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Advanced Energy Solutions (AES): Customized energy projects that use cutting-edge technology and service applications to maximize bill savings, optimize a facility’s load profile, and adapt to new conditions as systems evolve. This is done through a combination of load management, “smart” energy (battery) storage and distributed generation.

Alternating Current (AC): [See “Current”]

Array Size: Also known as system size, is the total DC wattage at Standard Test Conditions (STC).

As-Built Set: [See “Drawings”]

AutoCAD: Acronym for “Auto Computer-Aided Design”. AutoCAD is the computer software SoCore engineers use to create project blueprints.


Behind the Meter (BTM): [See “Interconnection”]

Bid Set: [See “Drawings”]

Build Transfer: [See “Contracts”]


Centralized Generation: Electricity is produced at large power plants and transmitted great distances through power lines to end user. Example: Nuclear power plant

Change Order: Construction work that is added to or deleted from the original scope of work. Change orders need to be signed and agreed upon by all parties.

Circuit Breaker: An automatic electrical switch designed to detect faults and current interruptions in order to protect the electrical circuit from overloading or short circuiting.

Commercial and Industrial (C&I): Commercial and industrial facilities include retail, logistics, manufacturing, warehouses, healthcare, education, REITs and multi-site portfolios.

Commercial Operating Date (COD): [See “PM”]

Community Solar Garden (CSG): An off-site, large-scale solar installation (1 MW+). Multiple community members may use the energy produced by the installation, including local businesses and residences in a community.

Conductors: An object or type of material, such as a wire, that acts as a path for electrical current to flow.

Conduit: A tube or channel used to protect electrical wiring.


  • Build Transfer: The customer buys the system, rather than leasing, in which there is a single initial capital expense that yields fixed energy hedge for the life of the asset. This option gives customers the highest return on their investment and maximizes their energy savings.
  • Power Purchase Agreement (PPA): A Power Purchase Agreement is a contractual agreement in which ENGIE agrees to own, operate and maintain the solar system. The customer agrees to host the solar system on its roof/property and purchases the system’s electric output from ENGIE for a predetermined period.
  • Operating Lease: A financial agreement in which ENGIE, rather than the customer, owns the solar system, and retains any rebates and tax incentives, in exchange for periodic “rental payments” from the customer.

Current: The flow of electric charge in a conductor between two points having a difference in potential (voltage).

  • Alternating Current (AC): The type of electricity used to power homes and businesses where electrons constantly reverse direction.
  • Direct Current (DC): The type of electricity produced by solar panels in which the current maintains a constant flow.


DART: Days Away from work, job Restrictions, and/or job Transfers. DART is an OSHA safety standard metric that helps employers determine how many workplace injuries and illnesses occur within a calendar year.

Data Acquisition System (DAS): The process of measuring an electrical or physical condition such as voltage, current, temperature, or pressure. The components of ENGIE’s DAS (i.e. monitoring system) include a data logger, cell modem, revenue grade meter, weather station, and software.

Depth of Discharge: Percentage of battery capacity that has been used.

De-rate Factors: Elements that may reduce the production of a solar system. Examples include panel soiling, shading, and inefficiencies.

Direct Current (DC): [See “Current”]

Disconnect: An easily accessible switch used to shut off a solar system.

Distributed Generation (DG): Power generation at the point of consumption that allows customers use their own power, rather than power coming from traditional power plants.


  • As-Built Set: The final set of design drawings used for the construction and installation of all of SoCore’s projects. The As-Built set shows the exact dimensions, geometry, and location of all elements of the work completed.
  • Bid-Set: Drawings used to get an indicative bid on a project.
  • Interconnection/Permit Set: Drawing sets used to apply for and receive interconnection approval and permits.

DSIRE (Database of State Incentives for Renewable Energy): An online database that provides information on solar incentive programs and policies by state.


Electrical Grid: An interconnected network of electric energy generating stations, high-voltage transmission lines, and energy distribution lines that deliver electricity from suppliers to consumers.

