Solar has been used to generate power for several centuries, with magnificent discoveries and inventions such as the photovoltaic effect in 1836, which led to the invention of photovoltaic solar panel. Since the discovery of photovoltaic effect and the invention of the solar panels, much progress has been made, with sophisticated systems such as the solar park being used to generate power in large-scale that is supplied to the electricity grid. Solar parks, also known as photovoltaic power stations, have increased in use and popularity in the modern world due to the numerous benefits and few disadvantages associated with the form of large-scale power generation.
The difference between Photovoltaic Power Stations and decentralized solar power applications such as the Building-Mounted Systems is that the former supplies power at utility level while the latter supply to the local user or users. However, in some parts of the United States and Canada, small-scale photovoltaic power producers including Building Mounted Power systems supply power at the utility level. Increasing growth of the PV power stations has increased over the years, whereby integration of photoelectric power on the grid has increased popularity of the technology.
Figure 1: A Photovoltaic Power Station (Lave 2013)
Figure 2: Example of a Building-Mounted solar power system, in Barcelona, Spain (Sun et al. 2014 ).
A big number of photovoltaic solar power stations are PV systems mounted on the ground, which are known as free-field solar power plants. The ground mounted PV systems can be fixed tilt, or can utilize single or dual axis solar tracker. According to Chu et al (2013) although tracking enhances performance, the technique raises the cost of installing and maintaining the system. Hirth (2014) also notes that the photovoltaic solar power stations are composed of several components, which include photovoltaic arrays, solar inverter, and step up transformer.
Singh (2013) further explains that photovoltaic arrays convert sunlight to electricity in Direct Current form, the inverter in turn converts the generated DC to AC, which is connected to the utility grid via a high voltage transformer. Typically, a three-phased step up transformer with over ten kilo Volts is used.
Photovoltaic technology is a technique used to produce electric power directly from sunlight through natural electronic process in some categories of materials known as semiconductors. Solar energy frees electrons in the semiconductor, which can be induced to travel via a circuit to an electricity grid or to power devices. When the PV systems are large enough to supply huge volumes of electricity to the grid, then they are called photovoltaic solar power stations.
The process of generating electricity using photovoltaic technology starts when photons from sunlight strike, and thereby, ionizing the semiconductor material on the panel. Ionizing the semiconductor makes some of the electrons to break free of the atomic bonds. The structure of the semiconductor is designed to force electrons to flow in single direction hence creating an electric current.
According to Hosenuzzaman et al. (2015), several materials can be used as the semiconductor, which include crystalline silicon. Kurokawa (2014) indicates that crystalline silicon solar cells do not give a 100% efficiency because some light is too weak to create infrared, some of the light spectrum is also reflected, and another section generates heat instead of the expected electricity.
Figure 3: Crystalline silicon solar cell (Kurokawa 2014)
The smallest components of a photovoltaic array are the photovoltaic cells that form the modules. Arranged in a series-parallel circuit, the modules form the photovoltaic array, which in turn form the photovoltaic power plant (Kurokawa 2014).
The Solar arrays, as indicated above, are made up of a large number of photovoltaic modules that are embedded on support structures and are connected in series-parallel circuits to provide electric output to the subsystem for power conditioning. According to Budischack et al (2013) a small number of solar farms are configured in buildings hence utilize photovoltaic arrays embedded on buildings. However, Kurokawa (2014) insists that most of the photovoltaic power stations are ground-mounted; hence, use arrays that are also mounted on the ground.
2.4. Other Components of PV Power Plants
Other Components of the PV power station include inverters for converting the Direct Current from the power arrays to alternating current that is connected to the public grid. A transformer is used to step up power from the inverter to the grid.
Figure 4: Structure of a PV Solar Power Plant (Piano & Mayumi (2017))
According to Sharma & Chandel (2013), photovoltaic solar power stations performance can be approached in two ways, which are performance ratio, and capacity utilization. Performance Ratio of a photovoltaic solar power plant depends on the climatic condition, system configuration, and equipment.
