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Summary: Many electricity consumers around the world are billed electric peak load charges. In the United States, these demand charges can contribute up to 70% of a consumer's electricity bill. Research has shown that the financial impact of these charges to the consumers can be reduced by acting on the intelligence provided by peak electric load day (PELD) forecasts. Unfortunately, published research detailing PELDs forecasting methodologies for facilities adopting behind the meter renewable electricity generation (BTMREG) is non‐existent. This paper contributes: (a) a PELD forecasting methodology applicable to consumers with BTMREG. A case study demonstrates the methodology's ability to achieve 93% of the potential savings in kW, translating to demand charge reductions of approximately US$ 142 129 per year. (b) The first side‐by‐side performance comparisons of electric load and PELD forecasting models for scenarios with and without BTMREG. (c) The first PELD forecasting model savings comparison for scenarios with and without BTMREG. Experimental results suggest that counterintuitively, BTMREG adoption can translate into higher peak load savings for electricity consumers. [ABSTRACT FROM AUTHOR]

Summary: A sustainable, balanced energy portfolio is necessary for a country's continued economic growth. This portfolio must collectively be able to provide reliable, resilient electricity at stable, affordable prices. Nuclear energy is an important contributor to global clean energy supply, both as a primary source and by complementing and enabling other clean energy sources. As we look to the design and operation of future energy systems, we see an increasing need to think differently about how we utilize our energy resources to meet all of our energy needs—not just electricity but also industrial and transportation demands. Resource utilization in light of a broader desire to reduce environmental impacts leads us to consider transforming how we use nuclear energy, which currently provides more than half of the nonemitting electricity generated in the United States. A paradigm shift is required to develop optimal energy generation and use configurations that embrace novel approaches to system integration and process design. The US Department of Energy (DOE) Office of Nuclear Energy (NE) program on Integrated Energy Systems (IES)—formerly the Nuclear‐Renewable Hybrid Energy Systems (N‐R HES) program—was established to evaluate potential options for the coordinated use of nuclear and renewable energy generators to meet energy demands across the electricity, industrial, and transportation sectors. These formerly independent sectors are becoming increasingly linked through technology advances in data acquisition, communications, demand response approaches, and control technologies. Advanced modeling and simulation tools can be employed to design systems that better coordinate across these sectors. Implementation of integrated multi‐input, multi‐output energy systems will allow for expanded use of nuclear energy beyond the grid in a manner that complements the increased build‐out of variable renewable energy generation. These integrated systems would provide enhanced flexibility while also providing energy services and supporting the production of additional, nonelectric commodities (eg, potable water, hydrogen, and liquid fuels) via excess thermal and electrical energy from the nuclear system. Increased flexibility of traditionally baseload nuclear systems will support energy security, grid reliability, and grid resilience while maximizing the use of clean energy technologies. This paper provides an overview of current efforts in the United States that assess the potential to increase utilization of nuclear energy systems, in concert with renewable energy generation, via the IES program. Analysis tools and approaches and preliminary analysis results are summarized, and planned experimental activities to demonstrate integrated system performance are introduced. [ABSTRACT FROM AUTHOR]

Diesel engine generators used at construction sites generate noise, vibration, and large amounts of pollutant emissions. With the strengthening of emission standards for construction equipment, technologies must be developed to meet new requirements. We proposed and analyzed a mobile proton-exchange membrane fuel cell diesel-powered system to address these issues. The proposed system consisted of an autothermal reformer, a proton-exchange membrane fuel cell, and a balance of plant components. Previous studies on the system have not explored the optimal design and operating condition of the system and have not shown whether the proposed system is superior to the system using the hydrogen-fueled proton-exchange membrane fuel cell system in the life-cycle greenhouse gas emissions point of view. In this study, we clarified system operation characteristics, determined the operational design point, and evaluated system performance and life-cycle greenhouse gas emissions. The system was analyzed by constructing a zero-dimensional simulation model. Several control parameters were varied in parametric studies to determine the operational design point (steam-to-carbon ratio of 2, oxygen-to-carbon ratio of 0.5, fuel utilization factor of 0.85, and heat exchanger effectiveness of 0.85). Considering system performance, the determined design point achieved a 32.3% efficiency. Additionally, we assessed the life-cycle greenhouse gas emissions of the system and compared them with those of an alternative system, which is a hydrogen-fueled proton exchange membrane fuel cell system. It was confirmed that in the United States of America, the proposed system emits 1010.2 g-CO2-eq/kWh of greenhouse gas at a 300 km fuel transportation distance, which is similar to a hydrogen-fueled proton-exchange membrane fuel cell system (1001.1 g-CO2-eq/kWh). The proposed system emits less greenhouse gas emissions than the hydrogen-fueled proton-exchange membrane fuel cell system if the distance from the hydrogen production site to the construction site is more than 318 km. Therefore, for a construction site far from a hydrogen production plant, the proposed diesel-fueled proton-exchange membrane fuel cell system is preferable from both the greenhouse gas emissions and convenience perspectives. [ABSTRACT FROM AUTHOR]

