A–Z Reference Quick List
A – AC, AHJ, Array, As-Built Drawings
B – BOS, Base Load, Battery Backup, Billing Meter
C – Commissioning, Conduit, CAC, Customer Usage Profile
D – DC, Degradation Rate, Demand Charge, Design Review
E – Electrical Permit, Energy Audit, Energy Offset
F – Feed-in Tariff, Flashing, Fixed Tilt
G – Grid-Tied System, Ground Mount
H – Home Energy Score, Hostname
I – Inverter, Interconnection Agreement, Irradiance
J – Junction Box
K – Kilowatt (kW), Kilowatt-Hour (kWh)
L – Line Side Tap, Load Profile
M – MPU, Microinverter, Monitoring System
N – Net Metering, NREL
O – Offset, O&M
P – Panel, Permitting, Photovoltaic (PV), Production Guarantee, PTC Rating
Q – QEW, Quote-to-Close
R – Racking System, REC, Roof Assessment
S – Sales-to-Install Timeline, Self-Consumption, SLD, Smart Meter, Soft Costs, SREC, Shading Analysis, String Inverter
T – TPO, Tilt Angle, TOU
U – Utility Interconnection, Utility Rate Plan
V – Voltage Drop
W – Watt, Watt-Hour, Work Order
X,Y, Z – Zero Export, Zoning Requirements
Welcome to our comprehensive glossary of solar industry terms—perfect for homeowners, DIYers, and solar-curious folks. Learn the lingo from A to Z and, for easy reference, broken down by category.
AHJ (Authority Having Jurisdiction)
The local agency—city, township, or county—that reviews and approves solar plans and permits.
Electrical Permit
Issued by the AHJ to authorize electrical work on your property.
Zoning Requirements
Local rules that may limit or regulate solar installations.
AC (Alternating Current)
The type of electricity used in homes and businesses. Solar panels generate DC, which is converted to AC by the inverter.
Energy Offset
The percentage of your electricity usage offset by solar production—e.g., 90% offset means solar is covering 90% of your needs.
Net Metering (NEM)
A billing setup where you earn credits for excess electricity sent to the grid.
Production Guarantee
A promise from the installer or manufacturer that your system will produce a minimum amount of electricity over time.
Smart Meter
A digital electric meter that tracks real-time usage and supports net metering.
Commissioning
The final step where your system is turned on and officially connected to the grid.
Design Review
An engineering check to verify your solar system meets all technical and safety requirements.
Permitting
Getting approval from the city/county for construction and electrical work.
Site Survey
An on-site or virtual assessment to gather data for your system design.
Work Order
The internal document that initiates your system’s installation steps.
Customer Acquisition Cost (CAC)
The total cost it takes to acquire a new solar customer.
Offset
A sales term used to express how much of a homeowner’s energy use will be covered by solar.
Quote-to-Close Ratio
The percentage of sales proposals that turn into closed deals.
Soft Costs
All non-hardware costs of going solar—like permits, financing, and labor.
Third-Party Ownership (TPO)
When a company owns the system and you pay for the energy (e.g., through a lease or PPA).
SREC (Solar Renewable Energy Credit)
Earned for every 1,000 kWh (1 MWh) your solar system generates. You can sell these in certain states.
Feed-in Tariff
A fixed payment rate for solar energy exported to the grid, offered in some regions.
Renewable Energy Certificate (REC)
Similar to an SREC but used more broadly to track renewable energy production.
Array
A group of solar panels working together.
Balance of System (BOS)
Everything in the system except the solar panels—wiring, conduit, inverter, etc.
DC (Direct Current)
The type of electricity generated by solar panels.
Inverter
The heart of your solar system—it converts DC power from the panels into usable AC electricity.
Junction Box
The central point for connecting electrical circuits within your system.
Microinverter
Small inverter attached to each individual panel to improve performance and visibility.
Racking System
The structure that mounts your solar panels to your roof or ground.
Single Line Diagram (SLD)
A technical drawing showing your solar system’s wiring—required for permitting.
String Inverter
One inverter connected to multiple panels in a “string.” Common in residential systems.
Tilt Angle
The angle at which solar panels are installed to capture the most sunlight.
Billing Meter
The utility meter that tracks both what you consume and what your system exports.
Demand Charge
A utility fee based on the highest amount of electricity used at once—mostly for commercial setups.
Interconnection Agreement
A contract with the utility allowing your system to connect to the grid.
Time-of-Use (TOU) Rates
Electricity pricing that changes based on the time of day and demand.
Utility Interconnection
The technical process of getting your solar system hooked up to the grid.
Solar Industry Terminology Glossary
A
AC (Alternating Current) – Type of electricity used in homes; converted from DC by inverters.
AHJ (Authority Having Jurisdiction) – Local government body (city, county, etc.) that enforces building and electrical codes.
