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At least 523 records · Page 29

Considerations for Long-Term Load Forecasting in Morocco

There are many factors that determine how demand for electricity may change over time. These factors include GDP, population size, and technology diffusion and adoption. We employ a simple extrapolation of current trends in Morocco GDP to estimate how the peak demand and annual consumption may change through the year 2030. We discuss the many factors that this approach does not take into account (such as adoption of air conditioning, electric vehicles, and distributed generation).

54 ENVIRONMENTAL SCIENCES↗

Considerations for Short-Term Load Forecasting of Morocco

There are many factors that determine how demand for electricity may change over time. The analysis described in this report is focused on using auto-regressive models and neural networks to examine load-forecasting techniques for the next 24 hours.

54 ENVIRONMENTAL SCIENCES↗

Considerations for Medium-Term Load Forecasting in Morocco

There are many factors that determine how demand for electricity may change over time. Medium-term load forecasting is a subset of load forecasting that focuses on the next year. This presentation summarizes analysis performed by NREL on medium-term load forecasting performed for the Moroccan energy system. This analysis includes hourly regressions and load clustering. This work also describes potential next steps that can be implemented by ONEE to improve this medium-term load forecasting.

54 ENVIRONMENTAL SCIENCES↗

Progressive collapse analysis of stiffened panel structure with consideration of actual welding distortion and residual stresses

To date, inclusion of welding distortion and residual stresses in determining the strength of marine structures is based on empirical formulations due to welding complexity. In this study, a more feasible numerical model was developed from the perspective of inherent strain theory. The accuracy of this simplified numerical model was confirmed by transient thermo-elastic–plastic finite element analysis using a novel dynamic mesh refining and iterative substructure method which is 50 times faster than conventional finite element method. Welding distortion by the two numerical approaches was validated with experimental measurement. The collapse analyses indicated that the inherent strain model predicted a compressive strength and load-displacement curve with high accuracy, as validated by the transient thermo-mechanical model. The global stiffness and the ultimate strength of the welded structure would be overestimated by about 22% if no welding effects were considered. The proposed computation procedure for determining the ultimate strength of welded structures is accurate, simple, and practical and enables improvement of ultimate strength through optimization of welding joint design to reduce the welding residual stress and distortion.

Huang, Hui↗

Considerations when Implementing Shift Work in Nuclear Operations

Many domestic and international nuclear facilities have processes that require personnel to work on some type of shift. Shift work has many different schedules such as night, morning, swing, and rotating shift. Some common shifts are DuPont, Pitman, and Panama. There are many psychological and physiological impacts to a person working shifts. These impacts can affect work performance, safety, and security within an organization. A well-established nuclear organization relies on a strong security culture that implements a trustworthiness or reliability program. The IAEA defines this type of program as individuals meeting the highest standards of reliability, trustworthiness, and physical and mental suitability. Psychological and physiological impacts that apply to a Trustworthiness Program are reliability (an individual’s ability to adhere to security and safety rules and regulations) and physical and mental suitability. If shift work isn’t properly implemented in Facility Operations, then several issues or human factors can arise. An employee that suffers from a poorly designed shift, gets overworked, or doesn’t have the proper rest period implemented, may suffer from shift work disorder, acute fatigue, or cumulative fatigue. Introducing fatigue into Facility Operations can have severe consequences to security, safety, production, and cost. Another challenge of shiftwork within a facility is laziness and complacency. Creating an atmosphere where the employee is willing to admit fatigue to his or her supervisor is a challenge. It is up to the organization to do the needed research on shift work and to implement the best shift for their facility and personnel.

Stockwell, Brandon↗

Land Use Considerations for Large-Scale Solar

Energy development is the largest driver of land-use and land-cover change in the United States. Today, one of the leading forms of this new development is large-scale solar photovoltaic (PV) plants. This new issue brief is intended to educate local governments and community stakeholders interested in supporting solar development. Topics covered include: 1. Key challenges posed by storm water runoff and mitigation measures that can be incorporated into project development processes. 2. Vegetation Management concepts and their tactical application, including an Integrated Vegetation Management (IVM) strategy. Together, these strategies can help communities and local governments develop policies and guidelines on large-scale solar that can realize both environmental and economic benefits.

14 SOLAR ENERGY↗

Land Use Considerations For Large-Scale Solar

Energy development is the largest driver of land-use and land-cover change in the United States. Today, one of the leading forms of this new development is large-scale solar photovoltaic (PV) plants. This new issue brief is intended to educate local governments and community stakeholders interested in supporting solar development. Topics covered include: 1. Key challenges posed by storm water runoff and mitigation measures that can be incorporated into project development processes. 2. Vegetation Management concepts and their tactical application, including an Integrated Vegetation Management (IVM) strategy. Together, these strategies can help communities and local governments develop policies and guidelines on large-scale solar that can realize both environmental and economic benefits.

14 SOLAR ENERGY↗

Performance Considerations for Ground Source Heat Pumps in Cold Climates: Preprint

Remote, cold climates present challenges to finding safe and affordable options to heat homes. In Alaska, residential ground source heat pumps (GSHPs) have been gaining in popularity to fill this gap. However, there is little research on their long-term performance or effect on soil temperatures. The extended heating season and cold soils of Alaska provide a harsh testing ground for GSHPs, even those designed and marketed for colder climates. The large and unbalanced heating load of cold climates creates a challenging environment for GSHPs. In 2013 the Cold Climate Housing Research Center (CCHRC) installed a GSHP at its Research and Testing Facility (RTF) in Fairbanks, Alaska. The heat pump replaced an oil-fired condensing boiler heating a 464 m2 office space via an in-floor hydronic radiant heating system. The ground heat exchanger (GHE) was installed in moisture-rich silty soils underlain with permafrost near 0°C. The intent of the installation was to observe and monitor the system over a 10-year period in order to develop a better understanding of the performance of GSHPs in sites with permafrost and to help inform future design. As of this writing, the heat pump system has been running for seven heating seasons. The efficiency in those seven heating seasons has been variable with ups and downs that have been difficult to explain. This paper seeks to understand the variability in performance as well as make recommendations for GSHP use in other cold climates.

cold climate↗