With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;"...With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based baseload</span><span style="font-family:""> <span style="font-family:Verdana;">generation is forced to decline</span><span style="font-family:Verdana;">, thus making room for more and more generation based on renewable and other carbon-free energy sources. This paper deals with a number of controversial issues and open questions concerning </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">growing penetration of renewable energy sources into power generation systems, often without due care of the impacts of variable as compared to conventional generation on </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">reliability of electricity supply. Particular attention is paid to baseload generation, power market design, system operation under extreme weather conditions, energy storage, back-up</span><span style="font-family:Verdana;">,</span><span style="font-family:""><span style="font-family:Verdana;"> and reserve power, as well as to the role of mechanical inertia an</span><span style="font-family:Verdana;">d reliability of on-site fuel supply, demonstrated on an example of coal </span><span style="font-family:Verdana;">excavation and delivery to a power plant.展开更多
For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain...For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of U.S. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to U.S.electricity grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. Statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. Since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.展开更多
Several factors have led to the decline of electricity generation from coal over the past decade, and projections forecast high rates of growth for wind and solar technologies in coming years. This analysis uses hourl...Several factors have led to the decline of electricity generation from coal over the past decade, and projections forecast high rates of growth for wind and solar technologies in coming years. This analysis uses hourly generation data from large coal-fired power stations to determine how operations have been modified in recent years and describes the implications of these changes for plant equipment and unit reliability. The data shows increasing variability in intraday generation output that affects nearly all of the units in the sample, but the magnitude of increase varies widely among plants. Outage patterns were examined as was the relationship between renewable energy growth in a region and the changes in coal plant operations. Aggregate direct and indirect costs associated with running coal plants as load-following units have not yet been quantified in large-scale studies on a sector-wide basis, largely due to differences in how specific equipment responds to output fluctuations. Due to findings from the hourly generation data analysis and the high degree of potential impact on coal plant equipment, the study suggests the development of a new modeling tool that will represent the costs of running coal-fired power plants at lower capacity factors.展开更多
文摘With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based baseload</span><span style="font-family:""> <span style="font-family:Verdana;">generation is forced to decline</span><span style="font-family:Verdana;">, thus making room for more and more generation based on renewable and other carbon-free energy sources. This paper deals with a number of controversial issues and open questions concerning </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">growing penetration of renewable energy sources into power generation systems, often without due care of the impacts of variable as compared to conventional generation on </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">reliability of electricity supply. Particular attention is paid to baseload generation, power market design, system operation under extreme weather conditions, energy storage, back-up</span><span style="font-family:Verdana;">,</span><span style="font-family:""><span style="font-family:Verdana;"> and reserve power, as well as to the role of mechanical inertia an</span><span style="font-family:Verdana;">d reliability of on-site fuel supply, demonstrated on an example of coal </span><span style="font-family:Verdana;">excavation and delivery to a power plant.
文摘For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of U.S. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to U.S.electricity grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. Statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. Since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.
文摘Several factors have led to the decline of electricity generation from coal over the past decade, and projections forecast high rates of growth for wind and solar technologies in coming years. This analysis uses hourly generation data from large coal-fired power stations to determine how operations have been modified in recent years and describes the implications of these changes for plant equipment and unit reliability. The data shows increasing variability in intraday generation output that affects nearly all of the units in the sample, but the magnitude of increase varies widely among plants. Outage patterns were examined as was the relationship between renewable energy growth in a region and the changes in coal plant operations. Aggregate direct and indirect costs associated with running coal plants as load-following units have not yet been quantified in large-scale studies on a sector-wide basis, largely due to differences in how specific equipment responds to output fluctuations. Due to findings from the hourly generation data analysis and the high degree of potential impact on coal plant equipment, the study suggests the development of a new modeling tool that will represent the costs of running coal-fired power plants at lower capacity factors.