A plant’s (PR) for a Period of time= Measured Energy (kWh)/ (Irradiance (kWh/m2) on the solar panel x PV module active area (m2) x PV module efficiency), and the Capacity Utilization Factor = Measured Energy (kWh)/ (365*24*installed)
Some of the factors that are critical in the comparison of CUF versus PR include
- PR takes into account the grid availability, while CUF does not.
- PR also considers the lowest level of irradiation required for electricity generation but CUF does not
- Performance Ratio considers irradiation at a specific point in time, while CUF does not
Since performance ratio takes into account environmental factors, the approach is very applicable in comparisons of different photovoltaic systems even when located in different regions (Chandel et al. 2014). Hence, the tool compares the design and the system’s ability to convert energy to electricity. Piano & Mayumi (2017) postulate that the failure of CUF to take into account essential factors such as the environment; makes the method an inefficient approach of system comparison.
Karavi et al. (2013) also conclude that PR is the best tool to measure losses between the modules’ DC output and the amount of the alternating current delivered to the grid, which are influenced by a broad range of factors such as the mismatch, conversion inefficiencies, cable voltage drop, and light absorption losses including others.
The sun, in an hour, radiates adequate energy for human consumption in a whole year; hence, mechanisms that try to harness the potential are very popular (Ellabban et al. 2014). Photovoltaic solar power generation of electricity is one such technique, which possess a myriad of benefits compared to other methods of solar energy, and the general techniques of electricity generation. However, Li et al (2013) argues that the technology is not developing at the required pace to ensure that the technique is as efficient as possible. Desideri & Champana (2014) further argues that the lag is a significant source of drawbacks, which make the technique unfavorable for large-scale projects. However, previous studies indicate that the Photovoltaic solar power stations’ power generation assimilates most of photovoltaic technique strengths. Since photovoltaic technology possesses many strengths, the solar parks are also very robust electricity generation tools (Ellabban et al. 2014).
Photovoltaic systems generate clean-green power, whereby the technique used to convert solar energy to electricity does not lead to emission of greenhouse gas; hence, making the systems friendly to the environment. Precisely, the systems assist to reduce carbon dioxide emission to the environment; hence, minimizing the ‘greenhouse effect.’ In addition, a photovoltaic system like the rest of green energy technologies, reduce or avoid the release of other harmful gases to the atmosphere that are a serious threat to the environment and public health.
According to Sueyoshi & Goto (2014), photovoltaic systems provide a reliable method for solar energy exploitation. Previous studies indicate that the existing photovoltaic systems will last for at least the next thirty years without a need for replacement. Sahu (2015) explains that not unless disaster strikes the PV systems will operate at a significant efficiency for a very long time. The autonomous way of operation is another strength of the systems.
The mode of PV systems operation unlike some other forms of green energy generation such as wind turbines does not produce disturbances and noise because of lack of moving parts except the optional tracker for adjusting the sun radiation. Therefore, PV systems in their operation do not pollute the surrounding environment. Compared to other methods of green and renewable energy generation, photovoltaic systems demand minimum maintenance.
Tyagi et al. (2013) indicates that PV systems require regular cleaning of the solar arrays surfaces and checking of cable connections. Singh (2013) also notes that most of the other technologies of generating renewable and green require mechanical efforts such as moving a turbine and hence demand a lot of maintenance due the large number of moving components.
According to Koran et al. (2014), photovoltaic systems also inherit strength of peak power generation from solar energy generation whereby maximum production is reached when demand is also at the highest point in a day. In most, energy consumption reaches maximum at midday when everybody is active, whereby in a typical urban setting, businesses such as hotels and offices are open by this time and require energy supply. Coincidentally, the high demand meets the supply also at peak; hence, shortages, which can cause blackouts, are not experienced. The attribute of the system is very helpful in peak shaving and load curve ‘smoothing’ hence minimizing chances of blackouts. Finally, the recent advances in photovoltaic technology are increasing in popularity, due various milestones in cost reduction. The reduced costs achieved have started taking effect in the market because of their application modularity, diversity and are easily installed and expanded. However, Hirth (2014) states that Photovoltaic industry are still expansive and much is required in terms of cost reduction before the technology can achieve the necessarily competitiveness in the market (Sun et al. 2014).
