Before you can install a solar system, battery, or EV charger, you have to get permission from the Authority Having Jurisdiction (AHJ). The requirements can vary across states and municipalities, however.
For example, some municipalities base permits on National Electrical Code (NEC) and building codes, while others require a professional engineer (PE) stamp during the permitting process.
A PE stamp requires working with an electrical, structural, or civil engineer to review the project plans and provide their “seal of approval.” Typically, this is a third party with engineering knowledge to evaluate site plans and solar designs.
Some cities may not require a PE stamp for all projects. In these cases, a letter from a state-licensed engineer stating that the structure can handle the weight of a solar system is sufficient.
Before you start the solar permitting process, it’s important to determine if PE stamps are required.
What Is a PE Stamp?
Many industries have standards that govern their practices. A PE stamp certifies that a solar power installation, energy storage project, or EV charger has been designed to code and standards.
The engineer has provided a registration seal to indicate that the plan has been approved, shifting liability to them. The stamp may be applied with ink or embossing on paper with a signature and date.
With the shift to digital, some AHJs allow digital engineering stamps. Digital stamps are much faster, saving time and money, and are often preferred.
Each state has different regulations for PE qualifications, but any certified PE can provide the stamp. Typically, this requires a bachelor’s degree, time spent working with another, more experienced engineer, and passing two standard exams.
Types of PE Stamps
AHJs have different requirements for engineer-stamped drawings. The requirements may depend on the climate or the likelihood of natural disasters.
Here are the types of PE stamps:
Electrical engineers can approve electrical designs using solar modules. They typically check the interconnection method, wire sizing, and other electrical components to ensure that the electrical infrastructure can handle the load of solar components.
Civil engineers deal with infrastructure, which includes bridges, roads, airports, and other civil projects. Civil engineers are rarely used for residential and smaller-scale solar projects, but they may be used in commercial or utility-scale installations. EV chargers may also require civil engineering stamps.
The load of a solar system may include vertical loads, horizontal loads, and longitudinal loads. Structural analysis is used to examine the forces of these loads on structures, as well as the forces of wind, snow, seismic shifts, and more. The analysis considers multiple elements, including the type of roof framing, roofing material, site-specific calculations, and the structural design of the racking system.
Obtaining a stamp requires the structural engineer to review the information, calculate the load forces, and evaluate them against the safety and code requirements of the AHJ.
Depending on the AHJ requirements, engineers may be able to provide a digital stamp. Otherwise, it’s necessary to get an ink or embossed stamp on paper drawings.
PE Stamps Are Key for Solar Projects
In areas where PE stamps are required, they’re essential to getting permits and preventing major project delays. If you don’t have an in-house engineering team, you can work with an engineering firm for your solar projects.