicate that SGBW has enhanced heat storage capacity by 18.7 % and increased heat release capacity by 30.4 % compared to conventional cement walls. In addition, calculations using the general model show that each square meter of SGBW can save 417 ∼ 805 kWh of electricity and reduces CO2 emissions by 225 ∼ 477 kg over the building’s lifecycle in various climatic zones, aligning closely with results obtained from the commercial software. Thus, this model not only simplifies intricate simulation processes but also serves as a guide for designing surface devices. The SGBW is anticipated to be particularly beneficial in buildings located in regions requiring nighttime heating, contributing significantly to indoor temperature regulation while simultaneously reducing energy consumption and carbon emissions.