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How does a Solar PV (Photovoltaic) System work? |
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How does a Solar PV (Photovoltaic) System work?
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First, Solar panels installed on the roof or elsewhere convert sunlight into
electricity.
Typically, you'll need a south-facing roof that is not shaded by trees or
other obstructions. We have device (called a Solar Pathfinder) that can tell if
shade is present on your roof at any time of the year.
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| This power from the solar panels, generated as Direct Current, is sent to a
device called an inverter.
An inverter has several jobs.
1 - It converts the Direct Current form the solar panels into Alternating
Current, which is what your household appliances use.
(Some systems, such as 'off-grid' systems in houses that are too remote for
the utility to reach do not need an inverter because all of their devices run on
direct current). RV's and boats often have direct current devices, too.
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2 - The inverter matches the alternating current to the alternating current (AC) that
is coming form the utility grid. Inverters must meet exacting standards in order
to be approved for use. The California Energy Commission manages a list of
approved inverters here: http://www.consumerenergycenter.org/cgi-bin/eligible_inverters.cgi
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3 -The Inverter sends the electricity to the main circuit breaker panel in
the house. From there, the electricity can go into the house to run appliances
or, if there is more electricity being generated than is is being used, it will
go back into the utility grid. If permitted by local Net-Metering laws, this
will spin your electrical meter backwards... effectively selling power back to
the utility. |
4 - The inverter 'watches' the utility grid so that it can shut down,
immediately, if the utility grid shuts down. This way, if a storm or accident
breaks an overhead electrical wire then your solar system will not send power
into the electrical system and endanger people. Photovoltaic PV solar systems
will keep your lights on during a power failure if you have batteries
attached to the system.
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How Solar Works