Array – Group of solar panels wired together to produce electricity.
As-Built Drawings – Final construction documents reflecting actual installation details.
B
Balance of System (BOS) – All components of a solar system excluding the solar panels (e.g., wiring, switches, inverters, racking).
Base Load – Minimum level of electricity demand over time.
Battery Backup – System to store excess energy for use during outages or at night.
Billing Meter – Utility meter that records net usage or production.
C
Commissioning – Final step of solar installation when the system is officially turned on.
Conduit – Tubing that protects solar wiring.
Customer Acquisition Cost (CAC) – Expense associated with gaining a new solar customer.
Customer Usage Profile – Analysis of a homeowner’s electricity consumption.
D
DC (Direct Current) – Electricity generated by solar panels before conversion to AC.
Degradation Rate – Annual loss in panel efficiency.
Demand Charge – Fee charged by utilities based on peak usage.
Design Review – Engineering check of system plans before installation.
E
Electrical Permit – Authorization from AHJ for electrical work on a solar project.
Energy Audit – Analysis of energy consumption patterns in a building.
Energy Offset – Percentage of a home’s electricity needs covered by solar.
F
Feed-in Tariff – Policy guaranteeing payment for electricity fed into the grid.
Flashing – Waterproofing used around roof penetrations during solar install.
Fixed Tilt – Non-adjustable angle mounting of solar panels.
G
Grid-Tied System – Solar system connected to the utility grid.
Ground Mount – Solar panels installed on the ground rather than the roof.
H
Home Energy Score – Rating of home efficiency that may affect solar decisions.
Hostname (Site Host) – Person or entity owning the property where solar is installed.
I
Inverter – Device that converts DC power from panels to AC for home use.
Interconnection Agreement – Utility contract to connect a solar system to the grid.
Irradiance – Solar power received per unit area (W/m²).
J
Junction Box – Connects solar wiring to prevent overload or shorts.
K
Kilowatt (kW) – Unit of power equal to 1,000 watts.
Kilowatt-Hour (kWh) – Unit of energy representing one hour of usage at 1 kW.
L
Line Side Tap – Electrical connection before the main breaker, often used for solar installs.
Load Profile – Detailed chart of electricity usage throughout the day.
M
Main Panel Upgrade (MPU) – Electrical service panel upgrade often required for solar.
Microinverter – Small inverter attached to individual panels for optimized output.
Monitoring System – Tracks solar system performance in real time.
N
Net Metering (NEM) – Utility billing mechanism that credits solar owners for excess production.
NREL (National Renewable Energy Laboratory) – Government lab supporting solar R&D.
O
Offset – Amount of energy needs met by solar (e.g., 80% offset).
Operations & Maintenance (O&M) – Long-term servicing and system upkeep.
P
Panel (Module) – Individual unit that converts sunlight into electricity.
Permitting – Securing AHJ approval for system design and construction.
Photovoltaic (PV) – Technology that converts sunlight directly into electricity.
Production Guarantee – Warranty on expected kWh output over time.
PTC Rating – Performance-based rating under real-world conditions.
Q
Qualified Electrical Worker (QEW) – Licensed individual permitted to work on energized systems.
Quote-to-Close Ratio – Sales metric showing proposals given vs. deals closed.
R
Racking System – Mounting structure for solar panels.
Renewable Energy Certificate (REC) – Tradable credit for 1 MWh of solar power.
Roof Assessment – Evaluation of roof’s condition and suitability for solar.
S
Sales-to-Install Timeline – Time from contract signature to system activation.
Self-Consumption – Portion of solar power used directly by the household.
Single Line Diagram (SLD) – Electrical schematic required for permits.
Smart Meter – Digital utility meter supporting real-time data and net metering.
Soft Costs – Non-hardware expenses (e.g., permits, labor, marketing).
Solar Renewable Energy Credit (SREC) – Certificate earned for each 1 MWh of solar power; can be sold in certain states.
Solar Shading Analysis – Identifies shade obstructions impacting production.
String Inverter – Central inverter serving multiple panels wired together.
T
Third-Party Ownership (TPO) – Solar lease or PPA (Power Purchase Agreement).
Tilt Angle – The slant of panels relative to the ground or roof.
Time-of-Use (TOU) Rates – Utility pricing based on time/day of energy use.
U
Utility Interconnection – Process of integrating a solar system into the power grid.
Utility Rate Plan – Determines how customers are billed for electricity.
V
Voltage Drop – Loss of electrical potential across a circuit.
W
Watt (W) – Unit of power representing one joule per second.
Watt-Hour (Wh) – Unit of energy used or generated over time.
Work Order – Internal document initiating system installation steps.
X
- none
Y
- none
Z
Zero Export – System setup preventing export of excess energy to the grid.
Zoning Requirements – Local rules affecting solar installations on properties.