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Building energy codes are essential tools for achieving energy efficiency in buildings. However, the full energy savings potential of these codes can only be realized if buildings are constructed in compliance with them. Therefore, evaluating building energy code compliance is crucial in bridging the gap between the energy efficiency requirements set by energy codes and the actualized energy savings achieved. An energy code compliance evaluation serves as a mechanism to assess construction practices, evaluate the effectiveness of code enforcement, identify gaps in compliance, and guide strategies for improvement through training and education. Conducting code compliance evaluation activities involves field studies that require careful design and significant resources. Historically, more emphasis has been placed on developing and adopting building energy codes, while efforts to evaluate compliance have been relatively limited and lacking consistent approaches. The passage of the 2009 American Recovery and Reinvestment Act (ARRA), which mandated that states create plans for achieving 90% compliance within eight years, stimulated the need for an energy code compliance evaluation. As a result, federal, state, and local governments, and utilities have invested in the development of methodologies and tools for code compliance evaluation studies. This paper reviews the code compliance evaluation studies conducted in the United States over the past three decades. It describes and compares the methodologies and metrics used to assess building energy code compliance, summarizes the general elements and steps involved in the evaluation process, and discusses common issues in these studies. Over time, code compliance evaluation methodologies have evolved from isolated development within individual states, regions, and utilities, to widely accepted protocols applicable across different states and local jurisdictions. There has been a transition in compliance metrics, shifting from historical compliance rates to energy-consumption-oriented approaches. [ABSTRACT FROM AUTHOR]

Energy efficiency improvement is often hindered by the energy efficiency gap. This paper examines the effect of short-run temperature fluctuations on the Energy Star air conditioner purchases in the United States from 2006 to 2019 using transaction-level data. Results show that the probability of purchasing an Energy Star air conditioner increases as the weekly temperature before the transaction deviates from 20–22 °C. A larger response is related to fewer cooling degree days in the previous years, higher electricity prices/income/educational levels/age/rate of owners, more common use of electricity, and stronger concern about climate change. 1 °C increase and decrease from 21 °C would lead to a reduction of total energy expenditure by 35.46 and 17.73 million dollars nationwide (0.13% and 0.06% of the annual total energy expenditure on air conditioning), respectively. Our findings have important policy implications for demand-end interventions to incorporate the potential impact of the ambient physical environment. The probability of purchasing an energy-efficient air conditioner increases as the temperature deviates from 20–22 °C in the United States, with the response varying by electricity price, background climate, and demographic characteristics. [ABSTRACT FROM AUTHOR]

In recent years, the urgency to address climate challenges has driven the need to achieve net-zero carbon goals by 2050. The construction industry, as a major contributor to carbon emissions, plays a vital role in achieving this target. While numerous net-zero energy building approaches have been proposed globally, there is limited comparative research between developed and developing countries. This study aims to address this research gap by selecting the top three carbon-emitting countries in the world - China, India, and the United States (US) - as the research subjects. Through a comparison of their net-zero energy building approaches and typical cases, it is evident that there exists a significant disparity between developed and developing nations. Specifically, differences are observed in the following aspects: net-zero building approaches in the United States have an earlier start and involve collaborations between the government and multiple organizations, while China and India started relatively later and rely primarily on government initiatives. China's consideration of applicable building types in net-zero approaches is not inclusive enough, particularly lacking coverage on industrial buildings. It is encouraging to observe that China and India pay more attention to embodied carbon emissions compared, while their decarbonization strategies for embodied carbon emissions are not as comprehensive as those in the United States when it comes to actual building applications. Regarding carbon offset options, the United States and India demonstrate more comprehensive considerations, while China currently lacks consideration for off-site power generation and negative carbon technologies. The United States boasts a larger number of net-zero buildings, most of which have been certified through the country's own net-zero building approaches. In contrast, China and India have fewer certified net-zero buildings, and only a small percentage have been certified using their own methods, especially in China. The technologies employed in zero‑carbon buildings in the United States are more advanced compared to China and India. These findings underline how the disparities in economic levels between developed and developing countries are reflected in net-zero building approaches. Based on these insights, professionals in the field can develop tailored strategies to bridge the gap in net-zero building development between developed and developing nations. This study provides a foundation and recommendations for achieving carbon neutrality in the construction industry for the world's top three economies by 2030. • Limited research on net-zero building approaches in developed vs. developing countries • Disparities in net-zero energy building approaches between China, India, and the United States • Differences in net-zero building initiation, government collaborations, and building types • Varied emphasis on embodied carbon emissions and decarbonization strategies • Contrasting considerations for carbon offset options and advanced technologies [ABSTRACT FROM AUTHOR]

