The study of DNO Restrictions on Commercial Solar Installations
DNO approval is one of the most important but least paid attention to when businesses think of installing solar panels. The Distribution Network Operator (DNO) decides how your solar PV system will be connected to the grid, the volume of power that can be exported, and the technical specifications that will need to be met in order to install it. Early knowledge of DNO restrictions assists business to plan by size, cost, and ROI of the system.
At Solar Dreams we oversee the DNO process right through to the end, although it is always useful to understand what goes on behind the scenes.
What is DNO and Why it Matters?
- A DNO will oversee and maintain the local electricity distribution network. There are six DNOs in the UK, among which are Electricity North West, UK Power Networks, and Northern Powergrid companies. They provide safe supply of electricity within homes and businesses.
- In case of commercial solar panel installation, the DNO would have to be consulted since surplus energy produced could be sold to the grid. The DNO makes sure that this export is not unsafe, imbalanced and does not overload local circuits. The export of electricity without permission and in the case of larger systems, even connection to the grid is not legally allowed.
DNO Consent: G98 and G99 Standards
DNO standards are based on the national engineering standards: G98 and G99 developed by the Energy Networks Association.
G98 - miniature (less than 16A per phase) Systems
Single phase or three phase systems are included under G98, e.g. 3.68kW or 11.04kW respectively. These are the fit and notify systems – your installer finishes installation and gives notice to DNO in 28 days.
G99 - Commercial and Industrial Systems
Installation of commercial solar PV systems larger than 100kw is G99 approved. The DNO evaluates:
- Local grid capacity
- Voltage fluctuations
- Fault protection levels and systems.
Potential export capacity
They can either accept the system as it is, approve but subject to conditions such as restrictions on export, or insist they upgrade their networks prior to connection.
And typical DNO Restrictions and Conditions.
Export Limitations
One restriction that occurs most often is a limit on the amount of energy that your system can export. As an example, a 500kWp system can be restricted to export 100kW; the remainder will have to be used on-site or throttled.
Dynamic Export Curtailment or Timed
There are DNOs that only permit exports at some times. Businesses might be forced to schedule operations in peak and off-peak allowance Requirements on Grid Reinforcement.
In case of local capacity in your system, then the DNOs might need upgrades on transformers, cabling or substations. Early involvement assists in the detection of these expenditures prior to the installation.
DNO Application Process
- Preliminary Grid Assessment : A feasibility study or a pre-test grid should be done to highlight the possible constraints.
- Formal G99 Application: Submit complete electrical drawing and suggested generation capacity. The DNO is a network impact model.
- Offer and Conditions : Accept a Connection Offer with approved capacity of export, reinforcement requirements and technical requirements.
- Installation and Commissioning: Once it is accepted, the system is installed. Accomplish this through the DNO who oversees testing and compliance.
In G98 systems, it is enough to notify when it has been commissioned.
Timescales and Costs
- Small business industries (below 100kW) can normally require 8-16 weeks to be approved.
- Systems that would require more reinforcement or are larger may require 3-12+ months.
The prices are as low as a couple of hundreds of pounds and extend to tens of thousands on major upgrades.
- Overcoming DNO Limitations
- Maximising Self-Consumption
On-site power generation maximizes the use of solar generated power and makes production consistent with demand. This involves the use of solar power in sheds, solar power in outbuildings or solar electricity in sheds.
One more aspect of integrating battery storage is provided.
Batteries store surplus energy to be used later, reduce the export restrictions, offer backup generation, and allow the participation in the demand response. This is best suited by solar panel and battery kits or solar battery kits.
Export Limiting Controls
The contemporary inverters and control systems can limit exports and maximise the utilisation of internal energy. This makes it adhere to DNO restrictions without making it less productive.
The role of DNO Regulations in the support of grid.
When the renewable generation is more, DNO rules are safe and stable. Such standards as G98 and G99 make sure that the new solar arrays will fit in the network with ease and save your investment and the network.
The management of DNO Compliance at Solar Dreams.
At Solar Dreams, we handle:
- Grid capacity tests and feasibility tests.
- G99 connection applications
- Smart control architectures of export limits.
- Testing and DNO sign-off.
- Solar panel optimizers, solar panel pigeon protection, solar panel bird mesh, solar panel advice, and battery storage.
This helps in the smooth run of the projects and gives maximum performance in the very first day.
Future: The Future of Grid Connections.
DNOs are becoming Distribution System Operators (DSOs), becoming active in the control of generation and demand. Fixed restrictions may be substituted with dynamic export agreements and local trading of energy. Businesses that have flexible assets such as solar panels on flat roof, solar-powered sheds, or solar panels on sheds in the garden will be on a good position to benefit.
Conclusion
Commercial solar projects can be greatly impaired by the early knowledge of DNO restrictions. The smart system design, solar panel installation kits, battery storage, and export control plans are designed to make sure that projects are in line with the regulations and they make the most of the energy available on site.
Solar Dreams takes businesses on a path of DNO, starting with feasibility, to commissioning, and thus, solar adoption is not only efficient but also cost effective and in a way prepared to meet the future.
