SOLAR FAQ : General

Find average monthly consumption (in units) from annual data of your electricity bill and divide it by 135. You get approx idea of how much kilowatt of system is required.

One kw of system needs approx 90 to 100 sq feet of shadow free roof area.

Panels are to be mounted south facing at an angle of approx 15 degrees to horizontal. The angle is important because when the incident sun-rays are normal (at 90 degree), we get maximum output. Generation suffers when panels are not clean, there is shadow on the panel, solar radiation is not strong.

When Sun rays are incident on the Solar Photo Voltaic (PV) panel, the tiny PV cells produces a potential difference across its terminals when hit by the photons (Which are present in light rays).

The voltage so generated by each tiny solar PV cell is accumulated by connecting them on the panel and two terminals come out of each panel as the DC voltage terminals. So, you can treat each of the solar panels as a Battery giving out variable power proportional to the intensity and angle of the incident sunlight.

These panels are grouped together and the power generated is brought at one point. The generated power is DC (Direct Current) and needs to be converted to AC (Alternating Current). This is achieved by Solar Inverter.

The AC Current coming out of Solar inverter can be used to Drive the electrical load, charge the batteries or can be simply fed into the Electricity Grid.

According to the agreement you have with Electricity Distribution company, the AC Current coming out of Solar inverter is fed into the Grid directly. Your energy meter records the consumption as well as the generation of electricity. At the end of billing cycle, the generated units are subtracted from consumed units and you are billed only for the NET UNITS consumed. This way, we save on electricity cost.

The excess generation is carried forward to the next month and is adjusted if required. At the end of year, reconciliation is done and if any excess units are remaining, you shall be paid as per the agreed tariff (as per agreement you had with your Electricity company). So, it is always better not to generate more than our requirement because the purchase tariffs are generally on the lower side.

In traditional Grid Tied system, when the Grid Fails; Immediately the Solar Inverter is cut-off and thereafter all the power generated from Solar is earthed thereby resulting into the loss of generated power. However, if we install Hybrid Solar Inverter, the generated power can be used to charge the batteries for us.