Solar Radiation Potential
The sun has the highest energy potential in the world and is easily accessible compared to all the other sources of renewable energy. According to a study by Tyagi et al. (2013) the yearly technical potential solar energy was more than the total yearly potential of the other renewable sources of energy by about twenty times. Sahu (2015) argues that the high global technical potential in a year for direct solar shows the room that the techniques of harnessing the category of energy source compared to the rest. In this regard, Photovoltaic solar power plants being a tool for harnessing direct solar energy possess an advantage of unlimited source of raw material. The potential of solar energy compared to others sources of renewables is higher by far. For instance, the wind’s maximal global technical potential is about 1% that of direct solar.
Reduced Carbon intensity
Compared to the fossil-based technology, Photovoltaic power plants have low carbon intensity, which shows their contribution towards a clean environment. Therefore, PVPP (Photovoltaic power plants) are a critical component of the fight against environmental that is happening globally. According to Singh (2013), reduced carbon emission is one of the factors increasing the popularity of PVPPs in the world.
Reduced Investment Cost
According to Desideri & Champana (2014) installing, exploiting, and replacing of PVPP is very simple; hence, leading to low cost of investment. Hirth (2014) indicates that installing of photovoltaic power plants is cheap because the process does not involve heavy machinery and complicated cabling. PVPP installation involves setting up of the structure for the solar arrays and few cabling from the arrays to the inverter whereby the DC out is converted to AC output. Cabling is also required from the inverter to the transformer for stepping up the AC power for connection to the grid. According to Sueyoshi & Goto (2014), the simple installation of the PVPPs requires minimum skilled labor; hence, immensely reducing the total cost of investment. Since, sunlight is the only raw material for PVPP, which is free, easily accessible, and requires no modification or transportation, the cost of exploiting the source of energy is zero. Once a power plant is set, power is produced at no cost; hence, the owner of the plant requires no extra expenses (Sun et al. 2014).
PVPP also have a long lifespan with an outstanding efficiency hence eliminating the need for replacement after a short duration. According to Singh (2013), PVPP can maintain high efficiency of about 80% for long periods of about 80 years. Karavi et al. (2013) also insists that replacing the PVPPs is very easy as they involve three components. Therefore, the plants have reduced cost of replacement, which in turn reduces the cost of investment.
The above analysis shows that unlike the rest of power generation plants such as wind PPs (Power Plants) and Hydroelectric PPs, which require heavy machinery such as turbines; hence, demand technically skilled labor for installation and replacement, PVPP demands has a low investment cost. The source of energy for the plant is the sunlight, which is free; hence, no cost of buying raw materials as is the case for fossil fuels power plants. Accessibility of the raw material is also free; hence, no costs required for transporting or for inventory, as is the case with fossil fuels power plants. Therefore, reduced or zero cost of exploitation leads to a massive reduction of the investment cost (Sun et al. 2014).
Reduced Operation and Maintenance Costs
PVPPs consist one of the lowest fixed expenditures such as Taxes, Salaries, rates, insurance, among others, and variable costs of removing waste, chemicals, maintenance, repair, chemicals, etc. PVPPs consist of few moving parts, and require a small number of employees compared to other plants, which require a huge number of high skilled labor such engineers and technicians.
According to Tyagi et al. (2013), PVPPs are fixed except for the tracking options, which have some few moving parts; hence, the plants require a small number of maintenance employees, materials, and other components of keeping them up and running. Krebs et al. (2014) insist that other methods of generating power require heavy machines to generate energy. For instance, a wind power plant requires a mill and a turbine that have a many moving parts, to produce energy. Therefore, the plant will require close monitoring by skilled personnel to identify any possible source of breakdown and perform regular maintenance. The moving parts also lead to tear and wear hence repairs have to be done regularly hence the cost of materials and chemicals is highly increased.
