Advanced concept of energy system for space heating, hot water preparation in new family buildings has been developed. Energy system consists of innovative heat pump (5.5 kW) extracting the heat from ...two environments: ground and ambient air. Heat pump is coupled with simple seasonal ground storage of heat built under the house and with photovoltaic system (6 kW) installed on the roof. In case of excess photovoltaic (PV) electricity in summer, the heat pump with variable speed compressor adapts its electric power to PV system power, extracts the heat from ambient air and transfers the heat into seasonal ground storage without external electric energy input. The ground storage is charged to 30 °C in upper level during the summer. In winter, heat pump uses the heat from ground storage and transfers it through the heat pump cycle for space heating with high effectivity. The experimental system has been installed in newly built house in Hamry (CZ) and it is operated for two seasons so far. Results from the monitoring show radical reduction of electricity use from external grid. System uses more than 80 % of energy from renewables. Specific non-renewable primary energy use for space heating, hot water preparation and auxiliary energy is about 15 kWh/m2 per year.
Buildings are a major contributor to climate change, accounting for one third of global energy consumption and one quarter of CO2 emissions. However, comprehensive information is lacking for the ...development, evaluation and monitoring of mitigation policies. This paper discusses the remaining challenges in terms of reliability and consistency of the available data. A review of energy use in buildings is presented to analyse its evolution by building types, energy services and fuel sources. Residential buildings are the most consuming, although tertiary expansion requires further analysis to develop sound specific indicators. Heating Ventilation and Air Conditioning (HVAC) systems concentrate 38% of buildings consumption, calling for strengthened standards and incentives for retrofitting. Electrification is rapidly increasing, representing a potential tool for climate change mitigation, if renewable power was promoted. However, energy use in buildings will only curb if global cooperation enables developing nations to break the link between economic growth, urbanisation and consumption. To this aim, efficiency gains both in construction and equipment, decarbonisation of the energy mix and a global awareness on energy conservation are all needed.
•Buildings account for a third of global consumption and a quarter of CO2 emissions.•HVAC accounts for 38% of buildings consumption, equivalent to 12% of final energy.•Population, wealth and urbanisation in emerging nations are the key upward drivers.•Energy intensity gains require retrofitting and adopting conservation behaviours.•Building’s electrification is far and pointless until the power sector is decarbonised
Hydrogen has emerged as a new energy vector beyond its usual role as an industrial feedstock, primarily for the production of ammonia, methanol, and petroleum refining. In addition to environmental ...sustainability issues, energy-scarce developed countries, such as Japan and Korea, are also facing an energy security issue, and hydrogen or hydrogen carriers, such as ammonia and methylcyclohexane, seem to be options to address these long-term energy availability issues. China has been eagerly developing renewable energy and hydrogen infrastructure to meet their sustainability goals and the growing energy demand. In this review, we focus on hydrogen electrification through proton-exchange membrane fuel cells (PEMFCs), which are widely believed to be commercially suitable for automotive applications, particularly for vehicles requiring minimal hydrogen infrastructure support, such as fleets of taxies, buses, and logistic vehicles. This review covers all the key components of PEMFCs, thermal and water management, and related characterization techniques. A special consideration of PEMFCs in automotive applications is the highlight of this work, leading to the infrastructure development for hydrogen generation, storage, and transportation. Furthermore, national strategies toward the use of hydrogen are reviewed, thereby setting the rationale for the hydrogen economy.
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Decarbonizing the planet is one of the major goals that countries around the world have set for 2050 to mitigate the effects of climate change. To achieve these goals, green hydrogen that can be ...produced from the electrolysis of water is an important key solution to tackle global decarbonization. Consequently, in recent years there is an increase in interest towards green hydrogen production through the electrolysis process for large-scale implementation of renewable energy-based power plants and other industrial, and transportation applications. The main objective of this study was to provide a comprehensive review of various green hydrogen production technologies especially on water electrolysis. In this review, various water electrolysis technologies and their techno-commercial prospects including hydrogen production cost, along with recent developments in electrode materials, and their challenges were summarized. Further some of the most successful results also were described. Moreover this review aims to identify the gaps in water electrolysis research and development towards the techno-commercial perspective. In addition, some of the commercial electrolyzer performances and their limitations also were described along with possible solutions for cost-effective hydrogen production Finally, we outlined our ideas, and possible solutions for driving cost-effective green hydrogen production for commercial applications. This information will provide future research directions and a road map for the development/implementation of commercially viable green hydrogen projects.
•Water electrolysis is one of the most promising methods for green hydrogen generation.•Green hydrogen provides a sustainable solution for future energy demands and decarburization.•This review summarizes various water electrolysis technologies for techno-commercial perspective and their challenges.•Finally, we outlined our ideas/recommendations for future research and developments.
This review presents a critical combined energy analysis of demand in developed/developing countries, including the load requirements of the various business sectors. It summarizes on-demand ...time-series, energy supply, overall trade in gas, oil, electricity, coal, and renewable energy (e.g., wind, solar, geothermal, tidal, etc.) as well as global carbon dioxide (CO2) emissions. The duration of the review is selected between the energy supply and demand forecast from 1990 to 2040. Multi-energy approaches include primary energy generation, consumption, gross domestic product (GDP) energy intensity, the total trade balance of crude oil production, production of natural gas, trade balance and use of natural gas, production of lignite and coal, demand for trade in lignite and coal, generation and use of electricity, the share of renewables in power generation, total percentage of solar energy. Geographic coverage covered the global energy demand of the Organization for Economic Co-operation and Development (OECD), the group of seven (G7), Brazil, Russia, India, China, and South Africa (BRICS), European Union, Europe, North America, Commonwealth of Independent States (CIS), Asia, Latin America, Pacific, Middle-East and Africa. Market individuals and cooperative policymakers communicate in a variety of ways: our review and its impact on energy trade, social development, economic and climate change, which is then presented in a deeper way, in the future energy outlook. The findings of the review make it clear that there is a great deal of future global energy demand until 2040 in different situations: new aspects of policymaking, the requirement is about 15% lower in the 450-scenario, and 10% higher in the current energy policy scenario.
•This study contributes to a comprehensive analysis of energy supply and demand forecasts from 1990 to 2040.•It covers the total global energy demand, including developed/developing countries.•It provides a time-series analysis of total trade, oil, electricity, coal, RES, and global CO2 emissions.•The positions of the world’s main energy player will change significantly in 2040.
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