α-Amylases are endoenzymes capable of degrading starch into branched and linear oligosaccharides. Since starch-processing industries rely on starch-rich mashes, exploring amylases that can efficiently hydrolyse highly concentrated raw starch is crucial. BaqA from Bacillus aquimaris MKSC 6.2 is particularly promising as it hydrolyses raw starch into simple sugars without preheating, offering potential energy and cost savings for industrial applications. This study investigates the functional role of a specific residue within Conserved Sequence Region (CSR) V of BaqAΔC (a truncated BaqA lacking 34 amino acids from the C terminus), predicted to influence catalytic activity, product specificity, and substrate binding. A BaqA∆CN185D mutant was generated through site-directed mutagenesis and expressed in Escherichia coli ArcticExpress(DE3). Compared with BaqAΔC, the mutant displayed higher specific activity (7.6 ± 0.2 vs. 5.8 ± 0.4 U/mg) and a greater degree of hydrolysis (2.18% vs. 1.41%). Futhermore, BaqAΔCN185D showed a significantly lower Km (9.48 ± 1.3mg/mL) compared to BaqAΔC (23.48 ± 4.8mg/mL), reflecting higher substrate affinity. Its catalytic efficiency (kca.t/Km) also increased from 5.65 ± 0.5 to 9.8 ± 0.9 mL·mg⁻¹·s⁻¹, indicating enhanced substrate binding and overall catalytic performance due to the N185D mutation. HPLC analysis of crude protein extracts from E. coli ArcticExpress (DE3)expressing BaqA∆C and BaqA∆CN185D revealed saccharifying activity, whereas the control strain produced a native liquefying α-amylase. Molecular dynamics simulations further indicated that the N185D substitution altered catalytic and substrate-binding site residues, likely creating a more effective substrate-binding gateway. Collectively, these findings highlight the critical role of N185 in modulating BaqA∆C's catalytic efficiency and product profile, providing valuable insights for industrial enzyme engineering.

Flexible energy consumption patterns and air-conditioning energy-saving potential for rural households in southern China

Mining urban sustainable performance: Unlocking the energy-saving potential of office buildings through smart control technology usage

Energy-saving potential of global optimal strategy for series-parallel hybrid transmissions based on driving cycle generalization

This study addresses the significant disparity between Indonesia's energy conservation policy objectives and their actual implementation, developing a novel framework to promote the adoption of green technology among industrial and small- and medium-sized enterprises (SMEs). Indonesia has pledged to reduce its carbon emissions by 29–41% by 2030 as part of the Paris Agreement; ‎however, it is only utilizing 30% of its energy-saving potential. This means there is an urgent need for comprehensive business models ‎that connect policy and implementation while also addressing complex socio-technical issues. The research utilizes an innovative two-tier methodological framework that combines qualitative with quantitative validation. First, systemic problem structuring employs ‎stakeholder interviews and focus group discussions to delineate policy fragmentation and socio-technical conflicts, facilitated by expert ‎consultations with five industry professionals from Jakarta, Bekasi, and Tangerang. Second, structured questionnaires administered to 303 ‎industrial companies in Jakarta, Tangerang, and Bekasi are checked for validity and reliability before hierarchical regression analysis is used ‎to test organizational readiness factors. Third, participatory solution design utilizes AI-driven sentiment analysis, making it easier to ‎objectively understand qualitative data. It also develops retrofitting finance models that work with the businesses of stakeholders. The two-tier regression and mediation model shows that policy support alone accounts for 42.6% of the variance in performance. When technology ‎awareness, implementation capability, and employee capacity are added, this number rises to 53.6%. The framework validates that effective ‎energy efficiency adoption necessitates the synergistic integration of top-down policy frameworks with bottom-up organizational readiness ‎factors, contesting solely economic models while offering pragmatic insights for Indonesia's 2060 Net Zero objectives and sustainable ‎development goals‎.

