Solar PV Overview
Solar electric works by a process called photovoltaics.
Exposed to the abundant free energy of the sun, silicon-based cells get electrons flowing in a circuit.
The cells are grouped in panels; the panels are grouped in arrays. The arrays are mounted on roofs, as awnings, or on poles in calculable alignment with the sun’s path to generate electricity as optimally and effectively as possible.
Usually, the DC electricity from the array is changed by an inverter to AC and is either used in-house or pushed back through the meter, spinning it backwards, onto the utility’s electric grid. That’s called grid-tied PV. Grid tied PV shuts down when the grid shuts down to keep the utility lines safe.
In order to acquire uninterruptible power supply, a grid tied system must have battery backup. For outages longer than than a few days or when there are heavy clouds it is usually necessary to incorporate a generator to recharge the batteries.
Where there is not a grid connection, the electric goes through a charge controller into a battery bank before entering an inverter to supply electric loads. That’s called stand-alone PV, for when the utility is out of reach, long enough to accrue high costs, or for those who want to be independent.
Thanks to generous brilliant people, extensive resources are available to determine the expected solar resource in “peak sun hours” for everywhere on earth, by mapping the sun’s path through the sky and monitoring percentages of cloudy weather. Dayton, Ohio has 4.4 average annual peak sun hours at latitude.
Renewable Energy Contractors learn all they can about effective, code compliant, safe installation practices, they stay current on the latest developments. They design and install beautiful Solar Electric systems for homes and businesses.
Sam Garber 031310-77