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BackgroundSmart grid tools (e.g., individualized disaggregated data, goal setting, and behavioural suggestions/feedback) increase opportunities to reduce or shift residential electricity consumption, but can they shape residential energy culture? And what underlying factors influence this shift? Insights are identified from a qualitative analysis of a 3-year residential smart grid project in a suburb of Toronto, Canada. Interviews evaluated whether participants experienced changes in their energy culture and identified underlying factors. In particular, the impacts of the project tools on participants’ norms (attitudes and awareness towards energy management), material culture (technical changes) and energy practices (conservation/peak shifting actions) were assessed, and motivations and barriers towards energy management were identified. The effectiveness of engagement mechanisms (i.e., web portal, reminder emails, webinars, incentivized control programme, and weekly electricity reports) was also evaluated. By examining detailed qualitative feedback following a multi-year suburban smart grid project in Ontario this study aims to (1) assess the changes in energy culture over the duration of the 3-year project and to (2) assess the underlying factors influencing household energy consumption and a smart residential energy culture.
ResultsFindings from the interview were compared to the results of an initial project survey to identify longer-term influences on energy culture. Increases in self-reported awareness and practices were accounted for, with the web portal and individualized weekly feedback email reported most frequently as causes of change. While increased awareness was obtained, participants needed additional guidance to make substantial changes. Although participants were financially motivated, norms of lifestyle and convenience, as well as competing household values of energy management were the largest barriers to home energy management.
ConclusionsThis study showcases challenges for engaging homeowners with home energy management technologies due to norms as well as competing household interests. Nuanced findings as an outcome of this study framed around energy cultures can influence future studies on smart grid engagement and consumer behaviour with larger samples sizes. In particular, future studies can further investigate the motivations and barriers surrounding residential energy cultures, how to engage different ‘cultures of consumption’ within households, and elements to effectively educate consumers beyond disaggregated feedback.
[en] Highlights: • Fuel economy for Fuel Cell Hybrid Power Systems using optimal and sub-optimal strategies. • Fuel economy using Real-Time Optimization strategies with current slope limiter. • 6 kW fuel cell under static feed-forward and load-following control is the reference. • Fuel economy is obtained in the entire range of load demand for proposed strategies. • Up to 5 L fuel economy for optimal strategy compared to sub-optimal ones. - Abstract: The aim of this paper is to compare an optimal and a sub-optimal strategy for the Fuel Cell Hybrid Power Systems based on Maximum Power Point tracking algorithms (with global feature or not) with the basic energy management strategy, namely the static Feed-Forward strategy considered as reference. The fuel economy is used as the unique performance indicator. The gaps in fuel economy for two Real-Time Optimization strategies based on Global Extremum Seeking algorithm and Perturb & Observe algorithm are compared to highlight the advantages of the global optimization strategies. Up to 5 L fuel economy was obtained for optimal strategies compared to sub-optimal ones. Also, the gaps in fuel economy are estimated for the proposed strategies using two levels of the FC current slope. The results of this study obtained for constant load are validated on a variable and unknown profile of the load power as well.
[en] Highlights: • We presents an energy management for thermoelectric generators to handle different load conditions. • The threshold control based on the bus voltage intervals is introduced for the energy management. • The LPT based on fuzzy logic is applied when the system power demand is low. • The MPPT is realized based on the open-circuit voltage method when system power demand is high. - Abstract: Thermoelectric generators (TEGs) can be widely applied to directly convert thermal energy into electricity. Herein, we propose an energy management system for TEGs to achieve efficient energy storage and use. Specifically, we consider both the generally unstable power generation given the variable temperature difference between the hot and cold sides of TEGs and the variable load that requires the inclusion of a storage unit consisting of a battery and supercapacitor for improving the system performance. The supercapacitor mitigates energy fluctuations and reduces transients in the bus voltage, and the battery acts as a backup energy source, storing energy and delivering electricity when the load power demand is high. In addition, we propose a novel threshold control strategy based on the bus voltage intervals for the energy management system that incorporates maximum power point tracking (MPPT) and load power tracking (LPT) to maintain energy balance among the system units. MPPT aims to provide an efficient collection of thermal energy, and LPT based on fuzzy logic is used to maintain a stable bus voltage when the DC load power demand is low. The experimental results verify that the proposed LPT approach regulates the evaluated variations in DC load power with an average error of 3.5% and that the energy management properly operates under variable load power and battery state of charge.
[en] Highlights: • We shed light on the link between energy management and renewable supply chains. • We collected original data from manufacturing firms in Malaysia. • We found that energy awareness was the strongest predictor of strong renewable energy supply chains. • We found that managing renewable energy supply chains enables companies to achieve competitiveness. • We discussed the implications for energy policy in emerging economies. - Abstract: Drawing from the resource-based view (RBV) and complexity theories, we test the effects of energy management practices on renewable energy supply chain (RESC) initiatives in 151 certified (ISO 14001 and ISO 50001) manufacturing firms in Malaysia. Our results showed three dimensions of energy management practices (EMP) – top management commitment, energy awareness, and energy auditing – which were positively associated with the development of RESC initiatives. We found that insufficient knowledge of energy efficiency means firms struggle to manage energy effectively, constraining opportunities such as converting waste into energy to support business’ targets. Our work has implications for energy policy. For example, we suggest that the transfer of energy efficiency management knowledge and technology from multinational to local companies could help to improve energy usage, and that local companies could generate renewable energy through supply chain networks. The findings of this work shed light on how to further develop energy efficiency policy in emerging economies, with implications for academics, practitioners and decision-makers. This work makes the case for an integrated discussion of energy management and renewable energy supply chains.