As large public buildings requiring expansive spatial environments, public gymnasiums exhibit significant overall energy consumption due to their complex physical structures and usage characteristics. HVAC systems account for a substantial portion of this energy use, making their efficient operation critical for reducing energy consumption in sports facilities. This study employs TRNSYS 18 simulation to construct a model based on the existing heating and cooling source units for an Olympic Sports Center. By altering control strategies, we analyze the energy consumption of units for different seasons to determine operating strategy. Results indicate that, during the cooling season, a sequential start-up strategy for chillers—prioritizing those with the highest COP in response to dynamic terminal load variations—offers 4.72% energy-saving potential during the cooling season. During the heating season, significant energy savings—up to 18.6%—can be achieved by using air-source heat pumps as the base load supply, operating them continuously, and deploying gas boilers only when supplemental heating is required. These findings offer quantitative support for the optimization of HVAC systems in large Public Gymnasiums, demonstrating a viable pathway to substantially improve energy efficiency, reduce operational costs, and advance carbon reduction initiatives, thereby promoting long-term operational sustainability.

Crystallization is a fundamental unit operation in chemical, pharmaceutical, and energy industries, where strict control of crystal size distribution (CSD) is essential for ensuring product quality and process efficiency. However, the nonlinear dynamics of crystallization and the absence of explicit functional relationships between process variables make effective control a significant challenge. This study proposes a hybrid approach that integrates process tomography with deep reinforcement learning (RL) for adaptive crystallization control. A dedicated hybrid tomographic system, combining Electrical Impedance Tomography (EIT) and Ultrasound Tomography (UST), was developed to provide complementary real-time spatial information, while a ResNet neural network enabled accurate image reconstruction. These data were used as input to a reinforcement learning agent operating in a Simulink-based simulation environment, where temperature was selected as the primary controlled variable. To evaluate the applicability of RL in this context, four representative algorithms: Actor–Critic, Asynchronous Advantage Actor–Critic, Proximal Policy Optimization (PPO), and Trust Region Policy Optimization, were implemented and compared. The results demonstrate that PPO achieved the most stable and effective performance, ensuring improved control of CSD and improved control proxies consistent with potential energy savings. The findings confirm that hybrid tomographic imaging combined with RL-based control provides a promising pathway toward sustainable, intelligent crystallization processes with enhanced product quality and energy efficiency.

This study focuses on identifying and quantifying the potential for energy savings in the pharmaceutical industry through a comprehensive energy audit approach. This analysis enabled the identification of electricity usage patterns, assessment of operational efficiency, and evaluation of overall energy performance indicators. The results reveal a consistent year-over-year increase in energy demand, exceeding the projected electricity supply from the grid. These findings highlight the urgent need for energy optimization strategies, such as the adoption of advanced energy management systems, process optimization, and investment in renewable energy integration, to ensure sustainable operations and mitigate the risks of future energy shortages. By providing actionable insights and quantifiable metrics, this research contributes to supporting decision-makers in the pharmaceutical sector in planning energy-efficient operations and aligning with sustainability goals.

In order to study the dyeability and the heat–moisture properties of recycled polyurethane filaments (PUF), a weft-knitted fabric containing recycled materials was developed. The recycled polyester (rPET) yarn was threaded as face yarn and recycled polyurethane filament (rPUF) as ground yarn in the plating stitch fabrics, compared with polyester (PET) and PUF. Four types of knitted fabrics were designed on S 296-2 single-sided knitting machines. The dyeability, air permeability, moisture permeability, and thermal resistance of the four samples were investigated. In addition, the tensile properties and drapability of fabrics were characterized. Results demonstrated that fabrics with recycled materials exhibited superior dyeability, breathability, and moisture permeability versus virgin counterparts. Notably, the dyeing performance was improved significantly under disperse dye dyeing, with the dyeability at 110°C exceeded virgin fabrics at 130°C by >10% ( p < 0.01), highlighting energy-saving potential. The air permeability of recycled fabrics with rPET and rPUF increased by 20% ( p < 0.05), and moisture permeability increased by 15% ( p < 0.05). These findings establish rPUF as a promising material for sustainable sportswear.

