or the utility grid. The diesel engine generator can also be a renewable source of electricity when the engine is fed with biofuels. The schematic diagram of a hybrid‐connected PV plant is shown in Figure 1.7. The plant can provide electricity for both DC and AC loads [5].5 Grid Energy StorageFigure 1.8 shows the schematic diagram of a grid energy storage PV power plant. The grid energy storage can be considered as a special model of hybrid‐connected plant. This type of power plant is used for countries where the guaranteed purchase tariff for electricity varies in peak, low, and medium load conditions. In the time periods when the guaranteed electricity purchase tariff is lower, the energy produced by the power plant is stored in batteries. When the tariff rate is higher at peak load conditions, the stored energy is injected into the grid to increase the annual revenue of the power plant.Figure 1.7 Schematic diagram of a hybrid‐connected PV plant.Source: Modified from Kalogirou [5].Figure 1.8 Schematic diagram of a grid energy storage PV plant.
PV power plants can be installed almost anywhere. Based on the location of installation, the PV plants are divided into three main categories: residential, industrial and commercial, and utility‐scale. Figure 1.9 shows the types of PV plants based on their installation location. A residential PV system provides power to a home and/or to the grid. A commercial and industrial PV plant supply power to a corporate organization or an industrial plant. A utility‐scale PV plant provides power to the grid.
Homeowners can benefit from installing a PV system in their property almost everywhere. Depending on the government policies, there are two configurations for operating a residential PV system. In the first configuration, the residential PV system supplies the home energy, and the surplus energy is injected to the grid to offset the electricity bill through net metering. In the second configuration, the produced energy by the residential PV system is totally injected to the grid by a separate meter than the home electricity meter. The price of energy sold to the grid is paid to the home owner. Note that a utility‐scale solar facility generates solar power and feeds it into the grid, i.e. supplying a utility with energy, whereas the commercial and industrial projects supply power to corporate organizations and industrial plants.
Figure 1.9 Different types of PV plants based on their installation location.
Source: Goodrich et al. [6]. Public Domain.
Figure 1.10 Classification of power plants in terms of their mounted places.
The commercial, industrial, and utility‐scale PV plants are classified into five categories as shown in Figure 1.10, namely, ground‐mounted, floating, building‐integrated, rooftop mounted, and agrivoltaics. A ground‐mounted PV plant is installed on a land, whereas a floating PV plant is installed on a water lake. In a building‐integrated PV plant, solar panels are placed in the facade of a building. An agrivoltaics or agrophotovoltaics plant is installed in a greenhouse or agricultural farm and a rooftop mounted PV plant is installed on roof of a house, building, or factory [7].
Figure 1.11 Classification of power plants in terms of size.
Source: Rakhshani et al. [8]. Licensed Under CC BY 4.0.
Figure 1.11 shows that the PV power plants can be categorized into four groups based on their output power: small‐scale, medium‐size, large‐scale, and very LS‐PVPPs [8]. The large‐scale PV plants are known as solar farms and the very large‐scale PV plants are commonly known as solar parks. In addition to a distribution substation, the large‐scale and very‐large‐scale PV plants usually have one or more transmission or sub‐transmission substations.
1.3 Global PV Power Plants
In the last two decades, significant numbers of PV power plants have been installed worldwide. The cumulative installed capacity of PV plants by the end of 2020 has reached about 751 GW. There are few reasons for investing in solar plants. The most important ones are:
1 The economic incentives that some countries grant the investors by providing subsidies or purchasing PV power at high rates. Such incentives are included in the guaranteed electricity purchase tariff and are defined as a refund for the installed PV plants.
2 The improvement in the efficiency of PV modules in recent years. Figure 1.12 shows the curves of the efficiency improvement of PV modules for monocrystals and polycrystals from 2010 to 2020 [9].
3 The reduction in the costs of inverters and PV modules in recent years. The number of manufacturers of inverters and PV modules has significantly increased over the past few years. Due to the competitive market, the price of solar inverters and PV modules has been declining to date. Reducing the costs of equipment has led to generating more economical energy from PV plants. Figures 1.13 and 1.14 show the cost trends of solar inverters and PV modules from 2010 to 2020, respectively [9].Figure 1.12 Average module efficiency, 2010–2020.Source: Modified from Feldman et al. [9].Figure 1.13 Utility‐scale and commercial inverter prices, 2010–2020.Source: Modified from Feldman et al. [9].
4 Producing electric power from the sun is viable in most places and it helps to reduce the earth's greenhouse gases. Following the Paris Climate Accords, adopted in December 2015, an effective way taken by most countries to reduce the greenhouse gases has been to construct more numbers of PV plants. The Paris Agreement aims to achieve a neutral climate without greenhouse gas emissions by 2050.Figure 1.14 PV modules prices, 2015–2020.Source: Modified from Feldman et al. [9].
1.4 Perspective of PV Power Plants
To predict the growth of large‐scale PV plants, the advantages and disadvantages of PV plants should be identified. A more realistic vision about the future of PV plants can be imagined by considering the fundamental crises of global energy consumption and the leading policies for its resolution. In this section, some of the advantages and disadvantages of the grid‐connected PV plants are discussed.
The most important advantages of the grid‐connected PV plants are:
Worldwide
