Presently, the world is undergoing exciting haste to install photovoltaic (PV) systems in industry, residential/commercial buildings, transportation, deserts, street lights, and many other applications. Solar photovoltaic energy systems are clean and reliable energy sources that are unlimited, unlike their fossil fuel counterparts. The energy market is rapidly growing globally with newly and cumulative installed capacities of about 37.6 GW and 139.6 GW, accounting for 53% and 55%, respectively, in 2017, making it one of the fastest-growing industries. The cumulative photovoltaic installations are projected to have reached 600 GW worldwide and are projected to reach 4500 GW by 2050 because of the strategies and policies of many countries. In 2021, more than three-quarters of the developed countries are now home to one solar installation. This article evaluates a critical and extensive review of the contributions of solar photovoltaic systems to national development. The approach follows all steps, starting with capturing photovoltaics on the Earth’s surface, then price reduction, load management, and socioeconomic impact of solar photovoltaic systems. From the study, it is found that the policies and strategies adopted by the leading countries, such as tax credits, capital subsidies, net-metering, VAT reduction, feed-in tariffs (FiTs), and renewable portfolio standards (RPS), have significantly helped in more installations. Additionally, the significant drop in photovoltaic module prices from 4731 $/W in 2010 to 883 $/W in 2020 has boosted the move for more installations. Based on the findings, approximately 10 million permanent employments would be put in place by advancing solar power across the globe annually.

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Contributions of Solar Photovoltaic Systems to Environmental and Socioeconomic Aspects of National Development—A Review

An information gap decision theory-based decision-making model for complementary operation of hydro-wind-solar system considering wind and solar output uncertainties

Feasibility analysis of achieving net-zero emissions in China's power sector before 2050 based on ideal available pathways

Low-head vertical axial-flow pump as turbine (PAT) devices play a vital part in the development of clean energy for hydropower in plain areas. The traditional method of evaluating the flow loss in hydraulic machinery is calculated by the pressure drop method, the limitation of which is that the location of the occurrence of large losses cannot be accurately determined. In this paper, entropy production theory is introduced to evaluate the irreversible losses in the axial-flow PAT from the perspective of the second law of thermodynamics. A three-dimensional model of the axial-flow PAT is established and solved numerically using the Reynolds time-averaged equation, and the turbulence model is adopted as Shear Stress Transport–Curvature Correction (SST-CC) model. The validity of the entropy production theory to evaluate the energy loss distribution of the axial-flow PAT is illustrated by comparing the flow loss calculated by the pressure drop and the entropy production theory, respectively. The entropy production by turbulent dissipative dominates the total entropy production in the whole flow conduit, and the turbulent dissipative entropy accounts for the smallest percentage of the whole conduit entropy production at the optimal working condition Qbep, which is 51%. The impeller and the dustpan-shaped conduit are the essential sources of hydraulic loss in the entire flow conduit of the axial-flow PAT, and most of the energy loss of the impeller occurs at the blade leading edge, the trailing edge, and the flow separation zone near the suction surface. The energy loss of the dustpan-shaped conduit results from the high-speed flow from the impeller outlet to dustpan-shaped conduit to form a vortex, backflow and other chaotic flow patterns. Flow impact, flow separation, vortex and backflow are the main causes of high entropy production and energy loss.

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Numerical Study for Flow Loss Characteristic of an Axial-Flow Pump as Turbine via Entropy Production Analysis

Contribution of complementary operation in adapting to climate change impacts on a large-scale wind–solar–hydro system: A case study in the Yalong River Basin, China

Impacts, challenges and suggestions of the electricity market for hydro-dominated power systems in China

Long-term stochastic model predictive control and efficiency assessment for hydro-wind-solar renewable energy supply system

Renewable energies such as hydro, wind, and solar power, are susceptible to the impacts of climate change. Energy Impact Assessment models under climate change are useful tools for understanding these impacts, but still face some challenges, such as the limited spatial resolution, the lack of utilization of the latest climate models, the inadequate analysis of uncertainties and extreme behaviors, and having not enough capability in simulating the coordinated operation of different power sources. To improve the situation, this study utilizes Random Forest Regression and its derivative Quantile Regression Forest to downscale the CMIP6 General Circulation Models for projecting the means and quantiles of the renewable energy resources for each individual power station under seven combined pathways of Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs). Based on the projected results, a coordinated operation strategy is established to quantify the impacts of climate change on the regional hydro-wind-solar energy supply system. The assessment reveals: (1) changes of hydro-meteorological variables will present spatially and seasonal inhomogeneous; (2) at the end of the century, the projected increased level of electricity supply will be the highest under the SSP5-RCP8.5 and the increment will be 8.680 TWh; (3) the extreme lack electricity supply will occur under the SSP3-RCP7.0 for the period 2041–2060 and the twenty-year average value will be reduced by 16.83 TWh relative to the historical period reference period. • A novel assessment model for climate change impacts on the hydro-wind-solar energy supply system. • Perfect-prognosis statistical downscaling using the latest CMIP6 General Circulation Models. • Projection for means and quantiles of the renewable energy resources. • New analysis of future electricity supply with regard to climate change. 

Ze-bin Jia

Papers

Impacts, challenges and suggestions of the electricity market for hydro-dominated power systems in China

Long-term stochastic model predictive control and efficiency assessment for hydro-wind-solar renewable energy supply system

Assessment of climate change impacts on the hydro-wind-solar energy supply system

Optimum day-ahead clearing for high proportion hydropower market considering complex hydraulic connection