Developing reasonable energy management strategy(EMS) to coordinate the working status of various power sources is the key to ascendancy the energy-saving advantages of power-split hybrid electric bus. However, few optimal control strategies have been conducted to utilize operating condition information to achieve approximate online global optimization of energy-saving algorithms, and maximize energy-saving potential. Aiming at the problem, a real-time adaptive EMS based on improved DP algorithm and control rule extraction is proposed for a power-split HEB in this paper. An improved DP algorithm based on secant method for solve the lack of theoretical basis for determining weight coefficients is constructed. The optimal control rules are extracted through outlier detection and graphical method. And an online adaptive algorithm within Relevance Vector Machine and particle swarm optimization algorithm is performed to achieve online adaptive optimal effect. Finally, the simulation and hardware-in-the-loop test are conducted. Simulation results validate that control algorithm proposed in this paper is close to DP results, while achieving the 14.6% oil saving compared with logic threshold control. Additionally, the control algorithm proposed in this paper also demonstrates good real-time performance. The main contribution of this paper is to explore a novel way to fully exert the fuel economy potential and adaptability of power-split HEB in various cycles.

Electrochromic devices (ECDs) offer significant energy-saving potential for applications such as smart windows and displays by modulating optical properties in response to electrical stimuli. However, their widespread adoption is limited by challenges associated with electrolyte stability and the formation of a robust solid-electrolyte interphase (SEI). In this study, a novel quasi-solid polymer electrolyte (QSPE) based on a UV-curable matrix of poly(ethylene glycol) diacrylate (PEGDA) incorporated with poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) [P(VDF-TrFE-CFE), abbreviated as PVTC] is presented. The high dielectric constant of PVTC facilitates lithium-ion transport, while electrochemical cycling triggers partial dehydrofluorination, thereby promoting in situ formation of a LiF-rich SEI layer on WO3 surface. The optimized electrolyte exhibits excellent properties, including high optical transparency (88.7%), ionic conductivity (1.76 mS cm-1), and mechanical robustness. When applied in ECDs, PVTC enables outstanding performance, achieving 86.29% optical retention from the 5000th to the 40 000th cycle and 98.78% charge retention after 50 000 charge-discharge cycles. Furthermore, prototype demonstrations in smart windows and electrochromic sunglasses validate the scalability and flexibility of the proposed system, highlighting a promising strategy for advancing durable, high-performance ECDs through innovative electrolyte design.

The International Maritime Organization (IMO) has introduced new regulations aimed at reducing carbon emissions in the shipping industry. In this study, seven amines were combined with seven phase separation agents to screen three phase-change absorbents that demonstrated distinct phase separation following CO₂ absorption: DETA + n-Butanol + H₂O, DETA + NMP + H₂O, and DETA + DMSO + H₂O. Among these, the DETA + DMSO + H₂O phase-change absorbent outperformed the MEA-based absorbent in both CO₂ absorption capacity (3.17 mol CO₂/kg solvent) and desorption capacity (2.13 mol CO₂/kg solvent), corresponding to improvements of 46% and 12%, respectively. Furthermore, its regeneration energy consumption was only 29% that of MEA. These results demonstrate that the DETA + DMSO + H₂O absorbent offers efficient CO₂ capture performance alongside significant energy-saving potential, making it a promising candidate for onboard carbon capture applications.

