What Is Solar - PV
SOLAR PHOTOVOLTAIC (PV)
Solar photovoltaic (PV) power involves using crystalline panels to convert energy from the sun into electricity for use in your home or business.
The basic unit is a solar cell made up of thin layers of silicon, a semi-conductor. When photons falling from the sun interact with the silicon, electrical charges are generated as direct current (DC). The PV modular panel is made up of multiple PV cells and is the principal building block of the PV system. Wired together, the PV modules produce direct current (DC) that is transformed to alternating current (AC) by an inverter.
The inverter sends the AC to your home's electrical panel, which supplies electricity directly to your appliances, lights and other electrical devices. If more electricity is being produced than consumed, then the excess is rerouted from your utility meter into the utility grid where you are credited for later use, a process known as net metering.
The entire system is commonly known as a grid-tied PV system.
Batteries can be added to a grid-tied system for backup power in case power from the utility is lost.
Remote, off-grid solar power systems use batteries exclusively to store electricity for later use. They are used in remote areas where it is not practical to connect to the utility grid. The batteries are installed in a solar power system after the PV panels and before the inverter.
SOLAR PV COMPONENTS
SOLAR PANELS
Solar modules or photovoltaic (PV) panels are the major components of your systems. The key ingredient is silicon, a semi-conductor that converts sunlight into electricity. Solar costs are primarily influenced by the silicon components in the panels, which accounts for approximately 60% of a PV systems cost. Panels are typically crystalline or a thin film.
CRYSTALLINE PANELS
Monocrystalline are the most efficient form, converting 12%-20% of the sun's energy into electricity, and is also the most expensive due to high production costs. Multi or polycrystalline silicon, although slightly less efficient than the monocrystalline, also is less expensive.
THIN FILM PANELS/BIPV
Amorphous silicon or thin film is silicon atoms cut into a thin layer and rather than being applied to a wire grid as a crystalline panels, are deposited on flexible or rigid substrates producing a laminate. These can also be applied to building integrated photovoltaic (BIPV) panels in the form of roof shingles/tiles or architectural glass. Thin film, although the least expensive and least efficient, has better shade tolerance and high temperature performance.
INVERTERS
Inverters transform DC electricity from your solar panels into AC electricity to power your home or business. They can send excess power to the utility grid and pull power from utility lines. Because of their importance they can account for 10% of the cost of your system. They last approximately 15 years, so need to be replaced once during the life of the system. Although most grid tied inverters are designed to operate without batteries, battery based models are also available.
MICROINVERTERS
Microinverters are small inverters mounted with under the
solar panel that make each panel operate as a separate unit. By separating the
inverter into multiple units, the amount of power generated is increased by 15 -
20%.
METER
Typically grid-tied solar systems will have AC electricity flowing
to and from the utility grid. In order to measure and record the flow of
electricity, your utility company may provide you with a bi-directional meter.
In most states where net metering incentives exist, electricity produced in excess of what you use during the day is sent back to the grid causing your meter to spin backwards. During the night, the accumulated credit is used as you draw electricity from the grid.
The excess generation will be carried forward and credited to your next bill over a 12-month period. The customer is given full retail value for the excess electricity produced. Although you may pay less the following month because of the excess generation, at the end of your 12-month period (year) excess production is not reimbursed. Therefore, it is best to size the system to your needs.
To check your state's net metering policies go to www.dsireusa.org
SOLAR MONITORS
Solar monitors allow you to track your system's daily operation, recording power produced and consumed, and ensuring
optimal performance. "Display only" monitors primarily display how much power your inverter is producing whereas
"web based" monitoring allows access to performance data if troubleshooting is required.
RACKS AND MOUNTING
A good quality rack and mounting system is an important component that shouldn't be taken for granted. Whether ground, pole or roof mounted, they can allow for a variety of specific tilt angles. All systems installed by Simplex Solar offer the highest quality racking and hardware
available in the industry. Because a PV system produces the most energy when the modules are directly facing the sun, trackers are
available to follow the sun's path throughout the day maximizing an array's output.
To learn about the costs of solar Click Here