Electrical Load: An electrical component or portion of a circuit that consumes power.

Elements of a Solar System
Within the below definitions, the term ‘solar’ is interchangeable with ‘photovoltaics (PV)’.

  • Solar Cell: The smallest electrical element within a solar module that converts sunlight into electricity.
  • Solar Module: A physically connected collection of solar cells that converts sunlight into electricity, also referred to as a solar panel.
  • PV String: A number of modules or panels that are electrically interconnected in a parallel series to produce more current.
  • Solar Array: An interconnected system of solar modules that function as a single electricity-producing unit.
  • Solar System: The complete set of components for converting sunlight into electricity.
  • Solar Direct System: A simple system in which electricity can only be generated when exposed to sunlight.

Energy Information Administration (EIA): Government agency that analyzes and provides energy information to help with policy-making and education.

Energy Storage: [See “Advanced Energy Solutions”]

Engineering, Procurement, Construction (EPC): Acronym commonly used in the industry when relating to the development and operations of a site.

Equipment Grounding Conductor (EGC): Non-current carrying conductor used to connect any exposed metal to ground.

Escalator: Some solar contracts include an annual escalator, which is a percentage increase for the cost of solar power. Typical escalators range from one to three cents per kilowatt hour.


Feed-In Tariff (FIT): An incentive used to encourage deployment of renewable energy. Customers receive a set price from a utility for the renewable energy they generate and provide to the grid.

FERC (Federal Energy Regulatory Commission): An independent agency that is responsible for the regulation of the interstate transmission of electricity, gas, and oil. FERC regulates interstate transmission of energy and since 2005 has had a strong role in regulation of renewables into the grid.

Fixed-tilt Array: A solar array mounted at a fixed angle. The array does not move, as opposed to a tracker system, which rotates to follow the sun.


Geographic Information System (GIS): A system used to capture, visualize, analyze, question, store and interpret all types of geographical and spatial data to better understand the development of potential solar sites.

Grid-Connected System: Solar system that is connected to the utility grid, allowing any additional electricity to be fed back to the grid.

Grid Parity: Occurs when the cost of generating alternative costs less than or equal to the price of purchasing power from the grid.

Grounded Conductor: A circuit conductor that normally carries current, and is connected to ground. Also known as the neutral.

Ground Fault: Occurs when electricity travels outside an intended path and attempts to reach the ground by the shortest route.

Ground Mount: A solar system mounted on racking on the ground.



  • Incentive Claim Form (ICF): Form submitted to the government to receive incentive tax credits (ITC) after system is purchased, installed, and put into operation.
  • Performance Based Incentive (PBI): Incentives that are paid based on the actual energy production of the PV solar system.


  • Behind the Meter (BTM): A type of interconnection on the customer’s side of the utility meter. As a result, power produced offsets load used by the facility that would have otherwise been drawn from the utility grid.
  • Interconnection Agreement: The legal process for connecting a solar system to the grid. This agreement includes technical and contractual terms that the system owner and utility must follow in order to ensure safe operations.
  • Line side connection: Commonly called a Supply-Side connection, it represents an interconnection that occurs on the utility’s side of the main disconnect, such as a breaker or fused switch.
  • Load side connection: Interconnection that occurs on the customer’s side of the main disconnect, such as a breaker or fused switch.

Inverter: Converts DC power produced by solar modules to AC power.

  • Micro-inverters: An inverter that converts DC generated by a single solar module to AC. Micro-inverters contrast with conventional string and central solar inverters, which are connected to multiple solar modules or panels of the PV system.
  • String Inverter: A device for converting DC to AC power from a string of solar panels.

Investment Tax Credit (ITC): A 30% monetary tax credit, set to expire December 31, 2016, that is available for utility scale, commercial, and residential sized projects and is used to offset federal income tax liability.