[en] Highlights: • Advanced infiltration technique for solid oxide regenerative fuel cells is introduced. • Highly active and thermally stable nanocatalysts are produced via in operando synthesis. • Geometric properties and crystallization behavior are precisely regulated at high temperatures. • Nano-tailoring of catalysts remarkably improves the performance in both fuel cell and electrolysis modes. • Nanocatalysts do not degrade during long-term operation under harsh environments. Solid oxide regenerative fuel cells (SORFCs), which perform the dual functions of power generation and energy storage at high temperatures, could offer one of the most efficient and environmentally friendly options for future energy management systems. Although the functionality of SORFC electrodes could be significantly improved by reducing the feature size to the nanoscale, the practical use of nanomaterials has been limited in this area due to losses in stability and controllability with increasing temperature. Here, we demonstrate an advanced infiltration technique that allows nanoscale control of highly active and stable catalysts at elevated temperatures. Homogeneous precipitation in chemical solution, which is induced by urea decomposition, promotes crystallization behavior and regulates precursor redistribution, thus allowing the precise tailoring of the phase purity and geometric properties. Controlling the key characteristics of Sm0.5Sr0.5CoO3 (SSC) nanocatalysts yields an electrode that is very close to the ideal electrode structure identified by our modeling study herein. Consequently, outstanding performance and durability are demonstrated in both fuel cell and electrolysis modes. This work highlights a simple, cost-effective and reproducible way to implement thermally stable nanocomponents in SORFCs, and furthermore, it expands opportunities to effectively exploit nanotechnology in a wide range of high-temperature energy devices.
[en] Highlights: • A microgrid model with non-convex combined heat and power systems is considered. • Microgrid variables are optimally scheduled by a simultaneous-distributed algorithm. • The proposed method shows a fast convergence for a test system with 408 variables. • Cost saving is larger than that of a particle swarm optimization approach. - Abstract: This paper proposes a distributed energy management system-based algorithm to solve the optimal schedule of multiple combined heat and power systems in which exponential efficiencies of fuel cells are considered. To deal with the variation in fuel cell efficiencies, the proposed algorithm utilizes the alternating direction method of multipliers, consensus theory, and quadratic programming to solve the optimization problem with constant efficiencies. Then, the efficiency matching is checked iteratively to verify the obtained result. The optimization algorithm is constructed in a whole-day distributed form, such that all time slot variables can be solved simultaneously in a distributed way. With the help of this simultaneous solution method, operation of hot tanks and combined heat and power systems can be scheduled globally. The proposed algorithm is tested successfully with a test system having 4 combined heat and power systems, showing fast convergence in numerous simulations.
[en] Setting-up and running a systematic process for investigating and analyzing the status and issues and offering effective ways for improving the performance of the Korea-OECD/NEA cooperation. - Establishing and operating a systematic process, implementing the gradual strategies - Analyzing the organizational as well as operational characteristics of OECD/NEA. - Analyzing activities and performance of Korean delegations and participants, and studying the ways to improve their performance. - Publishing an annual report. The committee for the selection of candidates joining in the two schools selected nine candidates for the WNU RT School and five candidates for the IAEA Nuclear Energy Management School. Thereafter, the project will support expense for joining in the schools such as tuition, flight cost, accommodation, meals, etc.
[en] Highlights: • Reheating effect in fused deposition modeling is universal but primarily happens in layer thickness direction. • Printing speed is predicted to be positively correlated to mechanical properties. • Temperature setting is a primary concern in fused deposition modeling. • Strict energy management is required if a fused deposition modeling printer of higher resolution is to be invented and applied. An adaptable three-dimensional transient mathematical model of temperature variation with respect to space and time, during and after the fused deposition modeling (FDM), is proposed and applied with a boundary-adjusting finite difference method. This model enables researchers to study the influence of almost all other parameters on the temperature field and gradient variation when constructing any cuboid at fixed raster angle of 0(90)° and filling ratio of 100%. Some predicted but significant conclusions are reached: reheating of a deposited raster by a newly deposited one is universal and happens mainly in the layer thickness direction; temperature settings are the primary and direct factors determining temperature field variation, while layer thickness and printing speed can still exert their own influence; printing speed is predicted to be positively correlated to mechanical properties of FDM constructed components through the mechanism of thermal coalescence; strict energy management is required if a FDM printer of higher resolution is to be invented and applied. The technique of such mathematical model can provide immediate insights in the understanding of FDM process from the perspective of energy balance, many of which have never been revealed from previous reports yet.
[en] In this paper, the author highlights and discusses four factors which weigh on the use of electric power, and are related to obstacles to an efficient climate policy. The first one is the non respect of the European directive on the assessment of building energy performance in the DPE (this is adverse to electric heating). The second one is the RT 2012 thermal regulation which is inefficient for the reduction of CO2 emission and of energy consumptions, and favours natural gas. The third one is a social injustice which results from an undue tax (the CSPE) which has been multiplied by 4,5 since 2016 and affect housings and office premises which are using electric heating. The fourth one is the assessment of thermal and climate performance of these housings which in fact depreciates their property value