Solar Electricity or Photovoltaics (PV)
Solar electricity, or photovoltaics (PV), is light energy converted into electrical energy. Solar cells, which capture the sun’s energy and change it into electricity, are connected to form solar panels or modules, which can, in turn, be connected into arrays to produce more power. Because of this modularity, PV systems can be designed to meet any electrical requirement, no matter how large or small. You can begin with a smaller system that is designed so you can add on later to power your entire home or business!
Solar panels are what most people think of when they think “solar power system.” But the fact is, there are many more components to create a complete system. We have everything that you will need at competitive prices: solar panels, inverters, combiners, batteries, generators, roof mounts and solar trackers, system display and controllers and more!
How Photovoltaics Work
- Solar panels collect the sun’s energy and convert it into direct current (DC) electricity. Except in the case of a battery back-up system being used, you do not “pick your load;” meaning you do not choose which equipment or lights are going to be solar powered. The number of panels you need is determined by your electricity needs.
- An inverter converts the electricity from DC to alternating current (AC) electricity for use in your home.
- In grid-tied systems, a bidirectional electric meter displays net power usage. When you generate more than you use, your meter spins backwards, lowering your electricity bill. When you generate less it spins slowly forward.
- You now produce your own electricity to be used throughout the home. Since there are no moving parts, you don’t have to worry about maintenance. Your system’s production can be tracked with an optional system display & controller from inside your home or via the internet.
- Excess electricity generated is fed back to the utility grid.
Additional information about connecting to the grid and net metering is available on our Grid-Tied Systems page.
PV Systems are Highly Reliable and Versatile
PV systems, originally developed by NASA for space exploration (where repairs are extremely expensive, if not impossible) are highly reliable. A system operates reliably for long periods of time and needs virtually no maintenance.They have no moving parts, so visual checks and equipment servicing are sufficient to keep systems operational.
PV systems can be installed in a yard on ground racking or a pole with or without trackers, on a roof using traditional mounting hardware, or by using flexible laminate modules that are thin and lay flat, creating a seamless look with the rest of the roof. In the photo right, they are visible only as the darker-toned sections on the roof’s south side. Check out our installations gallery to see a wide variety of installation types.
Technically Speaking: Solar Technology
Solar panels, or solar modules, are made up of individual solar cells. The solar cells capture the sun’s energy and change it into electricity. Each cell contains silicon, and when photons hit the solar cell, they are absorbed by the silicon and the energy in absorbed light produces a small electrical current called electrons. Metal grids around the solar cells direct the electrons into wires that lead to power controls and produce electricity. To produce more power, cells can be interconnected to form modules, which can in turn be connected into arrays to produce more power.
Combining modules with the balance of system, or BOS, components creates an entire PV system. This system is usually everything we need to meet a particular energy demand, such as powering a water pump, or the appliances and lights in a home, or, if the PV system is large enough, all the electrical requirements of a whole community.
Solar cells can be made from a wide range of semiconductor materials. Silicon – used to make some the earliest photovoltaic (PV) devices – is still the most popular material for solar cells. These are made in single, multi and poly crystalline cells. Modules are made up of a perfect cell, giving “plywood look,” and it gives a more efficient cell per square inch.
Triple Junction Technology, utilized by Michigan-based Uni-Solar, is three separate layers of amorphous silicon. Amorphous silicon is a thin film and each layer processes one of the 3 primary colors (Red, Yellow, Blue). Thin film utilizes more of the available light than crystalline modules, but it takes twice as much area.