Rising global temperatures are driving an urgent need for buildings that consume less energy while maintaining comfort. Cooling demand is surging worldwide, yet conventional air-conditioning remains energy-intensive and carbon-heavy. Against this backdrop, radiative cooling materials have gained attention as a passive solution capable of reflecting incoming solar radiation while emitting thermal energy to the sky. This study aims to establish a climate-informed framework that quantitatively predicts the energy-saving potential of façade-integrated radiative-cooling materials across diverse East Asian climates. By synergizing hour-by-hour building-energy simulation with three novel atmospheric suitability indices, we provide a transferable methodology for selecting and optimizing passive cooling strategies at urban and regional scales. Three façade configurations were tested, i.e., a conventional absorptive surface, a common radiative cooling surface, and an idealized high-reflectance and high-emissivity surface. The results show that the ideal case can reduce wall surface temperatures by up to 20 °C, suppress diurnal heat flux swings by 60–80%, and cut annual cooling demand by 5–80 kWh per square meter, depending on climate conditions. To generalize these findings, three new indices—the Weather Structure Index, Diurnal Temperature Index, and Composite Climate Applicability—were proposed. Regression models with R2 values above 0.9 confirm the Composite Climate Applicability index as a robust predictor of energy-saving potential. The outcomes demonstrate that radiative cooling is not only highly effective in hot, humid regions but also unexpectedly beneficial in clear, cold climates, offering a practical, climate-informed framework for advancing low-carbon building design.

Using energy consumption and other statistical data of a region in Qinghai Province from 2016 to 2022, this study examines the historical energy consumption structure and CO2 emissions of the region. Three scenarios of baseline, energy-saving, and low-carbon were constructed based on the LEAP model to predict and analyze the energy demand and CO2 emissions of the region from 2023 to 2035 under different scenarios. The results showed that: Under the baseline scenario, the total regional energy demand continued to grow, while CO2 emissions showed a trend of increasing and then decreasing and were expected to peak around 2025. Under the conditions of fully tapping the potential of energy conservation and emission reduction in the region and accelerating the green transformation of the industrial and energy consumption structure, the energy demand and carbon emissions in the region could achieve a significant decline in the future. Considering the contributions of the various secondary scenarios, the improvement in end-use energy efficiency will be the most effective option for controlling the total energy demand in both the short and long term. The release of energy-saving potentials on the demand side will effectively reduce the energy intensity of the GDP unit, with an expected energy-saving contribution rate of 59.1% in 2035. Optimizing of the energy consumption structure is the key to controlling the continuous decline in total carbon emissions. Therefore, natural resources should be used to vigorously develop clean energy and improve the electrification level to achieve clean and low-carbon supply side, and the carbon emission intensity per unit of GDP in 2035 is expected to be reduced by approximately 70% compared with that in 2020 under the low-carbon scenario.

As the importance of energy efficiency and smart readiness in the building sector has been on the rise, the financial evaluation of smart-ready technologies (SRTs) remains a gap in this field. This study introduces a methodology that comparatively evaluates the cost–benefit relationship between 11 different SRTs across three European countries—Cyprus, Italy and The Netherlands. Key performance indicators (KPIs) for energy-focused aspects such as Country-Specific Energy Savings Potential (CSESP) and Seasonal Smart Efficiency Coefficient (SSEC) and financial aspects such as Smart Readiness Cost Index (SRCI), Labor Cost Impact Factor (LCIF), Return on Smart Investment (RoSI), and Smart Investment Break-Even Period (SIBEP) were used to quantify the performance of the SRTs. The results indicate that regional labor rates, energy pricing, and climatic conditions—as well as relative technology cost–benefit tradeoffs—play a significant role in the economic viability of smart-ready devices. Having low labor costs and energy pricing, Cyprus exhibited the most cost-effective outcomes among the three countries. Italy showed strong returns although the initial investments were higher. The Netherlands was observed to benefit the most from heating-oriented technologies. The study comes to the conclusion that regionally specific methods are necessary for the adoption of SRTs and that techno-economic performance cannot be assessed separately from local market dynamics. The proposed framework supports stakeholders and policymakers in smart building investment and planning by offering a scalable method for device-level benchmarking. These indicators are developed specifically for this study and are not part of the official EU SRI (Smart Readiness Indicator) methodology. Their inclusion supports device-level evaluation and complements ongoing efforts toward SRI standardization. This research directly addresses Sustainable Development Goal (SDG) 7 on Affordable and Clean Energy, as well as SDG 11 on Sustainable Development, by evaluating how smart-ready technologies can contribute to energy efficiency and decarbonization in buildings. Based on the results, further research is needed to expand the indicator framework to additional technologies, include building typology effects, and integrate dynamic factors such as CO2 pricing and real-time tariffs.

