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Cooling in the industry sector contributes significantly to the peak demand placed on an electrical utility grid. New electricity tariff structures include high charges for electricity consumption in peak hours which leads to elevated annual electricity costs for high-demanding consumers. Demand side management (DSM) is a promising solution to increase the energy efficiency among customers by reducing their electricity peak demand and consumption. In recent years, researchers have shown an increased interest in utilizing DSM techniques with thermal energy storage (TES) and solar PV technologies for peak demand reduction in industrial and commercial sectors. The main objective of the present study is to address the potential for applying optimization-based time-of-use DSM in the industry sector by using cold thermal energy storage and off-grid solar PV to decrease and shift peak electricity demands and to reduce the annual electricity consumption costs. The results show that when cold thermal energy storage and solar PV are coupled together higher annual electricity cost savings can be achieved compared to using these two technologies independently. Additionally, considerable reductions can be seen in electricity power demands in different tariff periods by coupling thermal energy storage with off-grid solar PV. [ABSTRACT FROM AUTHOR]

Buildings contribute to climate change by consuming a considerable amount of energy to provide thermal comfort for occupants. Cooling energy demands are expected to increase substantially in the world. On this basis, technologies and techniques providing high energy efficiency in buildings such as passive cooling are highly appreciated. Passive cooling by means of phase change materials (PCM) offers high potential to decrease the cooling energy demand and to improve the indoor comfort condition. However, in order to be appropriately characterized and implemented into the building envelope, the PCM use should be numerically analyzed. Whole-building energy simulation tools can enhance the capability of the engineers and designers to analyze the thermal behavior of PCM-enhanced buildings. In this paper, an extensive review has been made, with regard to whole-building energy simulation for passive cooling, addressing the possibilities of applying different PCM-enhanced components into the building envelope and also the feasibility of PCM passive cooling system under different climate conditions. The application of PCM has not always been as energy beneficial as expected, and actually its effectiveness is highly dependent on the climatic condition, on the PCM melting temperature and on the occupants behavior. Therefore, energy simulation of passive PCM systems is found to be a single-objective or multi-objective optimization problem which requires appropriate mathematical models for energy and comfort assessment which should be further investigated. Moreover, further research is required to analyze the influence of natural night ventilation on the cooling performance of PCM. [ABSTRACT FROM AUTHOR]

Globally, a considerable amount of energy is consumed by the building sector. The building envelope can highly influence the energy consumption in buildings. In this regard, innovative technologies such as thermal energy storage (TES) can help to boost the energy efficiency and to reduce the CO 2 emissions in this sector. The use of phase change materials (PCM), due to its high heat capacity, has been the centre of attention of many researchers. A considerable number of papers have been published on the application of PCM as passive system in building envelopes. Researches have shown that choosing the PCM melting temperature in different climate conditions is a key factor to improve the energy performance in buildings. In the present paper, a simulation-based optimization methodology will be presented by coupling EnergyPlus and GenOpt with an innovative enthalpy-temperature (h-T) function to define the optimum PCM peak melting temperature to enhance the cooling, heating, and the annual total heating and cooling energy performance of a residential building in various climate conditions based on Köppen-Geiger classification. Results show that in a cooling dominant climate the best PCM melting temperature to reduce the annual energy consumption is close to the maximum of 26 °C (melting range of 24–28 °C), whereas in heating dominant climates PCM with lower melting temperature of 20 °C (melting range of 18–22 °C) yields higher annual energy benefits. Moreover, it was found that the proper selection of PCM melting temperature in each climate zone can lead to notable energy savings for cooling energy consumption, heating energy consumption, and total annual energy consumption. [ABSTRACT FROM AUTHOR]

To date, the energy flexibility assessment of multicomponent electrical and thermal systems in residential buildings is hindered by the lack of adequate indicators due to the different interpretations, properties, and requirements that characterise an energy flexible building. This paper addresses this knowledge gap by presenting a fundamental energy flexibility quantification framework applicable to various energy systems commonly found in residential buildings (i.e., heat pumps, renewables, thermal and electrical storage systems). Using this framework, the interactions between these systems are analysed, as well as assessing the net energy cost of providing flexibility arising from demand response actions where onsite electricity production is present. A calibrated white-box model of a residential building developed using EnergyPlus (including inter alia a ground source heat pump, a battery storage system, and an electric vehicle) is utilised. To acquire daily energy flexibility mappings, hourly independent, and consecutive demand response actions are imposed for each energy system, using the proposed indicators. The obtained flexibility maps give insights into both the energy volumes associated with demand response actions and qualitative characteristics of the modulated electricity consumption curves. The flexibility potential of each studied energy system is determined by weather and occupant thermal comfort preferences as well as the use of appliances, lighting, etc. Finally, simulations show that zone and water tank thermostat modulations can be suitably combined to shift rebound occurrences away from peak demand periods. These insights can be used by electricity aggregators to evaluate a portfolio of buildings or optimally harness the flexibility of each energy system to shift peak demand consumption to off-peak periods or periods of excess onsite electricity generation. • Few studies evaluate energy flexibility from an integrated energy systems perspective. • A novel unified framework is proposed for capturing the DR potential of thermal and electrical systems. • A series of novel indicators are introduced to acquire daily energy flexibility mappings. • Flexibility maps are used to quantify energy flexibility concisely and consistently. • Weather, occupant schedules and use of appliances shape the flexibility potential of each system. [ABSTRACT FROM AUTHOR]

