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[en] United States congressional members rolled out their "Green New Deal" in 2019 that calls for a rapid shift to carbon-free energy. As laid out by Rep. Ocasio-Cortez (D-NY) and Senator Markey (D-MA), the Deal calls for some drastic measures to cut carbon emissions across the economy, from electricity generation to transportation to agriculture to building efficiencies.
[en] The state of Rio Grande do Norte is a leader in wind power generation in the country with more than 150 wind farms in operation and 4 GW of installed capacity. Although the wind energy industry continues to grow, there are still very few papers that analyze wind behavior at heights above 80 m, which is typically the height of a wind turbine rotor. In this paper, a 95 m wind behavior analysis was carried out in two wind farms in the city of Parazinho-RN on monthly, seasonal and hourly scale, with the goal of identifying which periods of 2017 were more favorable for wind power production in the region. The wind speed and direction data used in this study were collected by a Thies First Class high precision cup anemometer and a Thies Compact wind direction indicator, corresponding to the hourly average of the measurements performed every second and integrated in intervals of 10 minutes in the period from January 1 to December 31, 2017. According with the results presented in this paper, it was verified that spring is the season of 2017 that presents the highest average monthly wind speeds, with maximum peak in the month of September, while lower speeds vary during the March-April-May quarter. The diurnal period between 10:00 am and 5:00 pm local time is the one with the most frequently wind speed ≥ 10 m.s-1. Wind direction varies from east to south, with predominance of east and southeast directions, in about 80% of the time. During the quarters that correspond to summer and fall, Weibull distributions are more concentrated around 6.5 and 7 m.s-1, indicating that in this period of the year there is a greater probability of occurrence of lower average speeds, implying in lower productivity for wind energy. The opposite is observed in winter and spring, with the exception of June, where the distributions are more concentrated around speeds ≥ 8 m.s-1 and there is a higher probability of higher average speeds to occur, showing that this was the best period of the year 2017 for wind power generation. (author)
[en] This study focuses on investigating possible changes in hydrometeorological behavior on important Brazilian river basins for power generation purposes. Thereby, this research analyzes the historical averages and observed trends regarding rainfall and streamflow and their impact on the hydrological regime. Ten river basins were selected for the assessment of alterations in the precipitation and streamflow series throughout descriptive measures and statistical significance tests (Mann-Kendall and Sen’s slope). These data are available over different time spans, but most of the records include information from 1961 to 2006. As long as these river basins are subjected to different climate types, their corresponding rainfall and streamflow patterns vary accordingly the basin location in the country, in addition to the season. Most of the country has a predominantly tropical climate, with a wet period concentrated between October and March and a dry period between April and September. Some exceptions are the Northeastern region, where the climate is semi-arid, besides the Southern region, where there is abundant precipitation throughout the year. According to the obtained results, it could be noted that the streamflow response to precipitation is faster in the smaller river basins, what can be due especially to the water travel time. It was found that Belo Monte basin, in Northern Brazil, presents a statistically significant reduction in the annual rainfall. Furthermore, a significant decrease in the annual streamflow was also identified in Xingó and Sobradinho basins, in the Northeastern region. In contrast, Itaipu basin, located in Southern Brazil, showed increasing statistically significant trends in annual rainfall and streamflow during the second half of the twentieth century. Relevant decreasing trends were also identified in the minimum streamflows of the Brazilian Northern and Northeastern basins and increasing ones in the maximum streamflows in the Southern region basins. The results obtained in this work will support the assessment of the impact of rainfall and streamflow future scenarios in regulating capacity of the hydroelectric power plant reservoirs.
[en] Need for markets for long term contracts for all generation units: • REN support and long term contracts expected to be maintained in order to reach long term objectives; • This, in turn calls for long term arrangements for all plants in order to guarantee the necessary level of capacity retention and of new capacity.
[en] Key messages: 1. Achieving 1.5°C requires an unprecedented transformation of the electricity sector; • On average, 3x nuclear and 30x solar/wind (or, deployment 50% and 650% above historical peaks). 2. Accelerating and scaling up nuclear power for 1.5°C appears to be feasible in terms of economic, resource and industrial capacity
[en] As much wind power is connected to the power system, the accommodation of the wind power in the power grids becomes a huge challenge to the operation model of China’s power system. Releasing and improving the flexibility of the power system will be necessary and important to enable the accommodation of power generated with renewable energy sources, which is connected to the power grids on a large scale and accounts for a high proportion. The paper, with North Hebei as an example, discusses the relationship between the demand for the flexibility of thermal power units and the accommodation of wind power. This paper further analyzes the demand for peak load regulation in North Hebei at both the present and the future as well as the characteristics of power sources in the power grids of North Hebei and the technical potential of power generation. It also compares the quantity of curtailed power before and after the flexibility-oriented transformation of thermal power units in North Hebei and calculates the minimum technical output of thermal power under different levels of accommodation of wind power. The research shows that the peak load regulating resources in the power grids of North Hebei boast huge potential, but in the long term, to achieve the objective of a 10% curtailment rate of power generated with renewable energy sources, the minimum technical output of condensing units must be lower than the internationally advanced level of 25%. So, it is difficult to fulfill the said objective solely relying on the strengthened transformation of generating units. To reach the level of 5% curtailment rate of power generated with renewable energy sources, the minimum technical output must achieve breakthrough improvement, which requires continuous technological innovation and power flexibility in close coordination.
[en] Engineering specific issues: • Equipment Specifications • Pre-installation Inspections and post installation inspections; • Non-conformances; • Foreign Material Exclusion; • Decision Making on critical path; • Returning Systems to service; • Making plan changes and the regulator.
[en] Examples of partnerships from IRENA: - Global Geothermal Alliance; - SIDS Lighthouses Initiative; - Open Solar Contracts; - Long-Term Energy Scenarios for the Clean Energy Transition; - Coalition for Action.