Informed by literature on collaboration, policy adoption, and utility governance, this paper develops and empirically tests hypotheses addressing the implications of collaboration, utility ownership and city-level commitment to sustainability on city-level clean energy policy decisions. This paper offers an answer to the question, "to what extent does collaboration between utilities and local governments influence policy adoption." We utilize cross-sectional data from the United States focused Integrated City Sustainability Database (ICSD) to perform an ordinary least squares regression analysis that investigates the degree that specific city attributes and state policy influence the creation of city-scale policy. This analysis shows that cities with a Publicly Owned Utility (POU) adopt close to two energy policies more than similar cities served by an IOU. Higher levels of collaboration among cities and with an Investor Owned Utility (IOU) can offset a portion of the adoption gap for community-oriented energy policy, but has little to no impact on governmental or renewable policies. [ABSTRACT FROM AUTHOR]

The water‐soluble copper(II)‐lanthanum(III) complex based on phenylalaninehydroximate ligands La(H2O)4[15‐MCCuPhalaha‐5](Cl)3 (1) has been synthesized and characterized structurally and spectroscopically. The X‐ray structure of 1 demonstrated that the ring copper ions are placed in distorted square pyramidal geometries with various axial coordination ligands. UV/Vis absorption spectra reveal halochromic behavior of 1 in the aqueous solution which represents reversible color changes from blue to colorless in response to pH variations. This effect has been described as pH‐induced "on‐off‐on" switch through protonation and deprotonation of the phenylalaninehydroximate ligands in the metallamacrocyclic complex 1. To investigate the electronic structures of the complexes as well as the plausible mechanism of the halochromism, DFT calculations on the La(H2O)4[15‐MCCu(II)Phalaha‐5]3+ ion and the protonated La[15‐MCCu(II)Phalaha(H)‐5]4+ species were carried out. The calculations demonstrate that the protonation of the phenylalaninehydroximate ligands in the metallacrown is accompanied by variations in the electron density distribution and HOMO‐LUMO energy gap, which correlate with the spectroscopic changes observed. [ABSTRACT FROM AUTHOR]

Highlights • Energy performance gaps exist in green commercial buildings. • Organizational, behavioral and engineering factors could be responsible. • Surveys from facility managers in the United States were obtained. • LEED buildings are associated with factors more likely to cause the gap. Abstract Energy performance gap refers to the discrepancy between the predicted and the realized energy savings after buildings adopt energy-efficient technologies. This study identifies and analyzes the organizational, behavioral and engineering factors related to the energy performance gap. 117 completed surveys from facility managers in the United States were obtained in 2017. We find that the primary reasons for the energy performance gap are (1) occupants using more energy than designed, (2) more occupants than originally designed, and (3) energy-efficient technology failures. An analysis is conducted using probit models. The results show that LEED and Energy Star buildings are more likely to have tenant lease agreements to eliminate asymmetric information for new tenants. Energy Star buildings are more likely to have sub-metering for air conditioning. However, LEED buildings are associated with factors causing the energy performance gap, such as lack of sub-metering for AC and longer operating hours. Building characteristics such as occupancy rate, building type, ownership and building location influence the impacts of the identified socio-technical factors. Finally, several suggestions to mitigate the energy performance gap are proposed, such as incentives to facility managers, commissioning, energy performance contracting, and occupants' behavioral change. [ABSTRACT FROM AUTHOR]

Silicon carbide and gallium nitride, two leading wide band gap semiconductors with significant potential in electric vehicle power electronics, are examined from a life cycle energy perspective and compared with incumbent silicon in U.S. light-duty electric vehicle fleet. Cradle-to-gate, silicon carbide is estimated to require more than twice the energy as silicon. However, the magnitude of vehicle use phase fuel savings potential is comparatively several orders of magnitude higher than the marginal increase in cradle-to-gate energy. Gallium nitride cradle-to-gate energy requirements are estimated to be similar to silicon, with use phase savings potential similar to or exceeding that of silicon carbide. Potential energy reductions in the United States vehicle fleet are examined through several scenarios that consider the market adoption potential of electric vehicles themselves, as well as the market adoption potential of wide band gap semiconductors in electric vehicles. For the 2015-2050 time frame, cumulative energy savings associated with the deployment of wide band gap semiconductors are estimated to range from 2-20 billion GJ depending on market adoption dynamics. [ABSTRACT FROM AUTHOR]