Reduced External Costs
There are two components of reduced costs, which are-
-Change in climate damage costs associated with carbon emissions
-Air polluting elements such as heavy and radioactive metals, which have negative impact on health, environment, and crops, damage costs.
In a study by Tyagi et al. (2013), comparing the external costs (ECs) of PVPPs and fossil fuels power plants, PVPP were found to have a low impact on human health of 0.21 EURct/kWh while that of fossil fuel power plants was found to vary from 0.28 to 2.74 EURct/kWh. The same study also indicated that fossil fuel plants have a high impact (which was found to vary from1.84 EURct/kWh up to 3.89 EURct/ kWh) on environment compared to the PVPP (0.24 EURct/kWh). Further, according to Lave (2013) the impact of power plants running on fossil fuels was found to cause a high impact on environment compared to PVPPs.
According to the study mentioned above, it is apparent that photovoltaic power plants cause low impacts on environment, human health, crops, and emit low levels of carbon compared to fossil fuel run plants. Therefore, the external costs incurred due to PVPP are by far less than by fossil fuel plants.
According to Krebs et al. (2014), some other benefits of PV power plants include security as the stations provide electricity for a considerable long time. PVPPs have long life spans ranging from 40 to 80 years of supplying energy at constant cost. Fossil fuels power plant, on the other hand, is usually affected by fuel prices in the market hence affecting the cost of power in the market. Reliability is another benefit of PVPP, where the plants assist in supplementing the other sources of energy such as wind and fossil fuels. Tyagi et al. (2013) postulates that integrating power from the PVPPs with other sources assists in increasing reliability in areas, which are prone to energy blackout. Krebs et al. (2014) indicate that disruption of power always occurs in areas that are prone to natural disasters such as hurricanes and storms. In such areas, PVPP can be used to improve reliability whenever such disasters occur. Integrating well-balanced PV power plants can also assist in avoiding or delaying local transformer substations by increasing their rated power hence improve reliability.
Since Photovoltaic Solar Power Stations inherit the general pros of solar Photovoltaic Systems due to the use of photovoltaic technique; in a similar manner, they also acquire disadvantages associated with the method. Therefore, an overview of the photovoltaic general cons is critical when analyzing the benefits of the large-scale photovoltaic disadvantages.
One of the major disadvantages of photovoltaic systems, as noted above, is that the cost of the technology is relatively high. According to Lave (2013) Compared to other sources of energy including the conventional techniques, photovoltaic technology is considerably costly. For instance, the cost of power generated by other methods of renewable and green energy such as wind and biomass is cheaper compared to that generated using photovoltaic technology. Similarly, the cost of power generated using conventional and non-renewable sources such as fossil fuels is much lower than that produced using photovoltaic technologies. Therefore, until the expected cost reduction and efficiency improvement is reached, the popularity of photovoltaic technology in the market will continue to be low. Making the technology viable economically will continue to rely on tax incentives and subsidy funding (Hirth 2014).
The type of power generated by the Photovoltaic systems is another major drawback of the technology. PV systems generate DC current, which, as explained earlier, needs inverters for connection to the power grid. Inverters are expensive devices, which play a critical role in increasing the cost of the power generation (Wang et al. 2014). In addition, to increase the reliability of PV system require the use of storage devices such as batteries, which further increase the cost of power generated by the technology (Sun et al. 2014).
According to the research also, the efficiency of generating power using the photovoltaic technology is low depending on the type of cells used. Considering the technology (thin film, poly-crystalise, and monocrystallic PV arrays) used, the efficiency of the PV system ranges from 8 percent to 20 percent.
Generally, PV systems possess a wide range of benefits and are an essential component of exploitation and utilization of renewable energy sources. However, the two primary drawbacks, which are high cost and low levels of efficiency, are critical. Therefore, further support in technological progress and finance in terms of tax incentives and subsidies is required to make the technology competitive in the market.
