With the increasing grid penetration levels of wind power, there is an increasing need to study both the power control systems and the regulatory aspects associated with frequency control capabilities of wind power pl...
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With the increasing grid penetration levels of wind power, there is a large need for the energy reserves for grid support during under-frequency conditions. Such energy reserves are created by operating the wind farm ...
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There is a growing importance for improving renewable energy policies especially in the United States to achieve a goal of 20% or more of nation's electricity from wind energy by 2030. Governments at various local...
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ISBN:
(纸本)9781479939350
There is a growing importance for improving renewable energy policies especially in the United States to achieve a goal of 20% or more of nation's electricity from wind energy by 2030. Governments at various local, state and federal levels often revise the policy design and implementation to encourage renewable electricity generation. This paper illustrates some of the renewable energy policies (especially wind) of Texas at state level and United States at federal level and also discusses issues within those policies. Special focus is put on the following topics: Renewable portfolio standards, Production Tax credits, Feed-in tariffs and Net-metering.
With the increasing grid penetration levels of wind power, there is an increasing need to study both the power control systems and the regulatory aspects associated with frequency control capabilities of wind power pl...
详细信息
ISBN:
(纸本)9781467344456
With the increasing grid penetration levels of wind power, there is an increasing need to study both the power control systems and the regulatory aspects associated with frequency control capabilities of wind power plants at various levels (turbine, wind farm and power system levels). This is especially very important in the United States with a goal of achieving 20% nation's electricity from wind energy by 2030. This paper provides observations and challenges identified with wind energy integration with respect to active power control strategies used in implementing frequency regulation at various levels. This paper also discusses the current and future aspects of market regulation of frequency responsive services offered by converter based variable generation technologies and the need for an appropriate utility market structure in order to provide settlements for these capabilities.
Background: Decades of steady improvements in life expectancy in Europe slowed down from around 2011, well before the COVID-19 pandemic, for reasons which remain disputed. We aimed to assess how changes in risk factor...
Background: Decades of steady improvements in life expectancy in Europe slowed down from around 2011, well before the COVID-19 pandemic, for reasons which remain disputed. We aimed to assess how changes in risk factors and cause-specific death rates in different European countries related to changes in life expectancy in those countries before and during the COVID-19 pandemic. Methods: We used data and methods from the Global Burden of Diseases, Injuries, and Risk Factors Study 2021 to compare changes in life expectancy at birth, causes of death, and population exposure to risk factors in 16 European Economic Area countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, and Sweden) and the four UK nations (England, Northern Ireland, Scotland, and Wales) for three time periods: 1990–2011, 2011–19, and 2019–21. Changes in life expectancy and causes of death were estimated with an established life expectancy cause-specific decomposition method, and compared with summary exposure values of risk factors for the major causes of death influencing life expectancy. Findings: All countries showed mean annual improvements in life expectancy in both 1990–2011 (overall mean 0·23 years [95% uncertainty interval [UI] 0·23 to 0·24]) and 2011–19 (overall mean 0·15 years [0·13 to 0·16]). The rate of improvement was lower in 2011–19 than in 1990–2011 in all countries except for Norway, where the mean annual increase in life expectancy rose from 0·21 years (95% UI 0·20 to 0·22) in 1990–2011 to 0·23 years (0·21 to 0·26) in 2011–19 (difference of 0·03 years). In other countries, the difference in mean annual improvement between these periods ranged from –0·01 years in Iceland (0·19 years [95% UI 0·16 to 0·21] vs 0·18 years [0·09 to 0·26]), to –0·18 years in England (0·25 years [0·24 to 0·25] vs 0·07 years [0·06 to 0·08]). In 2019–21, there was an overall decrease in mean annual life expectancy a
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