### Grid-Connected PV System  
The primary component of grid-connected PV systems is the power conditioning unit (PCU). The PCU converts the DC power produced by the PV array into AC power as per the voltage and power quality requirements of the utility grid. A bidirectional interface is made between the PV system, AC output circuits, and the electric utility network; typically, an onsite distribution panel or service entrance [30; 31; 32] allows the AC power produced by the PV system to either supply onsite electrical loads or to back feed the grid when the PV system output is greater than the onsite load demand. This safety feature is required in all grid-connected solar PV [33]. One of the important components of an on-grid system is net metering. Standard service meters are odometer-type counting wheels that record power consumption at a service point by means of a rotating disc, which is connected to the counting mechanism. \begin{table}
\begin{tabular}{c c c c c} \hline
**Policy** & **Year** & **Definition** & **Notes** & **Ref.** \\ \hline \multirow{8}{*}{FiT} & \multirow{8}{*}{2011–2016} & The concept of FiTs is that the & & \\  & & yield of the user-generated & & \\  & & photovoltaic system is sold to the & & \\  & & utility grid at a price set by the & & \\  & & utility network. Two meters are & & \\  & & installed; one is used to count the & & \\  & & electricity consumed by the user, & & \\  & & and the second meter measures & & \\  & & the kWh produced by the PV & & \\  & & system and sent to the grid. & & \\ \hline \multirow{8}{*}{NEM 1.0} & \multirow{8}{*}{2016–2019} & NEM enables customers to & & \\  & & product and use solar energy to & & \\  & & satisfy demand. The extra PV & & \\  & & electricity will be exported to the & & \\  & & grid. This surplus power is & & \\  & & subsequently offset by a rate of & & \\  & & MYR 0.31/kWh from the next & & \\  & & electricity bill. & & \\ \hline \multirow{8}{*}{NEM 2.0} & \multirow{8}{*}{2019–2021} & This policy allows a consumer & Each one kWh exported to the & \\  & & who produces photovoltaic energy & & \\  & & to export the excess energy to the & & \\  & & grid, and each kWh is & & \\  & & compensated by another kWh & & \\  & & from the next electricity bill. & & \\  & & & displaced cost of MYR & \\  & & & 0.31/kWh. & \\ \hline \multirow{8}{*}{NEM 3.0} & \multirow{8}{*}{2021–2023} & Similar concept to NEM 2.0, apart & & \\  & & from that it permits indirect & & \\ \cline{1-1}  & & connection to commercial & & \\ \cline{1-1}  & & buildings. The allowed installed & & \\ \cline{1-1}  & & capacity is 75\% of MD for & & \\ \cline{1-1}  & & commercial buildings. & & \\ \hline \end{tabular}
\end{table} 
Table 1: PV policies in Malaysia applied to commercial buildings. The rotating discs operate by an electro physical principle called the eddy current. Digital electric meters make use of digital electronic technology that registers power measurement by solid-state current and voltage sensing devices that convert analog measured values into binary values that are displayed on the meter using liquid crystal display (LCD) readouts [20]. Inverters are the main difference between a grid-connected system and a standalone system. The inverters must have the line frequency synchronization capability to deliver the excess power to the grid. Net meters have the capability to record consumed or generated power in an exclusive summation format. The recorded power registration is the net amount of power consumed--the total power used minus the amount of power that is produced by the solar power cogeneration system [34; 35]. Net meters are supplied and installed by utility companies that provide grid-connection service systems [36]. Net metered solar PV power plants are subject to specific contractual agreements and are subsidized by state and municipal governmental agencies.