Solar energy can be harnessed to create electricity.
conversion is referred to as photovoltaics. The photovoltaic process
converts sunlight directly into electricity, generally in the form of
direct current. Individual solar cells (where the photovoltaic
conversion occurs) are then linked together to form individual solar
modules. The modules can then be linked together to form solar module
arrays, increasing the electrical power available for charging the solar
power systems batteries.
A simple home system consists of a PV array, a charge controller, a
battery bank a DC fuse box, an inverter, and a 120 volt AC circuit
breaker box. The PV array produces electricity when the sun shines.
The charge controller regulates the flow from the array to the battery
bank. When the battery bank is low, the charge controller feeds all of
the electricity from the array to the batteries. As the batteries
approach a state of full charge, the charge controller tapers the supply
of electricity to prevent overcharging of the batteries. At night it
prevents a reverse flow of current from the batteries to the array. The
battery bank stores the electricity as low voltage DC, normally at 12
volt or 24 volt. The electricity is distributed through a DC fuse box
to power low voltage DC appliances. The batteries supply electricity to
a device called an inverter which changes the low voltage DC to 120 volt
alternating current and then sends it to an AC circuit breaker box. The
charge controller and inverter are purchased in a specific voltage and a
specific size based on the proposed performance. The batteries and PV
modules, however, are modular. A PV array may consist of one PV module
at 12 volt, or 10 modules producing 10 times the current, but still at
12 volts. Likewise, a battery bank may be enlarged by increasing the
number of batteries to allow more storage at the same 12 volts. A
system may be enlarged at any time by simply adding more PV modules and
increasing the number of batteries. A solar array sizing worksheet,
insolation tables, a load use chart, and a battery sizing worksheet are
provided to assist you in determining your needs.
Ready to start thinking about your system? Give us a call today at (208) 865-1101.