Alternating Current (AC): An electric current that reverses direction within the circuit 60 times per second and is easier to transfer over long distances. This is the primary current used with residences and offices in the United States.

Array: Also known as photovoltaic (PV) array, this is an interconnected system of PV modules that function as a single electricity-producing unit. The modules are assembled as a discrete structure, with common support or mounting. In smaller systems, an array can consist of a single module.

Balance of System (BOS): A comprehensive term that refers to the mounting structure of the array, wiring, conduits, switches and metering equipment.

Direct Current (DC): Represents a single directional flow of energy that starts in one place and ends in one place. Not used for residential service circuits and cannot transfer far without losing energy.

Electric Grid (utility grid): A network of power providers and consumers interconnected by transmission and distribution lines that are operated by one or more control centers.

Grid Tied: Homeowner is connected to the traditional electric grid from where energy is typically drawn. A grid-tied PV system will be able to produce energy for the home to consume or feed energy out into the grid for public consumption. Anything fed into the grid is accounted for through your utility net meter. It is important to understand that the system is tied to the local electric grid and will be shut down when the grid is shut down. Your Sunnova PV solar system cannot operate independently of the grid, i.e., your solar system will not sustain power for your home in the event of a blackout.

In Service: The final stage of the solar installation process that indicates a solar system is operational and generating power.

Interconnection: The connection of a solar system to the electric grid that enables bidirectional transmission of power.

Itron Monitor: The instrument used to measure solar system production.

Inverter: A power-conditioning piece of equipment responsible for turning the DC electrical current produced by the PV modules into AC electrical current that is consumable within your household electrical service.

Kilowatt (kW): 1,000 watts (W), a measure of the output power of your PV system.

Kilowatt-Hour (kWh): 1,000 watt-hours, a measure of the energy output of a kilowatt-sized system for one hour.

Net Meter: The meter installed by the utility company that records energy flow in and out of your household electrical service in order to properly credit your PV system with energy output.

Permission to Operate (PTO): A letter or other official document issued by utility companies granting authority for a solar system to operate and generate power.

Photovoltaic (PV): A means to generate electrical power by converting solar radiation into electrical current.

Power Purchase Agreement (PPA): An agreement between two parties, one that generates electricity and one that purchases electricity, which defines what is expected of each party. Payment specifics and the amount of electricity that will be provided to the purchaser are often included in the PPA, but ultimately the needs of both parties and the structure of the local market will dictate the terms of the PPA.

Puerto Rico Electric Power Authority (PREPA): The electric utility company for Puerto Rico.

Solar as a Service (SAAS): The concept of providing solar power as a service instead of requiring homeowners to purchase or finance their solar systems. The SAAS structure makes solar power more affordable by eliminating upfront costs and ongoing expenses for maintenance and repairs.

Solar Lease: A 25-year contractual agreement that provides a homeowner with solar energy through the rental of a solar system, for a fixed monthly amount, with the benefits of the Sunnova Solar as a Service model. Benefits include no upfront costs or deposit, exhaustive quality assurance and control, an iron-clad product warranty and worry-free maintenance, among others.

Solar Ownership: The purchase of the solar system with a 25-year contractual agreement, for a fixed monthly amount, with the benefits of the Sunnova Solar as a Service model: no upfront costs or deposit, exhaustive quality control, iron-clad product warranty and worry-free maintenance.

Solar Renewable Energy Certificate (SREC): A renewable energy certificate that represents one MWh (1,000 kWh) of solar energy generation. In states that require a certain proportion of electricity generation come from renewable sources, utilities can purchase SRECs to meet the requirement rather than build the generation capacity themselves.

Solar Service Agreement (SSA): The agreement between a homeowner and solar service provider that defines the terms and conditions for solar service.