Analysis of System Value Evolution Trends of Energy Storage in Decarbonization Process

With the continuous expansion of the scale of renewable energy installation,the demand for energy storage has increased significantly.However,there are significant differences in the value of energy storage in different scenarios,and the phenomenon of diminishing marginal benefits of energy storage is becoming more apparent.Therefore,themulti-dimensional value evolution trend of energy storage has become a key issue.This study selects indicators from three dimensions of energy storage:low-carbon emission reduction,smoothing wind and solar power fluctuations,and saving generation costs,quantifying the economic,environmental,and technical values of energy storage.This forms a quantitative evaluation system for energy storage value.By comparing the calculated system values under different energy storage capacities,the marginal value evolution trend of energy storage is obtained.Meanwhile,considering factors such as the utilization rate of renewable energy,the change in energy storage value under different scenarios is analyzed.The results show that the value of long-duration energy storage is significantly affected by the energy storage capacity.Specifically,when the charge-discharge efficiency of longduration energy storage reaches 0.6 or above,the system value increases significantly.Additionally,appropriately reducing the cost of energy storage capacity also helps to improve its system value.

Determination of Breeding Target and Marginal Benefit Calculation of New Type of Shuxuan Beef Cattle

[Objectives]To make targeted breeding of new type of Shuxuan beef cattle,study and determine the breeding target traits of new type of Shuxuan beef cattle.[Methods]The difference method was used to calculate the marginal benefit of each target trait,and the economic weight of the corresponding breeding target trait was obtained.[Results]The marginal benefits of weaning weight,fattening daily gain,18-month weight,carcass quality,dressing percentage,pure meat percentage,age at first calving,calving interval and stay group time were 35.86,13.76,13.05,421.96,375.55,22.58,-4.45,-27.53,and 1555.24,respectively.The relative economic weight ratio of growth traits,carcass traits,and reproductive traits was close to 4∶1∶5.Through marginal benefit analysis,the economic benefits obtained by improving carcass quality,dressing percentage and stay group time were significantly higher than other traits.[Conclusions]It is expected to provide a theoretic basis for establishing the target trait selection indicators for the new type of Shuxuan beef cattle.

Intensive Versus Extensive Events?Insights from Cumulative Flood-Induced Mortality Over the Globe,1976–2016

More attention has been paid to the cost of intensive but sporadic floods than the cost of extensive but frequent events.To examine the impacts of intensive versus extensive events,we investigated the loss structure of global flood-induced mortality by using the cumulative loss ratio,marginal benefit chart,and cumulative loss plot.Drawing on the flood-induced mortality data for four decades(1976–2016)from the international disaster database EM-DAT,we defined the levels of flood loss according to the frequency of flood-induced deaths,and calculated the cumulative mortality and the marginal benefits of flood loss prevention practices at different levels.Our analysis showed that for the world’s leading 30 countries with large flood-induced mortality and different levels of development:(1)70%of them have the cumulative deaths from extensive floods exceeding half of those caused by intensive floods in the study’s four data decades;and(2)80%of them tend to gain less marginal benefit with increasing levels of flood prevention,with their marginal benefits peaking at loss prevention levels of 2-year or 5-year flood-induced mortality.These results indicate that,in the long run,the cumulative deaths of extensive floods are comparable to that of intensive events,and prevention of loss from extensive events can be an efficient way to reduce the total loss.For flood risk management under conditions of climate change,extensive loss events deserve more consideration.