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The University of Newcastle (UON) and Jord International Pty Ltd. (Jord) have jointly developed a novel concept for the storage of energy from renewable and fossil fuel sources. The process, referred to as the pressurized regenerative calcium cycle (PRC2), relies on cyclic carbonation and calcination of CaO/CaCO3, in which low-cost electrical energy (i.e., off-peak, or excess generation from renewables) drives the calcination reaction and electricity is generated as required through the carbonation reaction. Initial proof-of-concept testing of the process was previously conducted within an existing fluid bed reactor at UON. The PRC2 concept was successfully demonstrated by maintaining the fluid bed reactor at a constant temperature by using the heat released during the reaction of calcium oxide and carbon dioxide. Following proof-of-concept testing, further refinement of the PRC2 process, which is the subject of this paper, was conducted to address its shortcomings and, importantly, facilitate the detailed design, construction, and operation of a large-scale demonstration plant. Nine different configurations were examined for the PRC2 process, for each of which a combined experimental, process modelling, and techno-economic assessment was completed. Experimental investigations were conducted to determine the suitability of carbonate materials for the PRC2 process. Process modelling and levelized cost of storage (LCOS) calculations were concurrently conducted and revealed that the molten salt approach (Option 9) was the most promising, having superior round-trip efficiency and lowest LCOS. For practical reasons (e.g., technical difficulties of working with molten salts), Option 3 (indirect power generation using a fluid bed reactor) was deemed the most feasible option for a demonstration scale plant. The LCOS for Option 3 (assuming a 100 MWe capacity) was calculated to be AUD 245 per MWh, which is on par with the cost of batteries for peak power replacement applications (the cost associated with lithium-ion batteries is AUD 370 per MWh). [ABSTRACT FROM AUTHOR]

System failure in large-scale electrolyzer and fuel cell installations may cause the formation of explosive H2–air–steam mixtures. Detonation properties (e.g., detonation cell size) and flame dynamics features (e.g., flame acceleration, runup distance, and deflagration-to-detonation transition "DDT") of these mixtures were investigated experimentally and numerically to gain a more in-depth understanding of the hazards of H2–air–steam under conditions pertinent to PEM-based electrolyzers and fuel cells (temperatures between 50 °C and 80 °C and pressures between 20 and 40 bar). While our results confirm the findings of previous studies in terms of the cooling effects of steam on detonation, we found that operating pressures between 20 and 40 bar counteract the effect of steam, making the H2–air–steam mixture more detonable. This is particularly evident from the experimental data on detonation cell size and runup distance at pressures greater than 20 bar. [ABSTRACT FROM AUTHOR]

The objective of this study is to compare the ignition and burning characteristics such as burnout times of volatiles and char, and ignition mechanism of single pulverized coal particle burning in air (O2/N2) and oxy (O2/CO2) environments. An entrained flow reactor with photo detector has been employed for this study. This technique involves online monitoring of radiation emission from an individual coal particle. Individual particles of sub-bituminous or lignite coal particle with size in the ranges of 106-125 micron and 180-212 micron particles have been injected into an air (O2/N2) or oxy (O2/CO2) environment inside an entrained flow reactor. The oxygen concentration in the ambient gas is varied between 10%-50% by volume. The volatile and char burnout times have been obtained from time histories estimated from the radiation emitted by the particle. The results show an obvious increase in the burning rates of volatiles and char with increasing oxygen concentration. Further, when compared to N2 atmosphere, the burning rate and radiation intensity are found to be lower in CO2 atmosphere, especially at lower oxygen concentrations. An indication of the possible ignition mechanism has been outlined from the percentages of single and double peaks observed in the radiation emission histories. The complete experimental investigation shows that the burning rates of both volatiles and char are predominantly affected by the oxygen concentration, particle size and gas temperature. The theoretical results from a single particle model has been used to validate the trends and the combustion durations obtained from the present experimental study and is published as a separate manuscript. [ABSTRACT FROM AUTHOR]

Building design is important for saving energy and reducing GHG emissions by applying passive solar heating and cooling design principles and using the right materials and appropriate design tools. This will make the home healthier and more comfortable. The design of energy efficient and sustainable buildings is critical for the future. A key aspect of any design is the realistic and accurate prediction of the performance of the building under a wide range of weather conditions. This paper examines the effect of different climate zones in Australia (which are comparable to the world's major climates) on the thermal performance of a complete building and recommended design techniques to suit each climate zone to enhance the overall thermal performance. To examine the effect of the location (different climates) on the overall thermal performance and how a good design in one location may not be suitable at another location, AccuRate will be used to assess the thermal performance for the exact module in different climates zones to allow a fair comparison to find the appropriate design for the climate where the building is located. Also, in this research, each climate zone design requirements and techniques were addressed for various climate variables (including: solar radiation, rainfall, wind speed and direction and humidity) to design sustainable building which save great amount of energy while sustaining occupants thermal comfort.