Page 90 - GRIHA Manual Volume III - Introduction to National Rating System
P. 90
Renewable energy application 83
disconnects the power supply from the load, thus, avoiding discharge of the battery. A charge
controller must be compatible with the type of battery used. Many charge controllers have a
LED display on the front to display the charge status.
4. Inverter: An inverter is a power-conditioning unit made of solid-state electronic devices
that convert DC type current generated by solar PV systems into AC type current. The main
function of a grid-interactive inverter is to act as an interface between the supplied voltage
and frequency characteristics and those of the grid. Inverters can be classified into rectangular,
trapezoid or sine shaped depending on the form of the output voltage. The best but most
expensive inverter output voltage is in the form of a sine wave. For larger systems, three-phase
inverters are available in the market.
Mounting options
There are various options for mounting PV panels. However, all of these are dependent on the area
of the PV panels to be installed. The area is determined based on the load requirement, electricity
usage pattern, technology, and overall efficiency of the PV system. The total area required includes
the area of the panels as well as the area required for accessing the panels.
# Mounting on roof: This is the most convenient place for installing solar PV panels as it provides
an unobstructed area for solar access. In case of flat roofs, PV panels are mounted at an angle
that exposes the panels to maximum incident solar radiation throughout the year to achieve
maximum efficiency. During mounting, it should be ensured that any roof penetration is
properly weatherproofed. Another important issue to be considered while installing PV system
on roof is the structure of the roof, and the load that the existing roof can take without causing
any structural damage.
# Shade structure: Besides the roof, the PVs can also be mounted on structures like patio. These
could even become the complete patio cover, eliminating the need for a shade structure for
the patio.
# Building Integrated Photovoltaic (BIPV): With the help of new technologies in the field of PV,
photovoltaic can be integrated into the building envelope itself making them an integral part of
the building roof or façade structure. BIPVs are PV panels integrated into the building structure
during construction. They can be used in areas like skylights, glass atrium roofs, curtain, and
structural glazing systems on the façade. BIPVs help in cutting the heat gain while allowing
light to pass through.
Design methodology
Design of an SPV system mainly depends on the type of application for which the generated power
will be utilized. Number of panels and batteries in a system is based on the required total load of
the system, which, in turn, is dependent on the equipments that will be powered by the designed
SPV system.
Following is a step-by-step methodology for designing a solar PV-based power generation unit
for buildings.
1. Resource assessment: Climate and solar radiation pattern for the region and for the building
should be studied. Availability of adequate solar radiation, ambient temperature, and wind
velocity are the essential parameters required for SPV system design for any location. These
parameters are likely to vary widely from site to site. Hence, availability of data about all these
parameters is very important for designing an optimum PV system.
disconnects the power supply from the load, thus, avoiding discharge of the battery. A charge
controller must be compatible with the type of battery used. Many charge controllers have a
LED display on the front to display the charge status.
4. Inverter: An inverter is a power-conditioning unit made of solid-state electronic devices
that convert DC type current generated by solar PV systems into AC type current. The main
function of a grid-interactive inverter is to act as an interface between the supplied voltage
and frequency characteristics and those of the grid. Inverters can be classified into rectangular,
trapezoid or sine shaped depending on the form of the output voltage. The best but most
expensive inverter output voltage is in the form of a sine wave. For larger systems, three-phase
inverters are available in the market.
Mounting options
There are various options for mounting PV panels. However, all of these are dependent on the area
of the PV panels to be installed. The area is determined based on the load requirement, electricity
usage pattern, technology, and overall efficiency of the PV system. The total area required includes
the area of the panels as well as the area required for accessing the panels.
# Mounting on roof: This is the most convenient place for installing solar PV panels as it provides
an unobstructed area for solar access. In case of flat roofs, PV panels are mounted at an angle
that exposes the panels to maximum incident solar radiation throughout the year to achieve
maximum efficiency. During mounting, it should be ensured that any roof penetration is
properly weatherproofed. Another important issue to be considered while installing PV system
on roof is the structure of the roof, and the load that the existing roof can take without causing
any structural damage.
# Shade structure: Besides the roof, the PVs can also be mounted on structures like patio. These
could even become the complete patio cover, eliminating the need for a shade structure for
the patio.
# Building Integrated Photovoltaic (BIPV): With the help of new technologies in the field of PV,
photovoltaic can be integrated into the building envelope itself making them an integral part of
the building roof or façade structure. BIPVs are PV panels integrated into the building structure
during construction. They can be used in areas like skylights, glass atrium roofs, curtain, and
structural glazing systems on the façade. BIPVs help in cutting the heat gain while allowing
light to pass through.
Design methodology
Design of an SPV system mainly depends on the type of application for which the generated power
will be utilized. Number of panels and batteries in a system is based on the required total load of
the system, which, in turn, is dependent on the equipments that will be powered by the designed
SPV system.
Following is a step-by-step methodology for designing a solar PV-based power generation unit
for buildings.
1. Resource assessment: Climate and solar radiation pattern for the region and for the building
should be studied. Availability of adequate solar radiation, ambient temperature, and wind
velocity are the essential parameters required for SPV system design for any location. These
parameters are likely to vary widely from site to site. Hence, availability of data about all these
parameters is very important for designing an optimum PV system.
