Solarpower refers to the energy derived from the sun in the form of solarradiation. It is either the use of the sun’s energy direct as heat(thermal energy) or using photovoltaic cells in solar panels andtranslucent photovoltaic glass to produce electricity. This powerfrom the sun avoids the costs associated with environmental damagethrough extraction, spills, and dealing with pollution createdthrough combustion. Today, most people are using a grid-tiedphotovoltaic system, which is an electricity producing solar PVsystem that is attached to the utility grid.
Agrid-tied photovoltaic system consists of solar panels, inverters, apower-conditioning unit, and grid connection equipment. They usuallyrange from small residential and commercial rooftop systems to largeutility-scale solar power stations. Each of these major components ofa grid-tied photovoltaic system has different functions. Forinstance, solar panels are now becoming very attractive renewableenergy options, functions by converting sunlight into electricalenergy. The application of solar energy over the past few years hasbeen around for small devices such as calculators, but now it isbeing used to provide power in buildings with the use of solarpanels. Notably, solar is one of the most promising sources ofrenewable energy available today because solar energy is abundant.The rays emanated from the sun can produce energy nearly 1,000 wattsfor every square meter of the earth’s surface. When the solar panelis joined to the local electrical grid, there is a give and takerelationship. A solar panel contains many different solar cells orsilicon cells, which are building blocks of solar panels and theyabsorb the energy from the sun. However, these solar cells and theconductors in the panel convert the sunlight into DC electricity thatthen flows into the inverter [ CITATION Sol04 l 1033 ].
Aninverter is one of the main components of a grid-tied photovoltaicsystem, which converts (DC) direct current to (AC) alternatingcurrent. They are often considered as the brains of the system. Thedirect current cannot be used to run most modern householdappliances, and that is where an inverter comes in to convert toalternating current. The resulting AC converted by this electricaldevice can be at any required frequency and voltage with the use ofappropriate control circuits, transformers, and switching. Notably,handling of the input voltage, frequency, output voltage, and theoverall power depends on the circuitry or the design of theparticular device. Besides, inverters do not produce any power sincethe DC source supplies the power. This device may be a combination ofmechanical effects or can be electronic. However, the AC electricalpower converted by inverters can be used at home, and the excesselectricity that is not used can be fed back to the grid. Someinverters are used for backup power in a network connected home. Suchkind of inverters will use grid power to keep the batteries chargedand in case the grid power fails, they will switch to drawing powerfrom the batteries and supplying it to the building electrical system[ CITATION TMa00 l 1033 ].
Apower-conditioning unit is also one of the major components of agrid-tied photovoltaic system. This unit consists of functional unitssuch as solar charger, grid charger, output selector mechanism,battery bank and a control algorithm. These devices are intended toimprove the quality of the power delivered to the electrical loadequipment. Each device has its function. The other major component ofa grid-tied photovoltaic system is grid connection equipment. Thisequipment can be connected directly or indirectly. For the directgrid connection, the power generation system, which includes solarpanels and the batteries, supplies its output immediately into theutility grid. On the other hand, the output of the power generationsystem for indirect grid connection is fed into the distributionnetwork[ CITATION Sol04 l 1033 ].
Inrecent years, the price for PV systems has rapidly declined due tothe exponential growth of photovoltaics. They differ by market andthe extent of the system. For instance, in 2014, the prices forresidential 5kW systems in the US were about $3.29 per watt, while inthe extremely penetrated business of German the costs for rooftopsystems of up to 100kW declined to €1.24 per watt. However, thesolar PV modules nowadays account for less than half of the system’soverall cost leaving the rest to the remaining soft costs, whichinclude permitting, customer acquisition, inspection,interconnection, financing costs and installation labor [ CITATION TMa00 l 1033 ].
Thelocal governments, federal, and state offer unbelievable solar powertax credits and deductions to support homeowners to switch torenewable power to lower their energy usage and switch to solarpower. The federal government allows deduction of about 30% of thesolar energy system costs of the federal taxes through an investmenttax credit. The (ITC) Solar Investment Tax Credit is one of the mostimportant internal policy tools to promote the deployment of solarpower in the US. The ITC continues to drive growth in the industryand creation of jobs across the country. These incentivesdramatically lower the solar panel system cost or energy efficientproject. The ITC has also made the cost of solar for consumers tocontinue falling. The occurrence of the ITC through 2016 gives marketcertainty for companies to promote long-term investments that driveopposition and technological modernization, which in turn, lowersconsumer’s costs. Besides, these solar tax credits are rebatesoften to make solar power less expensive than power from the utilitycompany. However, these programs are designed to reward earlyadopters of solar power and energy efficiency so that the energyrebate amount per home continues to drop as the allotted funds areconsumed [ CITATION Ric10 l 1033 ].
Off-gridwas the most common application of photovoltaic in the 1970s, buttoday more than 95% of solar installations are grid-tied or on-gird.The cost of PV falling has certainly helped in accelerating grid-tiedsolar, but other facts were the approval of net metering legislationby 40 US states. The current utility policy for purchasing excessenergy from a grid-tied PV array is by net metering. Net metering isan electricity management for utility consumers who operate theiron-site power systems such as photovoltaic systems. The PV systemsare connected to the utility grid through the customer’s mainservice panel and meter. When more power is produced than it isneeded, the excess electricity is returned to the network within thepower meter, converting the meter from its normal direction. As aresult, the meter works in both direction, and one is for measuringthe power, and the other is for measuring the power returned to thegrid. However, the customer pays the net of both transactions [ CITATION Mic12 l 1033 ].
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Hantula, R. (2010). Solar Power. Infobase Publishing.
International, S. E. (2004). Photovoltaics: Design and Installation Manual : Renewable Energy Education for a Sustainable Future. New Society Publishers.
Markvart, T. (2000). Solar Electricity. John Wiley & Sons