Solar photovoltaic (PV) systems, also referred to as solar electric systems, capture sunlight energy and convert it into electricity. PV systems can be used to power everything in your home from lights and appliances to an electric vehicle.
How Does PV Work?
The graphic below explains how solar electricity is produced, where the energy flows, and the bill-crediting mechanism known as “Net Energy Metering”.
- Individual photovoltaic (PV) cells are embedded onto panels. Sunlight striking the panels is chemically converted into direct current (DC) electricity.
- The DC electricity goes to an inverter that transforms it into alternating current (AC) for household use.
- The utility meter records the net amount of energy (kWh) consumed. When the system creates more electricity than needed in the home, the meter will "spin backward" and the excess electricity is released onto the electric grid and 'credited' to your utility account. These credits help offset the cost of kWh usage at night or on cloudy days when PV systems are not producing as much electricity.
PV solar panels
PV solar panels harness energy from the sun as DC electricity. A variety of solar panels are available.
Inverters
Inverters convert DC into AC electricity for household use or to feed power onto the utility grid. There are two types of inverters: central and micro.
Central inverters – One individual inverter per array. This is the classic technology that is installed with most solar systems. The kW size of these inverters is determined by the total number of panels linked to it. Therefore, any plans to increase the system size due to future appliance additions, should be considered during the initial stages of design. While the main drawback of central inverters is performance limitations, such as shading tolerance, this can be improved with the installation of power optimizers.
Microinverters – One individual inverter per panel. Microinverters allow overall systems to be more tolerant to shade by allowing electrons to bypass any shaded cells, avoiding a severe drop in total production and allowing for more flexible system placement. They more easily allow for future panel additions by simply adding an additional microinverter for each additional panel.
Will monitoring be included?
Both central inverters and microinverters have the option to include monitoring at an additional cost. If you lease the system or enter into a power purchase agreement (PPA), monitoring will be included in the package. With a monitoring system, you will be able to track your PV system’s production on your smartphone or computer.
Benefits of monitoring your system
- Panel-level and real-time production visibility
- Identify system issues/failure quickly to minimize system production losses
- Easy to troubleshoot cause of system issues
What information should the listing agent gather?
During solar home transactions, it is expected that the listing agent will provide the following information to all parties (appraiser, buyer’s agent, etc.).
- Kilowatt (DC) solar system size
- Manufacturer, model number, quantity and warranty of inverter(s)
- Manufacturer, model number, quantity and warranty of panels
- Labor warranty
- Year of installation/utility interconnection
- Ownership of system (homeowner or third-party owner, e.g., lease or power purchase agreement)
- If third-party owner: remaining financial obligations, transfer and lien subordination process
- Type of financing used for system and if any loans remain unpaid, e.g., property assessed clean energy (PACE) loan on the property
- Annual kilowatt-hour (kWh) production of solar system (an indicator of potential savings for the buyer depending on their energy consumption)
Where can the listing agent find this information?
- Ask the homeowner or solar contractor
- Refer to the solar installation contract
- Check the homeowner’s utility bills, Green Button report or utility true-up statement (a yearly recap of solar production and electric consumption that includes credits and debts)
