Requirements for Interdependent Reserve Types Providing Primary Frequency Control.
Abstract not provided.
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Abstract not provided.
For presentation at GSA Connects 2023, Pittsburgh, PA, October 15-18, 2023.
This report is purposed to provide a summary of the local climate and data from meteorological (Met) towers and wind profilers at the East Tennessee Technology Park (ETTP), the Y-12 National Security Complex Site (Y-12), the Oak Ridge National Laboratory (ORNL), as well as other federal, state, or local agencies as necessary to support the natural phenomena hazards (NPH) analysis 10-year update required by Department of Energy (DOE)- STD-1020-2016, Natural Phenomena Hazards Analysis and Design Criteria for DOE Facilities. The data from this report will be used to support high wind analyses, precipitation analysis, flood analysis, lightning analysis, and other severe weather phenomena for the ETTP, the ORNL, and Y-12.
Over the course of this project, we have successfully de-risked our distributed microgrid control architecture by tightly integrating its associated control algorithms into a unified software library, installing the software library on several industrial-grade target hardware platforms, and validating the performance of the resulting microgrid controller in a real-life microgrid. Upon completion of the project, we demonstrated that our distributed control architecture is resilient against (i) failures in control devices, (ii) unreliable communication links, (iii) delays in transmitted data, and (iv) imperfect knowledge of the number of (and state of) generation and load assets in the microgrid. In this final report, we present results from all the milestones that were accomplished over the course of this project.
The effects of raw water leaching at the U.S. SPR were modeled using SANSMIC. In addition to 18 caverns identified in previous leaching reports, six caverns have been identified for further monitoring based on the results of this report. SANSMIC continues to serve as a useful tool for monitoring changes in cavern shape. However, some caverns where string cuts were made in the middle of drawdowns are showing overprediction in the SANSMIC model when compared with recent sonars.
This report provides an analysis of the effects of raw water leaching at the U.S. SPR using the Sandia Solution Mining Code (SANSMIC). A new version of the code has been established in the past year (implemented in Python and C++ code) and was used for this annual report. Additionally, the setup, running, and post-processing of leaching modeling has now been streamlined into a single Python notebook environment for each cavern run.
This report provides an analysis of the effects of raw water leaching at the U.S. SPR during calendar year 2025 using the Sandia Solution Mining Code (SANSMIC). The setup, running, and post-processing of leaching modeling has now been streamlined into a single Python notebook environment for each cavern run. A comprehensive investigation of nearest neighbor cavern distances is included.
Abstract not provided.
Not Available
Understanding the ecological dynamics of zooplankton communities is crucial to precisely assessing the health of marine ecosystems and their management. Metabarcoding has contributed to a better understanding of biodiversity in marine environments. However, this methodology still requires protocol optimisation. Here, we used a complementary approach combining molecular and morphological identification methods to identify the zooplankton community inhabiting the Berlengas Archipelago, Portugal. The presence of non-indigenous species was also assessed. The results showed that the metabarcoding approach outperformed the classical morphological identification method, detecting more species with higher resolution. Nevertheless, the classical method was able to identify species that were not detected by the molecular approaches, probably due to a lack of reference data in the databases. The comparison between different molecular approaches showed that COI and bulk DNA gave better results than 18S rRNA and eDNA by detecting higher species diversity. However, complementarities were observed between them. Molecular tools also proved effective in identifying several potential non-indigenous species, identifying, for the first time, several potentially unreported NIS inhabiting the Portuguese marine ecosystems. Overall, our results confirmed the importance of combining both classical and molecular methods to obtain a more refined assessment of the zooplanktonic communities in marine environments.
A system and method for control of dispatchable resources on an electrical power distribution grid is disclosed. The disclosed method provides improved response to power imbalance based on a communications signal independent of system frequency. The communication signal provides a feed-forward control of dispatchable power resources. A communications network is employed to generate a signal to dispatchable resources that a power imbalance has occurred. Due to fast response power transmission network interfaces associated with the dispatchable resources, the respective resources respond in significantly less time than feedback controlled conventional generators which depend on line frequency sensing. The rapid response mitigates the impact of power imbalances and enables greater penetrations of converter-interfaced power generation units such as renewable energy sources to be connected to the grid.
Abstract not provided.
Abstract not provided.
Republic of Korea has unique geographical characteristics similar to those of an island, resulting in an isolated power system. For this reason, securing sufficient operating reserves for the system’s stability and reliability in the face of the intermittency of increasing variable renewable energy (VRE) is paramount, and this will pave the way to achieving the nation’s decarbonization target and carbon neutrality. However, the current reserve-operation method in Republic of Korea does not take into account energy-system conditions, such as the intermittency of the VRE. Therefore, this paper presents an analysis of the impact of changes in reserve-operation methods on the electricity market in the future Republic of Korean power system, with the increased levels of VRE that are currently envisioned. Specifically, three reserve-operation methods, including Korea’s current reserve-power-operation standards, were applied to the two power-system plans announced by the Korean government to analyze the annual generator operation and costs. The analysis results show that securing reserves proportional to the VRE would exert negative effects, such as increased power-generation costs and the curtailment of nuclear and VRE generation. These results can contribute to the estimation of operational reserves needed for high levels of VRE and to the design of new the Korean reserve market, to be introduced in 2025.
