It is one of the parts that tends to catch people out. Panels can be installed, systems can be designed, but without grid approval, the project cannot move forward.
Every solar installation connects to the wider electricity network. That connection has to be agreed with the local Distribution Network Operator, often referred to as the DNO. They are responsible for making sure the network can handle what is being added.
This step can shape system size, timing and cost before anything is installed.
The DNO manages the local electricity network. That includes cables, substations and the infrastructure that delivers power to buildings. They are not energy suppliers, but they control how electricity flows through the network.
When a solar system is proposed, they assess whether the network can accept the additional generation. That includes both importing electricity and exporting excess power back into the grid.
Their role is to maintain stability across the network, not just for one site.
Most commercial installations require approval before work begins.
If power is sent back to the grid, limits may apply.
Some areas have limited capacity, affecting what is possible.
Smaller systems may follow simplified processes, but most commercial sites go through a formal application.
An application typically includes details about the proposed system, such as size, expected generation and how it will connect to the existing electrical setup. Site information, location and technical specifications are also provided.
This information allows the DNO to assess how the system will interact with the local network. In some cases, additional data or clarification may be requested.
The more accurate the submission, the smoother the process tends to be.
The DNO reviews the application and checks network capacity in the area. They assess whether the system can be connected as proposed or whether changes are needed.
In some cases, approval is straightforward. In others, conditions may be applied. These could include limits on how much electricity can be exported or requirements for additional equipment.
Where capacity is limited, more significant changes or upgrades may be required.
Export limits control how much electricity a site can send back to the grid. These are often set to protect the network from overload.
If a system generates more electricity than the building uses, the excess would normally be exported. If an export limit is in place, that excess may need to be reduced or managed differently.
This can influence system design, including the use of controls or storage to manage output.
Timescales can vary depending on the size of the system and the complexity of the network in that area. Some applications are processed relatively quickly, while others take longer if additional checks are needed.
Delays can occur where network capacity is tight or where upgrades are required. These situations often involve further discussion and planning before approval is granted.
It is one of the less predictable parts of the process.
If capacity is limited, the DNO may offer alternatives. These might include reducing system size, applying stricter export limits or suggesting network upgrades.
Upgrades can involve additional cost and time, which may affect the overall project. In some cases, businesses choose to adjust their plans rather than pursue more complex solutions.
It becomes a balance between what is possible and what is practical.
The outcome of the DNO process often shapes the final system. Export limits, connection points and technical requirements all feed into how the installation is designed.
In some cases, this may lead to changes in system size or the inclusion of additional equipment. It is not unusual for designs to evolve as more information becomes available.
The goal is to create a system that works within the constraints of the network.
Understanding that this step exists is a good starting point. Early discussions during the survey or design phase can highlight potential issues before formal applications are made.
From there, the process becomes more structured. Applications are submitted, responses are reviewed and decisions are made based on what is achievable.
It is not always the most visible part of a solar project, but it is often one of the most important.