Irradiance: The solar radiation that strikes a surface, usually expressed in kilowatts per square meter. The sun’s energy output every single day, and solar irradiance varies significantly from one location to another, so this number changes drastically throughout the course of the year and from location to location..


Junction Box: A container for electrically connected PV strings, intended to conceal them from site and deter tampering.


Kilowatt (kW): A standard unit of electrical power equal to 1,000 watts (power is the rate at which energy is generated or used).

Kilowatt hour (kWh): A measure of energy that reflects the amount of kW produced over a period of time, or one kilowatt of electricity supplied for one hour. Commonly used as a billing unit for energy delivered to consumers by electric utilities.


Line side connection: [See “Interconnection”]

Load side connection: [See “Interconnection”]


Mechanical Completion: [See “PM”]

Micro-inverters: [See “Inverters”]

Module: [See “Elements of a Solar System”]

Monocrystalline: PV cells manufactured from a single crystal with perfect silicon lattice structure that are known as the most efficient cells commercially available.

Mounting Equipment: Equipment/apparatus used to fasten PV modules to the roof or ground

MUSH: An acronym for municipalities, universities, schools, hospitals.


National Electric Code (NEC): A standard for the safe installation of electrical wiring and equipment in the US. While this is not a federal law, it is typically adopted by states and municipalities in an effort to standardize their enforcement of safe electrical practices.

National Electrical Manufacturers Association (NEMA): The organization that sets standards for electrical products, systems, and technologies.

Net Metering (NEM): A billing mechanism that credits solar system owners for the electricity they add to the grid. Allows residential and commercial customers who generate their own electricity from solar power to feed electricity they do not use back into the grid. Some states have passed net metering laws to encourage the use of renewable energy, while other states oppose the mechanism.

Net Zero: A building that generates as much energy as it uses.

NFPA: Acronym for National Fire Protection Association


Off-grid system: A system that is not connected to the utility grid and is the only power source for connected loads covering 100% of the electrical needs.

Off-taker: The purchaser of the electricity.

O&M: Acronym for Operations & Maintenance.

Operating Lease: [See “Contracts”]


Panel: [See “Elements of a Solar System”]

Peak Demand: Term used in energy demand management describing a period in which electrical power is expected to be provided for a sustained period at a significantly higher than average supply level. Also known as peak load.

Peak Shaving: The process of reducing the amount of energy purchased from the utility during peak hours when the charges are the highest.

Performance Based Incentive (PBI): [See “Incentives”]

Permission to Operate (PTO): [See “PM”]

Permitting & Interconnection (P&I): [See “PM”]

Photovoltaics (PV): The direct conversion of sunlight into electricity through the use of semiconductor materials.

Power Purchase Agreement (PPA): [See “Contracts”]

Production Factor: Factor that estimates how much energy will be produced from a given system size, tilt, efficiency and location.

Project Management (PM)

  • Commercial Operating Date (COD): The date that a solar/storage installation is officially turned on. In order to receive COD, To begin operating, ENGIE must receive verification that the installation has been built to all contractual and safety specifications.
  • Mechanical Completion: As defined by ENGIE, Mechanical Completion is the point at which a system is mechanically complete (i.e. when all components are built). This milestone does not include the commissioning of the site or the completion of punch list items that may arise during commissioning.
  • Permission to Operate (PTO): Once the utility has been out to fully inspect a solar system, a notice is generated that notes the utility’s approval and provides a date that the system can officially start running.
  • Permitting & Interconnection (P&I): A project must receive approval from the Authority Having Jurisdiction (AHJ) and the utility in order to build and turn on a solar system. AHJ approval typically includes building and electrical permits. Utility approval includes an Interconnection Application and/or signed Interconnection Agreement.
  • Substantial Completion: As defined by ENGIE, Substantial Completion is the point after Mechanical Completion when three additional milestones have been achieved: (1) commissioning (and the completion of any punch list items); (2) receiving Permission to Operation from the utility and local jurisdictions, and (3) completing a successful System Acceptance Test (SAT).