• PCM passive system was coupled with natural ventilation. • PCM melting temperature was optimized in different climate zones. • Airflow rates were numerically calculated based on the wind and buoyancy effects. • Two control strategies were implemented to maximize the utilization of ventilation. In recent years, the building sector has been responsible for continuous increase in energy consumption in the world. Space heating and cooling accounts for 34% of this energy consumption in buildings. In this context, using thermal energy storage (TES) can reduce energy consumption for space air conditioning. The use of phase change materials (PCM) as latent heat thermal energy storage (LHTES) system in the building envelope has been of great interest for passive cooling applications due to the high energy storage capacity of this technology. However, in order to utilize the full potential of a PCM, it needs to be fully charged at each cycle. Ventilation during the night is an effective method which can be used in PCM-enhanced office buildings with the aim of charging the PCM every required cycle. In the present study, PCM melting temperature of office building in various climate conditions was optimized using a simulation-based optimization and coupled with free cooling operation. Ventilation control strategies were used to improve the cooling energy performance of the PCM enhanced building integrated into envelopes. It was found that charging PCM with night ventilation, especially when using some specific control strategies of natural ventilation operated by external windows opening results in considerable cooling energy savings. The study was conducted for 15 different cities around the world. It was found that, in hot arid conditions, PCM passive cooling system was ineffective. Although, the energy savings were improved by coupling PCM and natural ventilation in these climate conditions. But the benefits were more or less similar to using natural ventilation only. On the other hand, in temperate condition, the effectiveness of PCM was increased from 3.32% to 25.62% by coupling a PCM passive system with night ventilation. It was further improved to 40% when using PCM with temperature-controlled ventilation. Moreover, it can be said that smart control of ventilation can lead to considerable energy savings. [ABSTRACT FROM AUTHOR]

• TABULA home archetypes are white-box modelled with realistic occupant variables. • Model parameters narrow the gap between calculated and measured energy use to 5–10%. • In temperate climates, measured heat energy is 22–32% below steady-state simulation. • Deep retrofit of an old home with modern boiler achieves up to 60% energy savings. • Shallow retrofit of a modern home achieves climate action target with heat pump only. Recent climate action plans set ambitious targets for large-scale home energy retrofit. These retrofit targets also recommend switching from oil boilers to electrical heat pumps. One area-based approach to retrofit is neighbourhood scale. Ideally with local community participation, neighbourhood retrofit improves a group of structurally similar homes, of the same archetype. Defined home archetypes already exist for 20 European countries thanks to previous research. That same research attempted steady-state calculations of space heating energy using the ISO 13790 Seasonal Method. Those calculations diverged from measured energy use by a large gap. Taking example home archetypes from Ireland, this study narrowed this energy-use gap by incorporating realistic parameters and schedules. Physical white-box models were constructed in DesignBuilder, and simulated by EnergyPlus with local weather data. The simulations combined realistic heating schedules, internal gains, infiltration and ventilation; converging simulation energy use with typical measurements and mostly achieved model calibration indices. Therefore, the resultant energy-use data was capable of tuning future grey-box models to investigate home energy use across ranges of heating patterns and heating setpoints. The aims of this study are threefold. First, devise a repeatable method to produce heat energy-use values by simulating white-box models of home archetypes, that enable tuning of future grey-box models. Second, specify the heating variables that result in acceptable energy-use gaps between simulation of home archetype models and their typical measurements. Third, test if the retrofits of three Irish home archetypes under a typical occupant schedule, achieve national climate action targets. [ABSTRACT FROM AUTHOR]

Phase Change Materials have been acknowledged for their potential to be used as passive strategy for improving energy efficiency and occupants' thermal comfort in buildings. However, their performance still needs to be enhanced to have them effectively used. In this view, this study investigates the potential improvement of PCMs performance for passive cooling application by efficient natural ventilation in residential building stock. Therefore, coupled dynamic simulation and optimization analysis is performed to explore the optimum melting temperature of PCM integrated in the external building envelope to minimize cooling loads in different Italian climate zones. Moreover, various natural ventilation control strategies are implemented to assess their influence on the process of PCM charge-discharge cycle. Results show that PCM inclusion in the building envelope provides significant cooling savings, up to about 300 kWh/year in mild climates. Furthermore, both night and temperature controlled natural ventilation are able to enhance the efficiency of PCMs thermal energy storage charge-discharge cycle. However, the optimum performance is obtained by coupling PCMs with natural ventilation controlled by indoor/outdoor temperature difference in all considered climate contexts. Accordingly, considerable building cooling energy need reduction is achievable through the optimum combination of PCMs and natural ventilation control, especially in milder climates. • PCM passive cooling performance coupled with natural ventilation control is studied. • Summer optimum PCM melting temperature is explored via optimized dynamic simulation. • PCM is included in the building envelope in various Italian climate zones. • PCMs provide significant passive cooling contribution, especially in mild climates. • PCM coupled to T-controlled natural ventilation further improves energy saving. [ABSTRACT FROM AUTHOR]

Based on the key metrics to monitor energy sector improvements from the International Energy Agency (IEA), transport emissions must decrease 43% by 2030. Freight logistics operations in Europe are struggling with ways to reduce their carbon footprints in order to adhere to regulations on governing logistics, while providing the increasing demand for sustainable products from the customers. This study investigates the anonymised microdata from the European Road Freight Transport Survey (2011–2014) to acquire patterns in logistic operations based on over 11 million journeys within 27 EU and EFTA countries involved. Different algorithms were implemented (Horizontal Cooperation, Pooling and Physical Internet) to analyse efficiency, in terms of vehicle utilisation, degree of vehicles' loading during each journey and sustainability in terms of the amount of C O 2 emissions per journey. This study shows that existing data can provide invaluable information on the efficiency of logistics operations and the positive effects data analytics can provide. Physical Internet algorithm has performed better in terms of reducing emissions and improving the logistics' efficiency, especially when the sample sizes are large, but this would require a shift to an open global supply web. [ABSTRACT FROM AUTHOR]