High Carbon Emission Compared to Other Renewable Sources of Energy
According to Krebs et al. (2014), Large-scale PV power stations are made up of many solar arrays for converting sunlight to direct current energy. Krebs et al. (2014) indicate that most of the solar arrays in use today are made of mono crystalline silicon, which has a carbon footprint, 2 728 kg/kWp of CO2 equivalent. Tyagi et al. (2013) argue that PV power plants are carbon intensive compared to the rest of renewable sources because production of silicon ingots demands a lot of power.
Singh (2013) postulates that the rest of renewable sources of energy such as wind and hydro emit little or no carbon; are more cleaner compared to PV power. For instance, wind power generation requires a mill and turbine, which do not emit carbon in the process of generating power and require little energy in production. Due to slightly high carbon emitted by PV power stations compared to other sources, the PV power has more effects on the environment; hence, have higher extra cost compared to other sources of green energy.
Increased Integration Costs
Connecting of PV into the grid includes an additional cost to the levelized cost of electricity. Integration of power to the grid includes the short-term cost of power balancing and issues related to the grid costs, and profile costs. According to Tyagi et al. (2013), the need to use, large capacitive PV power plants attract profile costs of intermittent power sources integration for balancing of power. Hence, efficiency and full-load operation of the plants can diminish tremendously due to the demand of operating in mode of constant adjusting of capacity to maintain a balance on the grid (Hirth 2014).
The short-term cost of power balancing emanate from the variable nature of photovoltaic power plants. Krebs et al. (2014) argue that it is extremely hard to get the accurate solar radiation at different times of the day and year. Therefore, additional costs are incurred since extra measures and preparations are critical for smooth integration to the power grid.
When the PV power plants are located far away from the consumption regions, then grid related expenses are incurred due to the need for transmission of the power generated by the plants. Power from the plants must be transmitted to the consumer whereby they must be connected to the grid. Additional costs can also arise if grid constrains are increased by integration of the PV power. Finally, additional costs can be incurred if the rate of PV power stations is high such that the power produced cannot be connected and consumed in the grid and the storage facilities do not exist or are inadequate in the system to store the generated power (Krebs et al. 2014).
Photovoltaic systems like other techniques of generating solar power and renewable-green energy production do not emit green gases, hence contribute in the reduction of global warming. However, the technology possesses numerous limitations that make the method undesirable for large-scale power production (Hirth 2014). One of the limitations is adjusting the power generated by a solar power plant whereby the output of the photovoltaic systems including photovoltaic solar power stations, is fixed and cannot be adjusted according to need. Solar arrays used in the solar plants produce power output depending on sun light intensity, which cannot be adjusted. Therefore, whether, power consumption increases or decreases, the rate of output from PV Solar Power Plants will remain constant. On the other hand, some techniques of power generation such as nuclear, fossil fuels, and natural gas plants can be adjusted to increase the level of output when demand is high. Location of the photovoltaic solar power plants is another limitation of the technique (Lave 2013).
The availability of land for plant construction and high sunlight intensity makes the deserts ideal locations for photovoltaic large-scale power generation. However, transmitting the generated power to the consumption areas is a challenge due to the loss incurred in the process. Therefore, to eliminate the problem of transmission, power plants should be set in areas near the consumers, which also attract the challenge of finding enough land to set up the plants and low sunlight intensity. Reliability of photovoltaic solar power plants is another major limitation of technology.
According to Ondraczek (2014), photovoltaic solar plants do not generate power at night; hence, night consumers cannot rely on the technology. Photovoltaic will therefore, require supplementary method of power generation to ensure that the needs of all the consumers are met. Alternatively, power storage techniques are required to store power generated during the day for use at night. However, currently, there exist no efficient and cheap methods of storing photovoltaic solar power plants for use at night. Krebs et al. (2014) also insist that when power PV power is not enough for connecting and consumption in the grid, losses can be incurred due to lack of sufficient storage facilities (Krebs et al. 2014).