Energy-saving potential by regulating heat pump heating systems in rural areas with latent class analysis

Abstract The aeration process is the largest energy consumer in biological WWTPs, making it one of the most significant operational concerns. This study aims to evaluate the potential energy consumption reduction from upgrading the oxidation ditch (OD) system with the integrated fixed-film activated sludge (IFAS) system in the industrial estate WWTP of PT Jababeka Infrastruktur, Bekasi, Indonesia. The previous OD system was designed for 18,000 m 3 /day, while the newly implemented IFAS system is 14,850 m 3 /day for phase 1. Flow rate and energy consumption operational data were obtained from January–March 2025 (OD) and from 16 June–14 July 2025 (IFAS). Data analysis involved Pearson’s correlation analysis, power trendline model development, and a significance test (t-test). The result showed that in its commissioning phase, IFAS’s potential maximum energy savings reached 39.6% (0.37 reduced to 0.22 kWh/m 3 ) under classification D flow (15,001–16,734 m 3 /day) compared to the OD, with a significant difference between IFAS and OD energy consumption (at all flow classifications or at 1,443–16,734 m 3 /day). These findings are beneficial for PT Jababeka Infrastruktur’s IFAS commissioning evaluation, particularly in efforts to further reduce potential energy consumption or achieve savings.

Abstract A notable portion of greenhouse gas emissions of the built environment originates from the operation of the existing building stock, highlighting the importance of the “renovate or replace” dilemma. This study addresses the dilemma for a range of German multi-family houses (MFHs) by considering the trade-offs among energy efficiency, cumulative (i.e., embodied and operational) CO 2 -eq emissions, and costs. First, five MFHs from different construction periods were selected, modeled, and assigned to typical construction archetypes. Then, the energy consumption, cumulative CO 2 -eq emissions, and costs for various renovation and replacement scenarios, considering different energy technologies, were evaluated over the next twenty-five years. The obtained results suggest that replacement measures have the highest potential for energy savings, while full retrofit measures lead to the most significant decrease in cumulative CO 2 -eq emissions. Due to its considerable reduction in energy consumption, greater climate benefits, and relatively low costs, full retrofit comprising the installation of a heat pump and photovoltaic panels may be the optimal solution for MFHs in Germany.

The main purpose of this study is to investigate potential energy savings by considering two different air-conditioning systems, constant refrigerant flow (CRF) and variable refrigerant flow (VRF) systems, in a new residential compound in Basra, Iraq, where extreme temperature and humidity are observed beside facing a shortage in electrical power supply. One- and two-storey houses were considered, and the initial, installation, maintenance, repair, and energy costs for each AC system were accounted for. The required cooling loads were calculated using Carrier's Hourly Analysis Program (HAP 5.1). The findings revealed that although the VRF system exhibited a higher initial price than the CRF system by 20 % and 41 % for one- and two-storey houses, respectively, its monthly operating cost was lower by 16 % and 19 %, respectively. The energy savings percentage achieved using VRF compared to CRF in the 10th year was 20 % and 22 % in one- and two-storey buildings, respectively. The results demonstrated that implementing VRF systems can save power and minimize electricity waste in residential buildings, which may amount to significant savings in electricity consumption in buildings and compounds constructed in the future

Abstract As the stock of aging buildings increases, renovation is an alternative to demolition and new construction, reducing environmental impacts and material waste. Effective retrofitting should enhance thermal comfort, minimize energy demand, particularly for heating, cooling, and ventilation, and optimize material use. Building on our previous study of Norwegian residential archetypes, we evaluate three retrofit strategies using a bottom-up, physics-based approach. Our findings show that even minimal interventions, such as window replacement, significantly reduce heating demand. However, a more comprehensive retrofit—including external wall and roof insulation, window and door replacement, and balanced ventilation—achieves greater energy savings while maintaining indoor comfort.