PARTS OF A SOLAR PHOTOVOLTAIC SYSTEM
A Solar Photovoltaic (PV) system is named as such as in such a system electricity (voltaic) is generated from light (photo). The electricity thus generated is clean and renewable. There are various components of a solar PV system as described below –
Photovoltaic (PV) Solar Panels
Net Energy Meter
Other Electrical Equipment and Protection Devices
WORKING OF A SOLAR PV SYSTEM
In a solar PV system panels are connected to produce electricity. The panels are connected with the solar PV inverter which is able to draw maximum amount of available power from the panels. Since the electricity produced by the panels is in DC form and the loads in any building work on AC current, the solar inverter converts the DC electricity into AC form and feeds it into the main distribution panel of the building.
The solar electricity is used in the building in case there is a requirement, else it is exported into the grid.
For accounting for import of conventional electricity from the grid and export of solar electricity into the grid, a Net Meter (also called Bi-Directional meter) is used.
Now there are two scenarios in which the system could be functioning as illustrated below:
Case 1: Net Consumption
Case 2: Net Generation
Case 1: Say, in a summer evening, the Sun is dim but you have kept your lights, fans, air conditioners, etc. on. At this time, your PV system might be generating less than your actual power requirement. In this case, you would end up consuming power from the PV system, as well as importing balance power from the grid. In this case too you electricity import from the grid is drastically reduced.
Case 2: Say, on a bright Sunday afternoon, you have gone out with your family to watch a movie. At this time, the power consumption in your home would be negligible, but your PV system would be at its peak. In this case, the extra electricity generated by your PV system would directly be exported into the grid, and your ‘net meter’ would deduct this exported electricity from your account.
The on-grid solar PV system turns off in-case of grid outage to prevent electricity from being fed into the grid as a safety measure. However in case of a hybrid solar PV system, the solar system functions in an off grid mode too and provides back up power to critical loads.