Traditionally, power on the utility grid flows from power plants to customers. By design, however, the grid is equipped to receive small amounts of power from distributed generation systems, like small solar energy installations, which is known as solar interconnection.
As alternative energy systems gain popularity, homeowners are increasingly feeding renewable energy to the grid. Allowing the power to flow from customers requires an interconnection agreement for solar with the electric company. Certain steps must be completed to receive an interconnection agreement and obtain solar Permission to Operate (PTO).
As photovoltaic (PV) solar power systems become more widespread, utility companies are gaining experience in approving interconnection applications and solar PTO. In most areas, that results in a smoother interconnection process. Read on to learn about solar interconnection with our insights from over a decade of experience in solar design, interconnection, and engineering.
What is an Interconnection Agreement for Solar?
Solar interconnection agreements for solar allow homeowners to draw electricity from power lines when their solar panels aren’t producing enough energy. Utility interconnection also enables many customers to take advantage of net metering (when applicable) with the power company and receive solar credits for surplus power they supply to the electrical grid.
Is an Interconnection Agreement for Solar Important?
PV interconnection is necessary for solar homeowners to take advantage of net metering and receive compensation for the power they supply to the grid. Net metering credits often expire after 1 year and often require a specific type of electric meter. Without solar interconnection approval, surplus electricity would not result in solar credits on electric bills. Keep in mind that net metering is not available in all utility territories, and customers are sometimes compensated at a wholesale rate instead of a retail rate for surplus electricity.
Interconnection agreements for solar are vital for your clients to get the most value from the solar electric system, thus boosting the return on investment. If the solar power system doesn’t have batteries and isn’t connected to the power grid, homeowners get no benefit from the surplus solar power they produce.
Solar interconnection isn’t necessary for off-grid solar power systems. When the grid is nearby, it’s advantageous for most solar homeowners to be connected to it with a grid-tied solar power system. This arrangement allows homeowners to draw power when the solar power system isn’t producing enough power, such as at night or in cloudy weather.
GreenLancer offers numerous solar design and engineering services, including interconnection agreements for solar. Create a free account to shop for permit-ready solar plan sets, interconnection drawings, and engineering reviews.
Process for Interconnection Agreements for Solar
Applying for interconnection requires the following steps for home solar panel systems. Most solar installation companies complete these steps on the customer's behalf.
1 - Submit Solar Interconnection Application
Submit an interconnection application to the utility company to initiate an interconnection agreement for solar. This application should include crucial details about the solar system, such as its dimensions, precise location, and technical specifications. Providing this information ensures that the utility company has the necessary data to evaluate the feasibility and compatibility of the proposed PV system with the existing grid infrastructure.
Your solar interconnection agreement application for solar may also need electrical diagrams, equipment data sheets, and any required permits or certifications. The utility company reviews your solar interconnection agreement application to ensure compliance with safety standards, grid compatibility, and regulatory requirements. Successful approval of the interconnection agreement for solar is critical for integrating the PV system into the existing electrical infrastructure and obtaining solar PTO.
2 - Obtain Solar Permits
The next step in the solar interconnection agreement process is getting your PV permits. Once the application is approved, you'll need to obtain the necessary solar permits from the relevant authorities having jurisdiction (AHJs) to ensure that the installation complies with local and national regulations and safety standards.
Meeting solar permit requirements necessary for solar interconnection commonly requires the following:
Building and Electrical Codes Compliance: Grid-tied solar systems in the United States must comply with the National Electrical Code (NEC), building codes, and local AHJ requirements. NEC standards, which cover various aspects such as wiring methods, grounding, overcurrent protection, and equipment specifications, are updated periodically. It's critical to comply with the latest version, which is currently the 2023 NEC edition.
Structural and Electrical System Design: AHJs may request detailed structural and electrical system design plans for an interconnection agreement for solar to ensure the installation meets safety standards. Our solar design service can help with permit-ready solar plan sets with electrical diagrams.
Equipment and Solar Inverter Specifications: AHJs may require information about solar panels, inverters, and other equipment to verify compliance with safety and performance requirements.
Solar Site Plan and Location: AHJs may need a site plan showing the proposed location of the solar system to assess its compatibility with local zoning regulations and building codes.
Electrical Diagrams: AHJs may require electrical diagrams detailing the wiring and interconnection of the solar system to the building's electrical system. They show the wiring, circuitry, and interconnections, which help identify any potential hazards or issues that could arise during installation, operation, or maintenance of the solar system.
Structural Analysis and Wind Load Calculations: In some areas, AHJs may request structural analysis and wind load calculations to ensure the solar system can withstand local weather conditions. This is most common for ground mounts and commercial PV systems. The GreenLancer network includes licensed engineers who can complete these solar engineering requirements.
Solar Permit Application Fee: AHJs often require an application fee to cover administrative costs associated with reviewing and processing the PV permit application. The fees can vary widely by AHJ, system size, and solar system type.
