The Sun Is a Powerful Force!
Solar energy has the potential to satisfy our conventional energy needs in unforeseen ways. By using the sun’s solar radiation to generate thermal energy, we have the ability to achieve self-sufficient energy production. Thus, obviating the necessity for dependence on non-renewable energy sources. The sun’s compelling energy potential renders clean, recyclable, non-hazardous, efficient, and affordable energy readily producible in large volumes. So how does solar energy work?
Solar Electric (PV) Systems
The following is a simple description of the basics of a solar electric, or “PV” system. Solar electricity is generated by a method known as photovoltaics, or PV, for short. Photovoltaic cells convert sunlight into electricity using semiconductors that produce the photovoltaic effect of conversion. More details can be found in the article, “Solar explained: Photovoltaics and electricity” by the U.S. Energy Information Administration.
Solar Panel Materials
Typical materials used to make solar panels are derived from various types of silicon. Some of the most widely-used panels are constructed of monocrystalline or polycrystalline solar cells. Both monocrystalline and polycrystalline solar cells are widely used in solar panel manufacturing and offer reliable and renewable energy solutions. The choice between the two depends on factors such as space availability, budget, and desired efficiency.
A thin-film solar panel is a type of solar panel that uses thin layers of semiconductor materials to convert sunlight into electricity. Unlike traditional crystalline silicon solar cells, which are typically several millimeters thick, thin-film solar cells are only a few micrometers thick, allowing for flexibility and versatility in design and application.
Thin-film solar panels are manufactured using various semiconductor materials deposited onto a substrate, such as glass, plastic, or metal foil. The most common types of thin-film solar cells are constructed from mixtures that are based on amorphous silicon (a-Si), cadmium telluride (CdTe) or copper indium gallium selenide (CIGS).
These materials are formed into the individual solar cells which are then linked together to form a single solar panel or module. A single solar panel may be used to produce electricity, or several of them may be strung together as part of a solar array to form the basis of a greater-producing solar electric system. Solar Electric (PV) systems can be used both residentially and commercially.
Converting the Electrical Current
Since the electricity produced by a solar cell is direct current (DC), and the vast majority of appliances and electrical devices use alternating current (AC), the PV power must be converted from DC to AC before it can be used in the home. This is done by directing the current coming from the solar panels to a power inverter. See our blog post titled, “AC DC – Powerup, Let’s Talk Inverters!” for a fun explanation about inverters!
Next, the power will be directed to one of the two areas of the PV system. Either to a battery backup, or to the home’s main power panel that is connected to the electric utility grid. These are two distinctly different ways of handling the PV power produced by your solar electric system.
Solar batteries store electricity in DC form, so the inverter is best placed downstream from the batteries. This will allow for the electricity to be used safely in the home as it’s been converted to AC power. The question remains, do you need battery backup? Our blog post, “To Battery or Not to Battery; That Is the Question!” might be helpful if you are contemplating this decision.
Staying Connected to the Grid
Those who remain grid-connected (or “grid tied”) do not need to store their PV power, but rather have it “tied” to the utility system by simply having it connected to the main power main switch. This will off-set the actual use of utility-supplied power by the amount of PV power that was produced. In most cases the owner has PV production that is providing somewhat less than the total that they need over the course, say, of a given month.
There may be times however, during any given day, that a PV system produces more than is being used. When this occurs, the system is net producing electricity and essentially “spinning the meter backward”. This is managed and recorded using a utility-installed bi-directional meter that tracks the electricity as it moves in either direction. Either from the utility to the home or vice versa. The owner is credited for their power production supplied to the grid. The rates paid or credited to the customer are determined by the utility company. These are generically termed as net metering agreements and they specifically state the terms of rates that a utility will pay, or credit, to the customer for any net electricity production that their PV system provides, or “puts up on the grid”.
SVE Can Help
If you are interested in unlocking the full potential of solar electric power for your home or business, contact SVE, call 678.833.5191 or email us and we’ll be happy to answer your questions and help you understand how solar energy works and what it can do for you!