• Structural, electronic, magnetic properties of orthorhombic PrCuO 3 perovskites scrutinised by DFT. • Computed structural parameters are in good accord with corresponding experimental data. • Energetically-favoured anti-ferromagnetic ordering of bulk PrCuO 3 is promoted. • Semi-conducting nature of bulk orthorhombic PrCuO 3 perovskites established. • Computed band gap of most stable AF state is 1.39 eV, indicating potential high degree of suitability for solar-energy applications. We performed Density-Functional Theory calculations on the recently-synthesised perovskite PrCuO 3 structure. PBE + U and hybrid-DFT (HSE06) calculations reveal that the PrCuO 3 -structure energy bands cannot cross the Fermi level in the Total Density of States – indicating semi-conducting behaviour. The bond geometries and bond angles agree well with their experimental counterparts. We have explored magnetic-momentum states in the pattern of the Pr and Cu magnetic moments along the [1 1 1] direction – elucidating that screening of different magnetic ordering shows that antiferromagnetic (AFM) order is more energetically favoured. Optical-absorption spectra computed HSE06 indicate PrCuO 3 ′s potential solar-energy and technological interest. [ABSTRACT FROM AUTHOR]

The adsorption of highly toxic carbon monoxide molecule (CO) on pristine, Al, Si, and Ga-doped phagraphene are studied using Density Functional Theory (DFT) calculations at M06-2X level of theory with 6-311G++ (d,p) basis set, to explore the potential abilities of phagraphene as an effective CO detection sensor. The full relaxed geometries of CO molecule, pristine and doped phagraphenes and related CO/pristine and doped-phagraphene complexes are specified and the variety parameters such as energy of Highest Occupied Molecular Orbital (E HOMO), energy of Lowest Unoccupied Molecular Orbital (E LUMO), gap energy (E g), energy of adsorption (E ad), basis set superposition error (BSSE), gap energy alterations percent (%ΔE g), Global Electron Density Transfer (GEDT), energy of Fermi level (E F), work function (Φ), work function alterations percent (%ΔΦ), Density of States (DOS) patterns and Molecular Electrostatic Potential (MEP) profiles were calculated and analyzed. The results demonstrate that the CO molecule has a very poor physical adsorption on the pristine phagraphene. The calculated E ad value of CO/Si-doped phagraphene complex (−4.2043 kcal/mol) is moderate, however, the calculated %E g value (+2.3498%) shows that Si-doped phagraphene has a low sensibility to CO molecule. The E ad calculations also indicate that the adsorption of CO molecule on Ga-doped phagraphene (E ad = −6.9653 kcal/mol) has the shorter recovery time compared with Al-doped phagraphene (E ad = −8.1450 kcal/mol). Therefore, Ga-doped phagraphene can be considered as an promising gas sensing platform for detecting CO molecule. Image 104 • Variety adsorption complexes of CO on pristine, Al, Si, and Ga doped phagraphene surface were studied. • The E HOMO , E LUMO, E g , E ad , ΔE g , E F , Φ, %ΔΦ, GEDT, DOS plots and MEP were calculated for each case at M06-2X/6-311G++(d,p) level of theory. • The sensitivity and recovery time for Ga-doped phagraphene is suitable for fast detection. • Results showed that the Ga-doped phagraphene can be applied as a promising nanosensor for the detection of CO molecule. [ABSTRACT FROM AUTHOR]

In keeping with the theme "50 Years of the Dielectrics and Electrical Insulation Society," the first article is "50+ Years of Intrinsic Breakdown" by Ying Sun, Clive Bealing, Steven Boggs, and Ramamurthy Ramprasad all of the University of Connecticut, Storrs, Connecticut, USA. The article reviews the theory of intrinsic breakdown of solids beginning from von Hippel's 1932 postulate, that breakdown occurs when electrons gain more energy from the electric field than they lose energy to the lattice, up to the present quantum mechanical concepts. Using von Hippel's criterion for intrinsic breakdown, the article shows correlation of the intrinsic breakdown with both bandgap and phonon cutoff frequency with measured data for a range of both ionic and covalently bonded materials, through the use of computational quantum mechanics from first principles. Moving forward from intrinsic breakdown to engineering breakdown of materials with chemical impurities and defects, Monte Carlo computations are being pursued. [ABSTRACT FROM AUTHOR]

The author comments on the quantification of energy gap in obesity epidemic of the present population in the U.S. The author mentions that scientists are alarmed because numerous human beings experienced weight gain and they believed this is associated with the positive balance of energy needed in achieving healthy weight. Moreover, the calculation of energy gap and how it impacts the weight of human beings are also stated.