Photovoltaic power stations also possess a limitation of emitting more carbon dioxide compared to other sources of green energy. According to Tyagi et al. (2013), PV cells are made up of silicon compounds, which consume a lot of energy to produce. Since the PV power stations require a huge number of solar array with billions of cells, probably trillions, a lot of carbon diode is emitted in the process of producing the materials.
Challenges of estimating the accuracy of solar radiation in different times of the year is another limitation of PV power stations. The challenge leads to increased cost of power integration; the cost of levelized cost of electricity. Therefore, there is a challenge of smoothly integrating power to the grid; hence, extra measures are required enhance integration, which in turn increases the LCOE (Levelized Cost of Electricity) (Singh 2013).
Crystalline Cost Reduction (Reduction of Solar Modules Cost)
The global rise in popularity of photovoltaic solar power stations can be attributed to the increased innovation regarding the technology used to build the systems. Some of the current technological advances are focused to reduce the cost of power generated by the photovoltaic solar power plants. Some of the advancements include the development of solar panels with holographic concentrators, which is under investigation in the International Company Solar that is based in the United State of America (Krebs et al. 2014).
The non-constructed patent for the technology diffractive lens assisted in achieving of 28% percent efficiency compared to the conventional silicon photovoltaic modules. The lens concentrated light into small amount active areas; hence, reducing the amount of silicon required. Therefore, the technique assists in reducing the cost of production because silicon production demands a lot of energy to produce. The holographic techniques concentrates light of required wavelength hence undesired ranges such as infrared do not affect the system. Therefore, the technique assists in minimizing the problem of overheating (Singh 2013).
Morgan solar company, also, provides a promising innovation of solar modules manufactured on high performance triple junction cells, which possess a broad range of sunlight spectrum with a stable output. The reduction in silicon on the power arrays as also reduced Extra Cost incurred when power is generated using the technology. As noted earlier, production of silicon requires a lot energy, which leads to increased carbon emission. Emitting carbon to the environment increases the greenhouse effect. Therefore, necessary measures have to be adopted to reduce the effect, which lead to an increase in extra cost (Lave 2013).
Integrative capacity of photovoltaic Power Stations
Photovoltaic power compared to the other sources of energy such as hydro, wind, and fossil fuels is highly stable. For instance, a study in Germany revealed that the average daily production indicator of turbines run by wind changed thrice in a year. Therefore, in a case where wind is the sole source of energy power blackouts or wastage are expected depending on the design of the power plant (Singh 2013).
In case the power plant is built to supply power to the grid on the higher margin, blackouts will be expected when the plant start producing on the lower margin. Designing the wind power plant to supply on the lower margin will lead to wastage when the facility starts to produce at the maximum level (Lave 2013). A similar case is experienced when fossil fuel plants are used to supply power to the grid, in that power becomes expensive when the price of fossils rise and the market and cheap when the prices go down.
Due to the instability of other sources of power, grid balancing costs increase; hence, power consumer have to pay for the extra cost. Therefore, a stable source of power is required to obtain the correct ratios between powers of intermittent power generation plant in the grid. Appropriate matching of total powers significantly reduces the cost of balancing in a long-term perspective and reduces the required reserve capacities (Desideri & Campana 2014).
Since, the intermittent sources of power possess different causes of regular interruptions, the more they are the bet reducing the variations. For example, a combination of wind and PV power in the ratio of 1:1 can reduce variation of the resulting power. Taking into account of other sources of renewables is necessary to ensure the correct balancing is achieved. Since Photovoltaic power is the most stable compared to the other producers; therefore, can be used to set the rest of the sources at their optimum levels (Karavi et al. 2013).
In short, the current state of technology is focused on efficiency improvement and cost of power generation reduction. Therefore, the current state of technology has resulted in an increased efficiency of Photovoltaic modules, production optimization, prolonged lifetime of the photovoltaic systems, and standard development.
Among the major problem in the global energy sector is generation of cheap, adequate, and clean power. Currently photovoltaic power is clean but is not as cheap as expected and adequate to satisfy the consumers (Koran et al. 2014). Innovations are required in the increase of efficiency compared to other forms of energy generation such as using fossil fuels. Innovation is also required in reducing cost of generating cheap modules such as the holographic solar panels, which can significantly reduce the cost of installing the photovoltaic solar power plants.
