Solar Basics: A Glossary of Key Solar Terms


Like any industry, solar energy has its own unique terms, abbreviations, and lingo. Learning their meanings is a great way to better understand the entire solar installation process from beginning to end. That’s why we’ve put together this useful glossary of key solar terminology you’ll often hear solar professionals use.

Site Analysis

One of the first steps of the solar installation process is the site analysis, where a solar professional inspects the location of a proposed solar energy system for factors that will affect its size, layout, and energy output. These factors include solar access (how much sunlight the location receives), roof pitch (tilt angle), roof azimuth (orientation relative to north or south), and objects that contribute to shading (trees, other buildings, etc.). While a number of these data points can be collected virtually, a site analysis is best conducted in person during a physical site visit. The solar professional will require access to the building’s roof in order to assess its condition and the amount of usable space available for the proposed array. Access to the building’s electrical room will also be necessary so that measurements can be taken of the existing infrastructure to ensure the space can accommodate vital solar system equipment.

Permitting & AHJ

Permitting is not unique to the solar industry, but an important topic nonetheless. This is the step in the installation process where your solar developer files the required paperwork with the local AHJ (authority having jurisdiction), which usually is the department of buildings. The goal is to confirm the structural and electrical safety of the system and that everything is up to code. At this stage, your solar developer will also file an application for interconnection with the utility company (see below), as well as determine what kinds of solar incentives your business may be eligible for. Solar incentives are money-saving (or generating) opportunities afforded to owners of solar energy systems on federal, state, and local utility levels. Once all permitting and approvals are in order, the installation can proceed.


Following a kickoff meeting with the customer where important dates, times, and logistics are discussed, the project moves into the mobilization phase, or the point at which physical work actually begins. The solar developer’s project management team facilitates the delivery of all equipment needed to complete the job while carefully coordinating with the manufacturer, installation team, and the client to ensure minimal disruption to onsite business operations. You can read more about the solar project management process here.


Most corporate solar installations are grid-tied systems, that is, systems that are hooked into the utility grid via a process called interconnection. This operation requires a brief shutdown of the building’s electricity, which is coordinated with the utility company. Interconnection allows for a two-way flow of electricity: the customer can draw energy from the grid to supplement their solar production, as well as send surplus power into the grid in exchange for credits on their utility bill — a practice called net metering. As mentioned, application for interconnection is submitted to the utility company in the early stages of the project. Approval time can be lengthy, but solar developers such as PowerFlex can manage the entire process on behalf of the client to guarantee a smooth process.


Before the system can be considered officially installed, a round of testing called commissioning must be carried out to guarantee everything is working properly. Engineers wearing PPE (personal protective equipment) carefully check wiring, connections, system voltage and current, grounding, and a host of other things that impact not only the performance of the system but also the safety of its operation.

PTO (Permission to Operate)

The final step in the installation process is getting the PTO, or permission to operate. This is determined by the utility or another AHJ following a thorough inspection of the system. Only after PTO is obtained will the system be approved for regular energy production.

O&M (Operations & Maintenance)

After a solar energy system is installed, it’s smart to opt for a comprehensive O&M (operations & maintenance) plan. O&M is an ongoing process that ensures optimal performance, though most systems will require very little upkeep over their lifetime, which can be 25 years or more. Some common O&M procedures include panel cleaning, trimming vegetation around the array, and monitoring energy output to make sure the system is performing as efficiently as possible. O&M providers can also manage your participation in solar incentive programs. (Read more here about the role of O&M.)

Now that you understand some of the most common terms used during the solar installation process, the next step is to learn how solar energy can specifically benefit your business. For that, contact us at PowerFlex for a free consultation. Over the past decade, we’ve helped big corporate and industrial clients fulfill their sustainability goals while drawing great returns on investment through the installation of an onsite solar system.