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We summarize the feasibility of using geothermal energy from the Western Canada Sedimentary Basin (WCSB) to support communities with populations >3000 people, including those in northeastern British Columbia, southwestern part of Northwest Territories (NWT), southern Saskatchewan, and southeastern Manitoba, along with previously studied communities in Alberta. The geothermal energy potential of the WCSB is largely determined by the basin’s geometry; the sediments start at 0 m thickness adjacent to the Canadian shield in the east and thicken to >6 km to the west, and over 3 km in the Williston sub-basin to the south. Direct heat use is most promising in the western and southern parts of the WCSB where sediment thickness exceeds 2–3 km. Geothermal potential is also dependent on the local geothermal gradient. Aquifers suitable for heating systems occur in western-northwestern Alberta, northeastern British Columbia, and southwestern Saskatchewan. Electrical power production is limited to the deepest parts of the WCSB, where aquifers >120 °C and fluid production rates >80 kg/s occur (southwestern Northwest Territories, northwestern Alberta, northeastern British Columbia, and southeastern Saskatchewan. For the western regions with the thickest sediments, the foreland basin east of the Rocky Mountains, estimates indicate that geothermal power up to 2 MWel. (electrical), and up to 10 times higher for heating in MWth. (thermal), are possible.

In this work, three-dimensional thermal simulations of single 18650 lithium-ion battery cell and 75 V lithium-ion battery pack composed of 21 18650 battery cells are performed based on a multi-scale multi-domain (MSMD) battery modeling approach. Different cooling approaches’ effects on 18650 lithium-ion battery and battery pack thermal management under fast discharging and external shorting conditions are investigated and compared. It is found that for the natural convection, forced air cooling, and/or mini-channel liquid cooling approaches, the temperature of battery cell easily exceeds 40 °C under 3C rate discharging condition. While under external shorting condition, the temperature of cell rises sharply and reaches the 80 °C in a short period of time, which can trigger thermal runaway and may even lead to catastrophic battery fire. On the other hand, when the cooling method is single-phase direct cooling with FC-72 as coolant or two-phase immersed cooling by HFE-7000, the cell temperature is effectively limited to a tolerable level under both high C rate discharging and external shorting conditions. In addition, two-phase immersed cooling scheme is found to lead to better temperature uniformity according to the 75 V battery pack simulations.

Reduced order models (ROMs) are increasingly applied to entrained flow gasification development due to reduced computational requirements relative to computational fluid dynamics (CFD) models. However, they require greater a posteriori knowledge of the reactor physics. A significant parameter influencing ROM outputs is the jet half-angle of the solid fuel and oxidant mixture in the gasifier. Thus, it is important to understand the geometry of the jet in the gasifier, and how it is dependent on operating parameters, such as solid and carrier gas flow rates. In this work, an existing model for jet half-angles, which considers the ratio of surrounding gas density to jet core density, is extended to a dry solids jet with impinging gas. The model is fitted to experimental jet half-angles. The jet half-angle of a non-reactive flow was measured using laser-sheet imaging for solid fluxes in the range of 460–880 kg/m2·s and carrier gas fluxes in the range of 43–90 kg/m2·s at the transport line outlet. Jet half-angles ranged from 5.6° to 11.3°, increasing with lower solid/gas loading ratios. CFD simulations of two reactive conditions, with solid and gas fluxes similar to experiments, were used to test the applicability of the proposed jet half-angle model.

Numerical calculations are performed to determine the potential of using one-dimensional transparent photonic crystal heat mirrors (TPCHMs) as transparent coatings for solar receivers. At relatively low operating temperatures of 500 K, the TPCHMs investigated herein do not provide a significant advantage over conventional transparent heat mirrors that are made using transparent conducting oxide films. However, the results show that TPCHMs can enhance the performance of transparent solar receiver covers at higher operating temperatures. At 1000 K, the amount of radiation reflected by a transparent cover back to the receiver can be increased from 40.4% to 60.0%, without compromising the transmittance of solar radiation through the cover, by using a TPCHM in the place of a conventional transparent mirror with a In2O3:Sn film. For a receiver operating temperature of 1500 K, the amount of radiation reflected back to the receiver can be increased from 25.7% for a cover that is coated with a In2O3:Sn film to 57.6% for a cover with a TPCHM. The TPCHM that is presented in this work might be useful for high-temperature applications where high-performance is required over a relatively small area, such as the cover for evacuated receivers or volumetric receivers in Sterling engines.