Methods of generating cheap modules such as thin film technologies existing currently face a lot of challenges due to their over reliance on scarce elements (Ondraczek 2014). New thin film technologies that utilize earth abundant resources promising flexibility and low weight possess several limitations such as manufacturability and efficiency and could lead to high balance of system costs. Therefore, new technologies for coming up with cheap modules that will in turn lower the costs of installing Photovoltaic power stations are required.
Moreover, development is required to ensure that photovoltaic technology can be used to create a stable combination of intermittent sources to reduce the balancing costs. For instance, since wind power varies throughout the year, fossil fuels are undesirable due to carbon emissions, and biogas based power plants are very few in many countries, determining the correct amount of PV power is essential to ensure that the cheapest combination is arrived (Koran et al. 2014). Arriving at the necessary ratios is a challenge, which requires more research to determine.
However, as current research has focused on development of cheap modules and creating a balance of intermittent powers in the grid and while a considerable progress has been achieved in these individual areas, a challenge of combining the technologies has emerged. Cheap technologies that lead to cheap modules cause the balance of system (BOS) costs to escalate. Therefore, as technological advances are made on either sides they cannot be simultaneously beneficial to the PV power plants.
Regarding technological improvements to lower (BOS) and Solar modules that can lead to cheap, reliable, and efficient PV power, new technologies for combining the two are required (Ondraczek 2014). Therefore, as separate efforts to develop cheap modules and lower BOS are being emphasized in future, more funding, and research focusing on mechanisms that can guarantee smooth integration of cheap PV power (due to use of cheap technology to develop the solar modules) to the grid by reducing the BOS are critical in future.
In addition, in future, technologies combining photovoltaic and concentrated solar power generation can assist in increasing the output of the systems, whereby heat and light components of sunlight will be used to generate power simultaneously. A possibility of thermal power plants relying has been identified in the past. Hence, combining the techniques can eliminate the weakness of PV plants inability to supply power at night (Koran et al. 2014). Hence, a developing a hybrid technology based on the ideology can yields a lot of potential. Therefore, future studies should focus on combining the technologies and improvement of the hybrid system.
In a nutshell, for PV power plants to increase in popularity, future efforts in terms of research, finance, and policies should focus on developing cheap modules such as thin films and effective ways of PV power integration to the grid to achieve reduced BOS costs are required. Further, Extensive and intensive research on efficient technologies to integrate cheap PV power due to reduced cost of modules on the public grid to reduce BOS expenses are required in future. Finally, a combination of PV and thermal solar technologies of generating power are worth consideration in future to increase power generated per annum and eliminate the inability of photovoltaic plants to supply power at night.
Photovoltaic solar power stations possess immense potential in generating large-scale power that is the connected to grid. The power stations inherit the benefits of photovoltaic technology, which include generating clean energy by converting solar energy without emitting carbon dioxide; hence minimizing global warming. The power stations also have a reduced cost of maintenance due to lack of movable parts like many other sources of power such as wind and hydro, whereby heavy machinery is used.
However, photovoltaic solar power stations have some disadvantages, which are a major drawback to the mode of large-scale power generation. The plants lack the necessary efficiency compared to other sources of renewably and considering the type of material used to create the solar arrays. Hence, high cost power generated using the method compared to other technologies of generating power is becomes a very major drawback of the photovoltaic power stations.
Moreover, photovoltaic solar power stations possess several limitations that make the technology undesirable in the market, which include the inability to generate power at night and the increased loss of power during transmission when the site of generation is far away from consumption areas. In addition, the current state of technology is not working efficiently to reduce the cost of power using the approach regarding integration to the public grid; hence, technological and financial support in terms of tax incentives and subsidies are required to ensure that the method remains competitive in the market. In that regard, technology in large-scale photovoltaic solar power generation is making a lot of advances; hence, improving the potential of photovoltaic systems in future.
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