How a Residential Solar Power System Works

 If you want to use solar power but don’t want to own your own system, you can lease or buy a PPA from a company that will install and maintain the system for you. These arrangements typically include a long-term contract.

A grid-tied PV system uses a central inverter to convert DC electricity from solar modules into AC electricity that connects to your service panel. Some newer systems use microinverters on each panel, allowing for individual module performance monitoring.

Solar Panels

When sunlight hits solar panels, they create an electrical charge. This electricity passes through a solar inverter to get converted into alternating current (AC) that you can use at home or business.

The inverter also acts as “the brain” of your solar system by logging performance data throughout the day. It also enables Con Edison to track your energy production so that any power you export back to the grid can be credited to you on your next bill – an arrangement known as net metering.

There are two types of solar panels used for residential systems – monocrystalline and polycrystalline. Monocrystalline panels, made of high-purity silicon, are generally regarded as the most efficient. Polycrystalline panels are a little less expensive but are not as efficient. Both are available in black, which makes them more easily blended into roofs. In addition, blocking and bypass diodes may be incorporated into each panel string to help handle partial array shading that would limit power generation.

Inverter

An inverter transforms the direct current electricity from your solar panels into alternate current electricity that can be used in your home. It also manages the flow of energy between your solar panels and the grid in systems with battery storage.

The inverter uses electrical switches (called transistors) to change DC electricity into AC power. This is a complex process that converts the energy from a DC source into a smooth, pure sine wave that can power appliances and run your household.

Most residential solar power system use single inverters that are installed near your service panel and electricity meter. Some of these inverters include a built-in power optimizer to prime the DC electricity that enters the inverter, which can help them work more efficiently. Microinverters are another option that attach to each individual solar panel and electrically isolate them from one another, so small amounts of shading or debris on a single panel don’t disproportionately reduce the output of the entire array.

Grid Connection

The inverter converts the DC electricity from your solar panels into clean mains AC (alternating current) electricity that can be fed back into the grid or used for home use. If your local power company offers net metering, every excess kilowatt-hour of energy sent to the grid will earn you a bill credit equal to its retail value.

Your electricity meter will be fitted with a bidirectional kWh meter that allows you to track the flow of electricity generated and consumed in your home. Energy is usually consumed in the morning and evening when demand is highest, so any excess energy generated by your solar system during these times will be sent to the grid through your meter.

A grid-tied system will need to remain connected to the power grid as it can’t generate enough electricity during nights and cloudy days, or to keep your lights on during a grid outage. However, some of the latest grid-tie systems feature micro-inverters that eliminate the need for a central inverter and can be installed on each roof-mounted solar panel.

Monitoring

With insights into energy production and consumption, monitoring solutions enable owners to optimize their home energy use and minimize reliance on grid electricity. This leads to greater energy independence and lower utility bills over time.

Solar monitors provide valuable information, letting you know that your system is producing the energy it should be and whether there are any issues that might affect performance, such as shading or an electrical fault. Many systems also offer alerts, which help you identify and fix issues before they impact your energy production or lead to an inexplicably high utility bill.

Depending on the model, some systems allow remote access via a mobile app or web portal, allowing you to track energy production while on vacation or compare performance trends during your lunch break from any device with an internet connection. In addition, some systems, such as SolarEdge’s solution paired with power optimizers on each solar panel in the array, provide visibility to performance characteristics at the module-level.