Summary: Electricity is an important indicator for economic development, especially electricity production (EP), which is electricity industry managers making strategic decisions. There are many ways to produce electricity, which is the source of rapid growth in EP is rarely studied. Due to the nonstationary and nonlinearity of the EP time series, traditional methods are less robust to predict it. In this study, a novel combination prediction model is proposed based on wavelet transform (WT), long short‐term memory (LSTM), and stacked autoencoder (SAE). Comparisons between the SAE‐LSTM and the advanced prediction model. We compared SAE‐LSTM and the advanced prediction model including BP (Back Propagation) etc. In addition, the performance comparison of the different wavelet layers based on SAE‐LSTM and the performance comparison of the EMD and EEMD based on SAE‐LSTM are also compared. At last, future average growth rates (June 2021 → December 2022) are predicted. The empirical result shows that the combination model in view of SAE‐LSTM exceeds the benchmark models. The results also imply that WT‐SAE‐LSTM outperforms the EMD, EEMD‐SAE‐LSTM, and SAE. Based on the optimal orders and layers of Coiflets combining with SAE‐LSTM, natural gas is the fastest‐growing source of EP in the United States. [ABSTRACT FROM AUTHOR]

Summary: Molybdenum sulfide (MoS2) is one of the active materials used in the fabrication of two‐dimensional supercapacitors devices and has attracted increased attention because of its unique electronic properties with direct bandgap. The exposed active edge sites and large area‐specific surfaces present in MoS2 nanostructures are highly interesting properties of the materials. It was stressed that the preparation methods and composite substrates of MoS2‐based supercapacitors are one of the deciding factors recorded for improving electrochemical performance. This review aims to appraise the preparations, electrochemical studies, and bibliometric analysis of MoS2‐based supercapacitors. The top‐down and bottom‐up methods of preparing MoS2 with the recent electrochemical properties for their supercapacitor devices were highlighted. Likewise, the analysis of the literature related to MoS2‐based supercapacitors that are published between 2007 and 2020 using bibliometric analysis, based on retrieved documents from the Scopus database. The ranking of the authors, institutions, journals, and countries was analyzed to evaluate the quality and influence of their publications using different indicators such as the number of articles, total citations, average citations per year, and H‐index values. The analysis shows that there has been a remarkable increase in the number of publications since 2013. China was found to be a leading country with the highest number of publications related to MoS2‐based supercapacitors and international collaboration influences. The bibliometric results show that the most cited articles are spread across the six countries while the United States has the highest number of citations. This review should serve as a guide for energy researchers to select suitable methods of preparation and appropriate research collaboration through bibliometric studies. Finally, we discussed the opportunities created by MoS2‐based materials as an ingenious platform for advanced storage capacity. Highlights: MoS2 is one of the active materials used in the fabrication of two‐dimensional‐supercapacitors devices and successfully applied in energy storage applications.The exposed active edge sites and large area‐specific surface present in MoS2 nanostructures are highly interesting properties of the materials.Bibliometric analysis of the scientific literature on MoS2‐based supercapacitors was studied.Discussion on the advanced storage capacity of the materials were highlighted.The acceptability of scientometrics in determining the promising areas for future research collaborations were highlighted. [ABSTRACT FROM AUTHOR]