Office of Energy Efficiency and Renewable Energy

Abstract The social housing sector is of great importance in Brazil due to the housing deficit and the need to provide housing for people in situations of economic vulnerability. Recently, the sector has improved its public policies by including requirements to enhance the thermal energy performance of housing. However, given the need for decarbonisation of the residential sector, it is necessary to better understand the performance of these housing units across the different bioclimatic regions in the country. The main goal of this article is to evaluate the influence of more energy-efficient designs for social housing in Brazil, considering CO 2 emissions over the life cycle, in comparison to climate justice-related indicators, such as thermal resilience (thermal autonomy) and energy efficiency (energy consumption over the building’s lifespan). Three representative typologies for social housing in Brazil (single-family, terrace single storey and multi-family) were used to develop several cases considering three possibilities: typical constructions, cases with energy efficiency strategies in the envelope and with cost-benefit optimisation. A total of around 5.500 cases were simulated for the 8 Brazilian bioclimatic zones, resulting in total energy consumption and CO 2 emissions in the life cycle (embodied and operational) of the cases. The methodology considered the use of macro-components and a 50-year building lifespan. Results showed significant differences in the indicators for single-family and multi-family typologies as well as across the different bioclimatic zones. The study provides an initial basis to support the advancement of public policies related to decarbonising the social housing sector in Brazil, a country with significant social inequality and a need for climate justice.

Abstract Background Energy hardship can be broadly understood as a situation in which individuals or households are unable to afford basic energy services necessary for sustaining their wellbeing. Despite conceptual challenges and overlaps with similar narratives (e.g., fuel poverty), the literature on energy hardship continues to expand. It represents a critical intersection with sustainable energy systems that reveals both challenges and opportunities in the transition towards clean energy solutions. However, few energy hardship programmes have been examined from a policy perspective. Our study aims to address this knowledge gap by providing a systematic analysis of a sample of 67 energy hardship programmes implemented across Australia, Canada, the United Kingdom, the United States, and more than 20 European countries. Guided by specific research questions and supported by directed content analysis, we focus on five areas: dominant policy rationales, main policy goals, supportive policy instruments, stakeholders, and key performance indicators (KPIs). Results Despite an important degree of heterogeneity among the reviewed programmes, findings revealed commonalities across significant design and implementation areas. Policy rationales often rely on two significant pillars: narratives related to energy poverty (and related concepts), and market barriers and failures related to energy efficiency or decentralised renewable energy systems. Policy goals encompass three distinct areas: finance, knowledge, and technology/infrastructure. Policy instruments supporting energy hardship programmes are predominantly economic in nature. However, the review of programmes reveals a significant gap in robust estimates of cost-effectiveness or economic efficiency. Results also show that the design and implementation of programmes often involve a diversity of stakeholders. The review reveals that there is an abundance of KPIs that can (potentially) support the monitoring and assessment of programmes. Conclusions Overall, our study reveals significant policy lessons regarding the links, dynamics, and complexities associated with the design and implementation of energy hardship programmes. It underscores the importance of evidence-based evaluations to enhance the ability of policymakers and managers to effectively alleviate the suffering of those facing energy hardship. Results can be of particular interest to countries where policy discussions about energy hardship are emerging, and where there is a need for knowledge to inform decision-making on future programmes that support just and inclusive clean energy transitions.

Purpose. Increasing the thermal efficiency of a multidisciplinary medical center building by optimizing architectural and planning solutions, taking into account climatic conditions and improving the parameters of engineering systems. The building is considered as a single energy system, the efficiency of which is determined by the interaction of external and internal factors. Methodology. Is based on mathematical modeling of heat and mass transfer, analysis of climatic data, and calculation of energy consumption in accordance with current standards. The study takes into account the effects of solar insolation, wind loads, outdoor air temperature, air infiltration, and thermal insulation of building envelopes. An indicator of the efficiency of a design solution is proposed, which assesses its deviation from the energy-optimal variant. Findings. Are based on the example of a multidisciplinary medical center located in the city of Dnipro. An analysis of insolation according to the orientation of facades was carried out, thermal gains through transparent and opaque elements were calculated, and heating and cooling loads were determined. Seasonal climate variability, thermal inertia of materials, and the operational regime were taken into account. The study confirmed that the building’s orientation, glazing area, ventilation system efficiency, and the quality of engineering equipment significantly affect energy consumption. A method for determining the optimal building dimensions is proposed, based on local climatic data and the potential of solar energy. Originality. lies in the substantiation of a systemic approach to energy-efficient design, which combines climatic factors, architectural constraints, and thermal characteristics into a unified model. A coefficient is proposed to evaluate the design solution in terms of its energy efficiency. Practical value. lies in the development of recommendations for reducing energy consumption. The proposed solutions make it possible to reduce thermal loads on engineering systems by 20–25%, lower operating costs, and improve comfort. The examined facility includes a ventilation system with heat recovery (up to 85%) and a heat pump with a COP of 3.5, which resulted in significant energy savings. The results confirm the effectiveness of integrating architectural design with modern engineering equipment and climate adaptation. The methodology can be applied to a wide range of public and residential buildings. Conclusions. Comprehensive energy-efficient design requires the integration of architecture, energy systems, and climatology. The proposed approach enables the development of projects that not only comply with standards but also ensure minimal energy consumption under real operating conditions.

The performance of solar water heater system is assessed by system efficiency and cooling time constant. Computation of these parameters for thermosiphon type solar water heater is given in IS 16368 (2015). In this article, the thermal retention performance is assessed for 100-litre flat plate solar water heater using cooling time constant. The tests conducted for 14 nights with different initial temperatures of water. It was observed that higher the initial water temperature, lower will be the cooling time constant.

Forum papers are thought-provoking opinion pieces or essays founded in fact, sometimes containing speculation, on a civil engineering topic of general interest and relevance to the readership of the journal. The views expressed in this Forum article do not necessarily reflect the views of ASCE or the Editorial Board of the journal.

This document summarizes the progress of VTO Materials R&D projects supported during the fiscal year 2023. The Propulsion Materials portfolio is closely aligned with other VTO subprograms to identify critical materials needs for next-generation high-efficiency powertrains for both heavy- and light-duty vehicles. The Lightweight Materials portfolio works closely with industry through the U.S. DRIVE Partnership to understand light-duty vehicle structural weight-reduction goals and identify technical challenges that prevent the deployment of lightweight materials.

This document summarizes the progress of VTO's Decarbonization of Off-Road, Rail, Marine, and Aviation (DORMA) program during the fiscal year 2023. DORMA's R&D focus was on research, development, and demonstration of new propulsion and vehicle technologies that will reduce greenhouse gas emissions in difficlut-to-decarbonize transportation applications.

Achieving the United States' target of net-zero greenhouse gas emissions by 2050 will require technological transformations and energy sector migration.

The present work’s goal is to develop the analysis of the behaviour of properties as: torque, total losses, magnetic density flux, in the three-phase induction motor with squirrel cage rotor when the material which compound the cage is changed. Aiming this goal, we used simulations of finite elements through the use of software FEMM, and for analysis’ purpose a performance comparison was made between copper and aluminum. Hence, it was noted that the aluminum configuration showed a torque of 454,338 N.m and total power losses equal to 105,71 kW, for cooper was obtained, respectively, the values of 345,219 N.m and 84,66 kW.