In order to mitigate energy crisis and to meet carbon-emission reduction targets, the use of electrical energy produced by solar photovoltaic (PV) is inevitable. To meet the global increasing energy demand, PV power capacity will be expanded ranging from large-scale (from ten to several hundred MWs) PV farms at high and medium voltage level to kilowatt residential PV systems at low voltage level. It is expected that the PV penetration will increase in po. In order to mitigate energy crisis and to meet carbon-emission reduction targets, the use of electrical energy produced by solar photovoltaic (PV) is inevitable. To meet the global increasing energy demand, PV power capacity will be expanded ranging from large-scale (from ten to several hundred MWs) PV farms at high and medium voltage level to kilowatt residential PV systems at low voltage level. It is expected that the PV penetration will increase in power systems with the retirement of traditional carbon-emission emitting power plants. Solar energy is diurnal in nature and in practice, it is highly uncertain due to various perturbation effects. With the recent technological advancements and rapid cost reductions in electrical energy storage (EES), EES could be deployed to enhance the system's performance and stability. This paper presents a comprehensive review on the emerging high penetration of PV with an overview of EES for PV systems. The crucial element, the building block of solar panel and the solar cell are reviewed. The emerging cell technologies are presented. A study of solar power forecasting techniques, an important tool for the successful operation and planning of PV and EES is included. A selection of EES is presented and studied for PV system purposes. Future research and areas for improvements in recent works and related areas are identified.••••Photovoltaic (PV) generation capacity and electrical energy storage (EES) for worldwide and several countries are studied.••Critical challenges with solar cell technologies, solar forecasting methods and PV-EES system operation are reviewed.••The EES requirements and a selection of EES for PV system are provided.••Social and technological implications to the power sector and consumers with high penetration of PV and EES are discussed.PhotovoltaicElectrical energy storageSolar cellPV forecastingRenewable energy has been used by humanity for several millennia. In fact, hydro, wind, solar and biofuel power were the only available energy sources during the ancient times. The Industrial Revolution in the 18th century has opened a new era of energy production and consumption methods. This has a tremendous positive effect to the development and advancement for civilization. However, the significant environmental adverse impacts are noticeable in the last several decades. Carbon dioxide has been emitted from burning fossil fuels, i.e. coal, oil and gas. The consequences of generating fossil fuel based power are global warming due to carbon emission and a significant increase in the environmental pollution levels. In recent decades, governments from several countries realized the severe issues. There is a need to reassess the ways in which energy is generated and consumed in order to minimize pollution from emission, planetary global warming rate, and mitigate the nuclear accidents risks.The renewable industry has experienced a boom in the recent years. There is an increase in the penetration of renewable energy in the energy mix of developing and developed countries. Such increase can bring the grid to economic and technical challenges due to the connection of intermittent renewable energy sources. There is a motivation in the development of impro. Several countries are aiming to maximize their solar energy portfolios. Greenpeace stated that it is possible to become 100% renewable by 2050 and therefore experiencing a very sharp increase in installations. To provide a glance of the PV capacity significance in a power system, the term PV penetration is used. The PV penetration level is normally used to conduct various sensitivity analysis for power system with PV generator. This is the amount of power generated by PV with respect to the total power generated in a power system. The definition of PV penetration level has been discussed in, and is calculated with Eq. (1). It is worth mentioning that other definitions of penetration level for distributed generators were also defined, such as in where the peak load of the system is used as the denominator.(1)PVPenetration(%)=SumofPVgeneration(MW)Sumofsystemge. Fig. 1 presents the trends for global power capacity of solar PV systems from different literatures and case scenarios. Greenpeace has provided a forecast of global PV penetration under two scenarios, namely the “revolution scenario” and “reference scenario”. It is shown that there is a sharp linear growth in solar power capacity with respect to time.