Purchase Order (PO): A document that indicates types, quantities and agreed prices for products or services that SoCore will provide to the customer.

Public Utilities Commission (PUC): A governing body that regulates the rates and services of a public utility.

Public Utility Regulatory Policies Act (PURPA): A law requiring utilities to purchase power from independent companies that could produce power for less than what it would have cost for the utility to generate power, intending to promote energy conservation.

PV String: [See “Elements of a Solar System”]

PVSyst: A computer software package for the study, sizing, simulation and data analysis of complete PV systems, allowing us to model the estimated production of a solar array.

Polycrystalline: A semiconductor material composed of small crystals, used to make photovoltaic cells using a high purity polycrystalline form of silicon.


Renewable Energy Credits (REC): Renewable Energy Credits are created for every megawatt-hour of renewable energy created. They can be retired or sold to electricity suppliers needing to meet their RPS requirements.

Remote Site Analysis: Gathering and reviewing data for a possible PV installation site using aerial photos and top-of-the-line software technology.

Renewable Portfolio Standards (RPS): A state mandate that requires utility companies to source a certain amount of energy from renewable resources.

Residual Value: Assumed value of the system at the end of modeled life, including the costs to remove and redeploy the system.

Roof Rent: The solar company pays a building owner to use their roof for a solar installation site.


Sales Layout: A preliminary design created by ENGIE’s engineering team that is used to develop an accurate project proposal for clients.

Scope of Work (SOW): A formal document that outlines all of the work to be completed under the terms of the contract, including requirements, deliverables and reports.

Seasonal rate schedule: A utility tariff that charges a different rate for energy used, based on the time of year.

Solar Energy Industries Association (SEIA): The Solar Energy Industries Association is the national trade association for solar energy and related businesses, and represents all organizations that promote, manufacture, install and support the development of solar energy.

Single line diagram: A simplified notation for representing a three-phase power system.

Site visit: When a member of ENGIE’s team visits a potential solar site to assess its viability.

Solar Carport: A solar-covered parking structure.

Solar cell: [See “Elements of a Solar System”]

Solar noon: The time when the sun is highest above the horizon on any day.

Solar window: When a solar system site is free of shade and exposed to sunlight.

String Inverter: [See “Inverter”]

Substantial Completion: [See “PM”]

Surge Capacity: The maximum power that can be provided over a short time.

System Load: The energy requirement or demand on an energy producing system, usually expressed in watts.


Thin-film: A flexible and lightweight solar material used in specialty markets and on smaller applications, such as commercial window lamination and solar powered calculators.

Tie-In: The stage of installation in which a solar system is turned on and connected to the utility electrical grid. During this stage, a facility’s electricity needs to be shut off in order to safely connect the solar.

Tiered electrical rates: A rate system with a number of tiers with different baselines, or the minimum the customer will pay. Once the customer goes over the baseline, they are charged more.

Tilt-and-roll tracker: Active sun trackers that have primary support running north to south, allowing the array of panels to pivot over the bar in an east to west direction throughout the day, in order to maximize sunlight exposure.

Time of Use Rate (TOU): Instead of a single flat rate for energy use, time of use rate plans are higher when electric demand is higher.

Tracking Array: A device that orients a solar array toward the sun, following its path to maximize the solar radiation being received.

Transformer: An electromagnetic device used to reduce or increase the voltage or AC electricity, as it transfers the electrical energy from one circuit to another.


Value of Solar Tariff (VOST): A rate design policy that gives customers with solar installations credit for the electricity generated by a photovoltaic system. The tariff clarifies how much energy is sold in each direction and at what rate the energy is valued.

Virtual Net Metering (VNM): A tariff arrangement allowing multiple homeowners to use the same metering system, sharing the output from a single off-site energy generating facility.


Watt: The standard unit of power, used to specify the rate at which electrical energy is absorbed or transferred.