Solar Panel System

Types of Solar Rooftop Power Systems
A typical rooftop solar power system has electricity-generating photovoltaic panels,
commonly known as solar panels, on top of a house or building. But there is much
more to it…
On-Grid System or Grid-tied System
These systems are designed to work in conjunction with the grid or simply put your
electricity supply. The electricity you generate using this system is fed back to the
grid. A net meter is installed along with this system to keep track of the electricity
consumed by you versus what you generated and fed back to the grid resulting in
savings which gets reflected in the bill. It does not work when the grid is down.

Off-Grid System
These systems store the electricity produced by conversion in batteries and utilize
the stored energy by converting it back to AC as and when required. The rising cost
of other power sources and the increasing demand of electricity, especially in high
power cut or no grid areas, has resulted in increased demand for such systems. The
reduction in battery prices over the years has further brought the system cost down.
What is a Rooftop Solar Power System all about?
Solar panels:

Solar panel is comprised of multiple PV (photovoltaic) cells that convert sunshine to
electricity. Two types of PV Panels are there – while one comprise of “Polycrystalline
Cells”, the other one contains “Monocrystalline Cells”. Polycrystalline cells are
effectively a slice cut from a block of silicon, consisting of a large number of crystals.
They have a speckled reflective appearance and are very thick. They are less
expensive to produce and more suited for Indian conditions. Monocrystalline cells
are cut from a single crystal of silicon- they are effectively a slice from a crystal. In
appearance, they have a smooth texture and you will be able to see the thickness of
the slice. These are slightly expensive to produce. Based on the area available for
solar installation, the required capacity of solar panels can be calculated. Call
our solar expert to know your solar potential and get your solar journey started.

Inverter:

After solar panels, the most crucial component of a residential solar power plant is
an inverter. It acts as an interface which converts power produced by solar panels
into electricity that can be consumed by appliances. The type of inverter being used
depends on the kind of solar power system you are going for. Grid tie solar power
systems need high efficiency power inverters that can feed power from solar panels
directly to grid for optimizing its performance. They are designed to quickly
disconnect from the grid if the utility grid goes down (anti-islanding) as a safety
feature for the linesman working on the grid. Another kind of high efficiency solar
inverters are there for the off grid solar power system that can charge batteries
both from solar and grid power. The inbuilt MPPT (Maximum Power Point Tracking)
charge controllers in some good quality inverters extract up to 30% more power
from solar panels.
Mounting Structure:

It is the most critical part as it acts as the skeleton for the entire system, a sturdy
structure will result in years of power generation as it needs to withstand strong
winds and other natural forces. The type and orientation of the structure varies to a
great degree depending on multiple factors associated with the location where the

solar power system needs to be deployed. The structure for rooftop solar
installation on a flat roof is completely different than that for a slanted roof. The
height of your roof is another major factor which determines the composition and
alignment of the structure. The quality of the material used has to be as per the
MNRE (Ministry of New and Renewable Energy) specified norms. The structure
needs to be made of galvanized iron, which is anti-corrosive making the solar power
system last long.

Cables:

You can’t use any regular cable for your solar power system. Specialized cables
custom made for residential solar power plants are used to ensure minimal loss of
electricity being generated. They are UV protected, strong and long lasting enough
to withstand the rigors of nature – be it peek summers, incessant rains or thunder
storms. Use of any ordinary cable is a big safety hazard with high chances of
electrocution for the people in vicinity of the system. Bad quality wire will make you
system ineffective and more expensive.

Peripherals:

These are the elements which are essential for proper functioning and safety of the
system. No compromise must be made on their quality or it will jeopardize the
entire solar power system. In terms of their functioning, while Junction Boxes are
used to conceal the wiring connections all across the system, Conduits on the other
hand are used to protect the wiring of the solar power plants, they can be rigid or
flexible or a mix of both based on the requirement. Lightning Arrestors are deployed
to save the entire set up in case of lightning strike, especially during monsoon while
Earthling, which is a grounding system connecting the residential solar power plant
to earth, is done in order to give passage to excess electricity during lightning strike
and safeguarding the entire system in the process.

Batteries:

Apart from these, if you are going for an off grid solar solution, solar batteries are
one of the crucial components as they allow you to store the electricity generated
by the solar plant and use it in case of power outages or in case of no mains. A good

battery would be the one which gives long back up and requires very less
maintenance (less frequent water top-up).
Installation:

Lastly, but most importantly the installation of the solar power system needs to be
done with precision in order to generate maximum electricity through the solar
power plant. No two rooftops are the same therefore the process requires system
design and careful supervision to ensure proper installation of the solar rooftop
power plant. Solar panels used in any solar power system should be installed facing
South direction. Tilt angle of solar panel should be between 8 and 33 degree in
India, but it varies as per the height of the installation. Solar panels must be grouted
using anchor bolts or concrete foundation to ensure durability in rough conditions.
UPS and batteries must be installed as close to the panels as possible to minimize
DC transmission losses. One needs to ensure that the maximum permissible voltage
is not exceeded when connecting the panels in series. There should be a minimum
gap of 5 mm between two solar panels to allow for any expansion in materials. The
solar panels being interconnected must be of the same type (mono or poly) and
same power class. There should be no shade or shadow on the solar panels as this
may lead to losses, formation of hotspots, etc.