Increasing levels of solar PV can challenge system operations and may require novel methods to operate the power system reliably and efficiently. Power system operating plans generally use deterministic forecasts, in which the variable energy resources are represented by the expected value for each interval of the decision horizon. Probabilistic forecasts are relatively new but have the potential to address the shortfalls of deterministic forecasts. However, understanding how best to use such forecasts is still a key gap in industry and was the focus of this project. The project had three workstreams. In a forecasting workstream, improvements were made to baseline probabilistic forecasts using a number of new approaches such as machine learning methods and improved input data. In a design workstream, advanced simulation tools used these forecasts to investigate newly proposed reserve determination methods. Lastly, in a demonstration workstream a scheduling management platform (SMP) was developed to leverage probabilistic forecasts in a modular and customizable manner. In order to study the benefits that could be accrued, the project team collaborated with three utility partners (Duke Energy, Southern Company and Hawaiian Electric) to deliver improved probabilistic forecasts for each region and to model each region in case studies using advanced production cost modeling tools. Different methods to determine operating reserve requirements from probabilistic forecasts were developed, simulated, and tested across each region. The benefits of using these newly proposed methods varied by utility, but, in general, using probabilistic forecasts as well as historical data to set the reserve requirements seems to improve reliability related results, with less risk of reserve or supply shortfalls. The cost implications were not always straightforward; in some cases the new methods could show a reduction in expected operating costs, but often the increase in reserves associated with better risk mitigation using probabilistic forecasts could result in an increase in operating costs in the simulations. The SMP tool was developed to process probabilistic forecasts from their initial receipt through to scheduling decisions. This open-source tool consists of several modules for scenario development, reserve requirements calculation, and visualization. The SMP tool was demonstrated to a wide range of operators and stakeholders at all three utilities and further improved based on their feedback. The tool will be available on www.epri.com/optsun. The proposed probabilistic information-based reserve determination approaches have the potential to be implemented by different regions to ensure an economic and reliable power system operation on power systems integrating increasing levels of variable renewable resources. The innovative yet practical methods developed in this project demonstrated tangible benefits from using probabilistic forecasts beyond just study-based assessments to include three unique balancing areas. The demonstrated benefits across the multiple utility environments, are expected to provide system operators in all regions the confidence required and a platform to adopt the new forecasting and operating methods.
The Bishop Paiute Tribe is committed to energy efficiency, renewable energy, and environmental protection and has a vision to install solar energy systems on all buildings on the Reservation where technically feasible. Through completion of the Bishop Paiute Tribe Residential Solar Program – Phase 4, Bishop Paiute Tribe continued its successful model partnering with non-profit solar installer GRID Alternatives to advance its vision and build energy self-sufficiency on the Bishop Paiute Reservation. The Bishop Paiute Tribe Residential Solar Program – Phase IV deployed 67 kW-AC of new clean, renewable energy through grid-tied, net-metered rooftop solar electric systems installed on a total of 20 (one more than the planned 19) existing owner-occupied, single-family homes for low-income families on the Reservation. This represents nearly 14% of the Reservation’s total “unsolarized” homes. These systems were provided at no cost to the homeowners, who will also receive energy efficiency education to further reduce energy consumption and lower electric bills. GRID led a solar installation for three (3) of the homes where Tribal/community members, were given an opportunity in participating in on-the-roof trainings to gain new skills while installing solar for their low-income community members. Subcontractors through GRID Sub Contractor Partnership Program (GRID SPP) led solar installations for seventeen (17) of the homes. Each installation provided paid employment for a solar trainee trainees hired by the SPP subcontractors as entry level solar installers. It is estimated that the installed 67 kW-AC of solar will produce at least 120,000 kWh/year, displacing at least 30-75% of the 20 homes’ total electricity use for a combined system lifetime electricity cost savings for the low-income homeowners of about $\$$500,000. It is further estimated that the installed renewable energy systems installed will prevent greenhouse gases by about 1,000 tons, equivalent to planting approximately 25,000 trees. Following the successful completed installations, it is expected that the Reservation and surrounding communities will benefit from improved air quality via reduced wood stove use for heating. Cumulatively with other initiatives, the project will result in nearly 40% of the Reservation’s solarizable homes being solarized. Overall, the triple impact of the phase 4 of the Bishop Paiute Tribe Residential Solar Program – Phase 4 is: 1) affordable energy for low-income families; 2) on-site clean energy production, 3) hands on training and paid solar installation work for local tribal/community workers. These impacts will support and grow the Tribe’s energy, economic, environmental, and social self-sufficiency and sovereignty amongst the neediest on the Reservation.
Adoption of paired solar-plus-storage systems has accelerated in recent years, driven by both the demand for backup power and a desire to manage utility bills. Tradeoffs between those two uses can arise through the reserve setting on the battery storage system, which serves to maintain a minimum state of charge in case of a power interruption. Our paper applies an economic framework to evaluate this tradeoff in terms of changes in bill savings and customer reliability value across reserve levels, considering how those tradeoffs depend on the underlying electricity rate structure and levels. The analysis is based on a representative set of load profiles, solar profiles, tariff designs, and stochastic power interruption events across ten different regions in the United States. We find that the opportunity cost of holding storage capacity in reserve, in terms of foregone bill reductions, outweighs any gains in reliability value from mitigated power interruptions in the majority of customer situations. Higher storage reserve levels increase total customer value only in specific circumstances, such as for customers with inferior reliability (10x average interruptions), with a very high value of lost load ($50/kWh), and with tariff or interconnection rules that disallow grid charging. However, even this result is dampened when considering tariff designs with higher price differentials that increase the opportunity cost of holding storage in reserve (e.g. import/export or time-of-use rates). Allowing grid charging in tariffs essentially eliminates the necessity to hold any storage in reserve in all sensitivity cases explored.