The campus of the Karlsruhe Institute of Technology (KIT) contains several waste heat streams. In an effort to reduce greenhouse gas emissions by optimizing thermal power consumption on the campus, researchers at the KIT are proposing a ‘DeepStor’ project, which will sequester waste heat from these streams in an underground reservoir during the summer months, when the heat is not required. The stored heat will then be reproduced in the winter, when the campus’s thermal power demand is much higher. This paper contains a preliminary geochemical risk assessment for the operation of this subsurface, seasonal geothermal energy storage system. We used equilibrium thermodynamics to determine the potential phases and extent of mineral scale formation in the plant’s surface infrastructure, and to identify possible precipitation, dissolution, and ion exchange reactions that may lead to formation damage in the reservoir. The reservoir in question is the Meletta Beds of the Upper Rhein Graben’s Froidefontaine Formation. We modeled scale- and formation damage-causing reactions during six months of injecting 140 °C fluid into the reservoir during the summer thermal storage season and six months of injecting 80 °C fluid during the winter thermal consumption season. Overall, we ran the models for 5 years. Anhydrite and calcite are expected mineral scales during the thermal storage season (summer). Quartz is the predicted scale-forming mineral during the thermal consumption period (winter). Within ~20 m of the wellbores, magnesium and iron are leached from biotite; calcium and magnesium are leached from dolomite; and sodium, aluminum, and silica are leached from albite. These reactions lead to a net increase in both porosity and permeability in the wellbore adjacent region. At a distance of ~20–75 m from the wellbores, the leached ions recombine with the reservoir rocks to form a variety of clays, i.e., saponite, minnesotaite, and daphnite. These alteration products lead to a net loss in porosity and permeability in this zone. After each thermal storage and production cycle, the reservoir shows a net retention of heat, suggesting that the operation of the proposed DeepStor project could successfully store heat, if the geochemical risks described in this paper can managed.

Novel carbon materials, carbon nanotubes (CNTs) and porous graphene (PG), were exploited and used as conductive additives to improve the rate performance of LiMn2O4 cathode for the rechargeable aqueous Zn/LiMn2O4 battery, namely the rechargeable hybrid aqueous battery (ReHAB). Thanks to the long-range conductivity and stable conductive network provided by CNTs, the rate and cycling performances of LiMn2O4 cathode in ReHAB are highly improved—up to about 100 mAh·g−1 capacity is observed at 10 C (1 C = 120 mAh·g−1). Except for CNTs, porous graphene (PG) with a high surface area, an abundant porous structure, and an excellent electrical conductivity facilitates the transportation of Li ions and electrons, which can also obviously enhance the rate capability of the ReHAB. This is important because the ReHAB could be charged/discharged in a few minutes, and this leads to potential application of the ReHAB in automobile industry.

The purpose of this investigation was the development of a new colloidal route for the fabrication of Mn3O4 electrodes for supercapacitors with enhanced charge storage performance. Mn3O4-carbon nanotube electrodes were fabricated with record-high capacitances of 6.67 F cm−2 obtained from cyclic voltammetry tests at a scan rate of 2 mV s−1 and 7.55 F cm−2 obtained from the galvanostatic charge–discharge tests at a current density of 3 mA cm−2 in 0.5 M Na2SO4 electrolyte in a potential window of 0.9 V. The approach involves the use of murexide as a capping agent for the synthesis of Mn3O4 and a co-dispersant for Mn3O4 and carbon nanotubes. Good electrochemical performance of the electrode material was achieved at a high active mass loading of 40 mg cm−2 and was linked to a reduced agglomeration of Mn3O4 nanoparticles and efficient co-dispersion of Mn3O4 with carbon nanotubes. The mechanisms of murexide adsorption on Mn3O4 and carbon nanotube are discussed. With the proposed method, the time-consuming electrode activation procedure for Mn3O4 electrodes can be avoided. The approach developed in this investigation paves the way for the fabrication of advanced cathodes for asymmetric supercapacitors and multifunctional devices, combining capacitive, magnetic, and other functional properties.