Product Knowledge

Understanding the main solar terminology will help you better understand what you’re talking about and present yourself as a figure of authority when speaking to homeowners. You don’t need to understand everything inside and out like an electrical engineer would, but there are a handful of terms that are important to understand.

• Watt/Kilowatt: Watts are a unit of measurement for power, we often refer to the term kilowatt which is 1,000 watts. 
• Kwh (kilowatt hour): a kwh or kilowatt hour is a unit of measurement for energy, meaning the amount of power (watts or kilowatts) required over a certain period of time. For example: A 10 kw system can generate 10kwh if the array gets full sun for one hour.
• PV (photovoltaic): Most solar panels are PV meaning they are photovoltaic. This means they are made up of solar cells that convert sunlight into electricity.
• TPO (third party ownership): TPO is a commonly used term to describe a solar system that is not owned directly by the homeowner. This typically refers to either a lease or a PPA (power purchase agreement).
• PPA (power purchase agreement): A PPA is a power purchase agreement. Rather than leasing the equipment, the homeowner is agreeing to purchase the electricity produced from their system for a set price per kwh (kilowatt hour). For example: If a homeowner signs a PPA that generates 12,000 kwh per year and their agreement rate is .18 per kwh, this would mean the homeowner is paying $2,160 per year or $180 per month for this system. Because the system is not owned by the homeowner, they would not be eligible to receive the ITC (investment tax credit), because this can only be claimed by the purchaser of the system. So the ITC would go to the finance company that owns the system, this often results in a discounted monthly rate for the homeowner.
• Lease: A lease is an agreement where the homeowner is paying a set monthly rate to lease their solar system equipment rather than purchasing the system. Because the system is not owned by the homeowner, they would not be eligible to receive the ITC (investment tax credit), because this can only be claimed by the purchaser of the system. So the ITC would go to the finance company that owns the system, this often results in a discounted monthly rate for the homeowner.
• Purchase: There are two ways a homeowner can purchase a solar system. They can pay cash or they can finance the system, in either scenario they would be eligible to receive the ITC (investment tax credit) since they’re the owner of the system. Financing the system means they will pay monthly installments for 5-30 years until the balance is paid and the system is owned outright. Financing typically involves interest rates as well as a “dealer fee” in their agreement.
• ITC (investment tax credit): The ITC is an investment tax credit that is offered by the federal government for anyone that purchases a solar system. At the time of this writing the current ITC is 30%, meaning that 30% of the gross cost of the system can be claimed in the form of a tax credit on the owners taxable income.
• String inverter: A string inverter is an inverter that takes multiple strings of panels that connect to a singular inverter to convert the electricity from DC (direct current) to AC (alternating current).
• Micro inverter: A micro inverter is a device that connects to a singular panel to convert the electricity from DC (direct current) to AC (alternating current). Unlike a string inverter, a micro inverter controls the output of a single panel, this way if one panel isn’t working the other panels continue to operate and produce power like normal.
• BOB (black on black): A commonly used term to describe the aesthetics of a solar system is BOB meaning the entire module is black. There are no silver frames or visible silver lines in the modules. Most homeowners prefer this type of module from an aesthetic perspective.
• Net Metering: Net metering is a billing mechanism that credits solar energy system owners for the electricity they add to the grid. For example, if a residential customer has a PV system on their roof, it may generate more electricity than the home uses during daylight hours. If the home is net-metered, the electricity meter will run backwards to provide a credit against what electricity is consumed at night or other periods when the home's electricity use exceeds the system's output. Customers are only billed for their "net" energy use.
• Module: A single photovoltaic panel made up of solar cells.
• Battery: A solar battery is a device that you can add to your solar power system to store the excess electricity generated by your solar panels. You can then use that stored energy to power your home at times when your solar panels don't generate enough electricity, including nights, cloudy days, and during power outages.
• DC/AC: DC (direct current) is the electric current produced by solar panels. Thanks to inverters we can convert the DC into AC (alternating current) power which is usable for various household appliances and applications. AC power is sometimes referred to as “usable electricity” since that’s what is used to power everything in our homes.

‍