3 - Solar System Inspection
Following the installation of the solar array, authorized inspectors or relevant authorities inspect to verify that the solar project meets all safety and performance requirements. PV systems are inspected before obtaining an interconnection agreement for solar to ensure the installation complies with safety regulations and is correctly and safely installed.
The solar inspection will verify whether:
The solar system meets NEC and building code requirements and has structural integrity
The solar permit documents match the actual PV installation
There is proper labeling of system components, appropriate disconnects, and safety protocols
The PV system complies with solar interconnection requirements, including proper synchronization, anti-islanding measures, and voltage regulation
4 - Receive Solar PTO
After a successful inspection and compliance with relevant regulations, the utility company grants PTO, allowing the solar system to generate electricity and feed it back to the grid. Solar PTO authorization is essential for legal compliance, solar interconnection, and system activation.
Solar PTO signifies that the system meets safety standards, enables the owner to benefit from net metering, and ensures ongoing monitoring and maintenance for reliable and efficient operation. Obtaining PTO for solar is a crucial milestone in obtaining an interconnection agreement for solar, signifying that the system is ready to harness clean energy. Now, you can officially turn on the PV system, and your client will receive solar energy credits on their electricity bills.
What are Some of the Solar Interconnection Requirements?
There are numerous requirements for connecting a solar system to the grid to promote safety and promote grid stability.
Proper Synchronization: Solar systems must match the grid's frequency (typically 50 or 60 Hz) and voltage. This synchronization is critical to prevent damaging surges and ensure smooth power transfer. Inverters play a key role in adjusting the DC output of the panels to meet grid standards.
Anti-Islanding: Islanding occurs when solar panels continue generating power during a grid outage. Utility companies require anti-islanding protection to prevent backfeeding, which could endanger utility workers repairing lines.
Voltage Regulation: Grid-tied solar systems must maintain voltage levels within acceptable ranges (typically 110V or 240V for residential) to obtain an interconnection agreement for solar. Inverter settings must regulate and adjust power output to avoid grid instability.
Protection Systems: Solar installations must include overcurrent and ground fault protection to mitigate electrical faults, ensuring both the safety of the system and the grid. These measures are often integrated into inverters and breakers, reducing risks of overheating, short circuits, or fires.
Metering & Communication: Solar systems require bi-directional meters to measure energy flow both to and from the grid. Smart meters allow for real-time data exchange, providing utilities with insights into energy production, consumption, and export.
Interconnection Agreement for Solar: This agreement formalizes the technical and legal conditions for connecting the solar system to the utility grid. It includes requirements for inspections, certifications, and ongoing compliance with grid regulations, along with details on how the solar system will interact with utility equipment and local infrastructure. Without an interconnection agreement for solar, homeowners cannot legally operate a grid-tied system.
Information Is In an Interconnection Agreement For Solar
A solar interconnection agreement typically contains essential information that governs the connection process between a solar energy system and the utility grid. This agreement outlines the technical specifications, safety requirements, and contractual terms necessary for the system's successful integration with the grid.
Some key information included in a solar PV interconnection agreement may involve:
Technical Requirements
This section in an interconnection agreement for solar specifies the technical standards the system must meet, including voltage, frequency synchronization, and power quality parameters. For instance, inverters must comply with IEEE 1547 standards to ensure safe and effective solar interconnection, while the system may also need to meet UL 1741 compliance for grid-support functionality.
Solar Equipment Specifications
The solar interconnection agreement outlines necessary equipment specifications, such as the type of inverter, protection devices, and metering systems. These components must meet certain performance and safety benchmarks, with inverters requiring functionalities like low-voltage ride-through (LVRT) to prevent system disconnection during temporary grid disturbances. The metering system must accurately track both energy production and consumption, often with bi-directional meters.
Solar Interconnection Safety Measures
Safety protocols include shutdown mechanisms like rapid shutdown systems (RSS) and anti-islanding protection to prevent back-feeding into the grid during outages. Ground fault protection is essential for avoiding electrical hazards, and equipment must meet National Electrical Code (NEC) safety standards. In commercial projects, protection relay systems may be required to handle higher voltages and more complex interconnections.
Metering Arrangements for Solar Interconnection
The agreement details how electricity production will be measured and reported, typically requiring advanced metering infrastructure (AMI). This allows real-time data to be collected for accurate billing and performance tracking. Depending on the local policies, net metering or feed-in tariff arrangements may be included in interconnection agreements for solar, which determine how your client is compensated for excess energy sent to the grid.
Liability and Insurance
This section defines the responsibilities of both the solar installer and the utility for damages or accidents. For solar interconnection agreements for large-scale projects, liability insurance may need to cover significant damage potential due to grid failures or equipment malfunctions. The insurance requirements may vary, but utility-scale solar installations often carry high insurance premiums due to their potential impact on grid stability.
