Solar energy has gone mainstream. Everyone knows what solar energy is. They have seen residential solar energy systems mounted on the many homes of Edison. However, few people know what goes into those shiny solar energy systems. Here is your crash course on the components of the ubiquitous systems that harness residential solar energy for Edison homes.
Made up of photovoltaic cells, or PV cells, solar modules are the most visible parts of the solar energy system. Also known as solar panels, they are installed on your roof to capture the energy from the sun. It is these photovoltaic cells within the solar module that convert solar energy into usable electricity. Solar PV modules are commonly available in a range of sizes and efficiencies, with most solar modules being installed residentially today 60-cell modules between 350-400 watts. Higher wattage PV cells are also available in the market for a price and some achieve this higher wattage by being a larger size at 72 cells. These 72-cell modules are the most common in-ground mounts and commercial solar installations.
As the name suggests, these are used to mount solar modules to the roof. They allow rows of solar modules to be mounted in an array to harness more energy. They are also pleasing to look at. They can be used on roofs, poles, and the ground. The components will include solar rails, brackets, and flashing which will protect your roof from leaks. Normally there is a 3-5 inch gap between the roof and the solar racking.
Array DC Disconnect
This solar system component is used to disconnect the solar power from the rest of the assembly. Since they make it possible to disconnect the solar panel array, they make maintaining the panels easily.
Solar power is converted into direct current or DC by the PV cells. However, all residential fixtures and home appliances run on alternating current or AC. The inverter converts DC into AC. Most solar installations these days use Micro-inverter technology. This means the inverters are located underneath the solar module which is out of site for you. The physical component you may see if the combiner box which quite literally combines all the solar modules into a single energy source.
Bi-Directional Meter and Revenue Grade Meter
After the solar installation, the utility company will install a digital bi-directional meter. These devices measure the quantity of electricity the household or business uses from the grid. Alternatively, they can also measure the amount of electricity sent from the solar system to the grid, which is necessary for the homeowner to be compensated in a process known as “net metering”
In addition, in states where performance-based incentives (PBIs) are applicable the solar installer may install a revenue-grade meter that tracks the total production of the solar array. The reading from this meter is what will be used in selling SRECs for example.
Not unique to the solar energy system, a breaker panel serves the same purpose as it does in traditional grid power settings. The breaker panel is installed where the power source connects to the house’s circuit. Circuit breakers prevent appliances from drawing too much power and shorting.
Solar power is only available while the grid is operational. To meet the household’s power needs during a blackout, the solar system must store surplus power generated during the day for use during an outage. This is an optional component.
The charge controller is present in systems with a battery backup. True to its name, a charge controller regulates the charging of the batteries. It ensures that the batteries only charge and discharge when required.