Fees and Charges for Solar Interconnection
Solar interconnection fees can include costs for technical reviews, impact studies, and equipment upgrades necessary to handle the new solar generation capacity. In some cases, commercial or utility-scale projects may require a more thorough solar interconnection study to assess the impact on grid reliability, which can add substantial costs. Ongoing fees for maintenance or communication infrastructure are also common, especially for larger systems.
Solar Interconnection Study
A formal interconnection study is often required, particularly for commercial and utility-scale solar systems, to evaluate the solar system’s impact on the grid's stability, voltage regulation, and power quality. The interconnection study assesses potential upgrades or adjustments needed to handle the added load safely and ensure that the new energy generation does not disrupt existing grid infrastructure. This involves simulations, short-circuit analysis, and protection coordination to ensure compliance with IEEE standards.
How Long Does The Solar Interconnection Process Take?
The length of the interconnection application process varies depending on the size of the solar array and the utility company. Most solar interconnection agreement applications that meet utility requirements receive PTO in less than a month.
The solar interconnection process can get slowed down by not facilitating utility company requests, such as making the system available for inspection. Also, using incompatible equipment can slow or halt the interconnection process. Some solar installation companies have experienced long delays with the utility company, but this issue is relatively rare and is sometimes due to issues with the utility meter.
How Much Does Solar Interconnection Cost?
The solar interconnection process can vary significantly based on the size and complexity of the system and the utility's requirements. Most residential systems with standard interconnection agreements receive Permission to Operate (PTO) in under a month.
However, for larger commercial or utility solar installations, the interconnection agreement process may involve additional steps, such as impact studies to assess grid stability, which can lengthen the timeline. Technical delays can also occur due to equipment incompatibilities or failure to meet grid safety protocols, like anti-islanding measures or voltage regulation requirements. Utility inspections and transformer or meter upgrades might extend the solar interconnection agreement timeframe, particularly if special approvals are needed.
Turning on a System Without Solar PTO
Turning on a solar system without receiving solar PTO could cause issues, as the utility company hasn’t authorized it. This could lead to fines or shutdown orders, especially if power backfeeds during a grid outage. Also, activating the system without solar PTO might void warranties or lead to insurance issues. It's best to wait for official solar PTO approval to avoid these complications and ensure compliance and safe operation.
Solar Interconnection Agreements With Batteries
PV systems with batteries can still qualify for solar interconnection. In fact, solar energy storage systems can allow your customers to take advantage of time-of-use rates if available through the local utility company.
Time-of-use Rates & Solar Interconnection
In some utility territories, the price per kWh of power varies by the time of day and even the time of year. This encourages customers to consume electricity during times of off-peak demand, thus smoothing out demand. If a solar system includes a battery, your customers have more flexibility in where the power originates (the grid vs. the battery). They can draw power from the battery during times when rates are higher and from the grid when rates are lower. Therefore, batteries allow your customers to save even more on their power bills.
Recent Solar Interconnection Reforms
The recent solar interconnection reforms implemented by the Federal Energy Regulatory Commission (FERC) can significantly enhance the efficiency and speed of integrating solar energy systems into the grid. This streamlined process addresses long-standing interconnection challenges, improving timelines to receive solar PTO and activate solar systems faster.
Streamlining Solar Interconnection Agreements with Order No. 2023
In July 2023, the FERC issued Order No. 2023 to address the growing backlog of solar interconnection requests. This order introduced reforms to simplify the interconnection process for electric transmission providers, helping expedite solar projects by standardizing procedures and reducing wait times. These changes have improved how new solar energy systems connect to the grid.
Clarifications with Order No. 2023-A
In March 2024, FERC followed up with Order No. 2023-A, addressing 31 rehearing requests. This additional order clarified interconnection reforms, ensuring smoother implementation and resolving concerns related to grid integration. Both orders are instrumental in promoting the integration of renewable energy, particularly solar, by reducing procedural complexities and delays.
Impact on Solar Interconnection Agreements
Together, these reforms have accelerated the solar interconnection process, making it easier for developers to meet interconnection agreements for solar requirements. By alleviating bottlenecks in the grid connection process, they contribute to the timely completion of solar projects, facilitating cleaner energy adoption across the U.S.
Solar Interconnection Agreements and PTO Are Critical
Although the PV interconnection and solar PTO process may seem daunting at first, it’ll get easier over time after you’ve navigated it once or twice. Depending on the utility company in question, the process may vary a bit, so there may be a learning curve when applying for grid interconnection with a different utility company. However, the benefits of receiving solar PTO are significant and enable your clients to get more value from their solar energy systems.
GreenLancer can expedite the solar interconnection agreement and permitting process with quality PV plan sets and our solar design services, so you can focus on what you do best. Know that GreenLancer’s partners will manage your interconnection application from start to finish. Complete the form below to learn more.
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