Frequently asked questions for Distribution Network Operators

You can request your current capacity from your DNO or energy provider, by sharing the MPAN number of your connection.  

You can also find your capacity on your electricity bill under “Assigned capacity”. The value is expressed in kVa (Kilo-volt-amperes). 

If you don’t know your MPAN number, your electricity supplier can provide it to you through your client number. 

Network usage data such as network availability heat maps, which can indicate where network capacity already exists, can be found on the respective DNOs open data portal. 

We would advise to call your supplier first. The DNO can come out to your site to tell you this information but there will be a charge for this. The roll out of smart metering should help with this.  

Network usage data such as the substation utilisation and operational metering, which can indicate the utilisation of the distribution network, can be found on the respective DNOs open data portal. 

Yes, for any load the DNO should be notified. This is for any heat pump no matter the size even if you think you have capacity. This is because heat pumps can be disturbing loads (harmonic effects). 

Note, for PSDS projects, it is a grant condition to ensure you have notified your DNO. 

Yes, you will need to let your DNO know if you want to install EV charging points. They will need to check if there is capacity in the area for the amount of charging points you're wanting to install. 

This is the maximum demand and agreed capacity you have within your supply contract, and future demand calculated by your installer or electrician. This will give you any headroom that you have and the DNO will check this along with any harmonic effects of the heat pump. The DNO will then approve or quote for any upgrade. You cannot just fill up any spare capacity or headroom with heat pumps as the motors they have affect the network and will need to be assessed.   

There is constantly a queue of people waiting for capacity, so as soon as you give capacity back it will go to the next person in the queue. This means if you want to re-apply for capacity previously given up you will need to apply again and join the queue. 

The DNO will ask for all harmonic and flicker data that can be provided so that they can analyse harmonics that cause the most disturbance.  

• Single-phase supply
  • Check fuse ratings beneath the meter; typical capacity is 15–18 kVA for an 80A fuse. 
• Three-phase supply
  • Supplies range between 45–69 kVA depending on infrastructure. 
• Options for information: 
  • Check fuse ratings under the meter. 
  • Contact your DNO for specific site capacities. 
  • Review energy bills for capacity details. 

Engagement is crucial for both parties, and there are several ways to access information and contact your DNO: 

• Pre-Application Service: The PACE team handles all engagement ahead of formal applications. They can provide basic information and guidance. 
• Contact Information: Email addresses for the PACE team are available on the DNO's website. 
• Surgery Sessions: The PACE team can arrange one-on-one discussions with an engineer to talk about specific project needs. 
• Online Information: Websites often contain data on primary or grid voltages. Coverage of low-voltage supplies is being expanded. 
• Self-Serve Data: Online resources for self-service capacity information are improving. Surgery sessions are recommended for detailed, project-specific guidance. 

• Creation Process: MPANs are generated using an industry-wide system. Existing meters have MPANs (e.g., for import/export). 
• Timing: MPAN creation happens at specific construction milestones. Delays can occur if milestones are not met. 
• Temporary MPANs: These can be used to keep projects moving until permanent MPANs are issued. 
• Coordination with Supplier: Delays might involve coordination issues with suppliers. 
• Project-Specific Issues: Contact the DNO to investigate delays. Temporary MPANs can help expedite the process. 

• Schools should have a connection agreement with their DNO. 
• Capacity details are often included on energy bills or can be obtained from the energy supplier. 
• If the capacity seems inaccurate, discuss it with the design engineer, who can confirm if the cable can handle the capacity and provide costed options for adjustments. 

• For dedicated supplies, filling headroom with heat pumps is typically not an issue unless they impact other customers. 
• Heat pumps, classified as "dirty loads," may generate harmonics that affect shared networks. 
• A Stage 1 or Stage 2 network assessment may still be required, particularly for 11 KV networks, to ensure no wider impacts. 

We understand that applicants contact the DNO at different stages of their journey. If you don’t yet have all the information to request a formal quotation, we recommend you request a “Surgery” meeting via your DNO website. Those meetings are specifically designed to support your project's further development, identify any challenges your future connection might have to mitigate risks and inform you of the grid capacity before the design is completed. 

Alternatively, you can ask for a budget estimate of an assumed figure of kVa increment. Whilst this is still a valuable tool, we discourage you from basing your budget on its outcomes because, as it is an estimate, conditions can change by quite far until you have a firm quotation. 

We recommend you book a “surgery” meeting with your DNO that can address the magnitude of the works involved in your proposed design and help you identify design changes that could mitigate unsustainable costs, when possible. 

• Low voltage connections (up to 16 amps per phase, ~3.68 kW) can often be connected at no charge via a fitting inform process. 
• If reinforcement is required, costs vary based on installation size and location, as there is no cap on reinforcement costs. 

• Regulated costs: DNO charges are rigorously assessed to ensure only necessary work is included. 
• Seeking clarification: Contact the DNO for a detailed cost breakdown and explanation. 
• Cost transparency: DNOs typically provide breakdowns for transparency. 

• Assessment and Design (A&D) Fees: These cover quotation costs and are recoverable ahead of works. 
• Variation by DNO: Fee structures differ but are guided by Ofgem. 
• Cost Application: Smaller connections may not have upfront fees; for larger ones, fees (e.g., £6,000 for 132 kV) are detailed in the offer. 
• Quotation Breakdown: Offers include costs for required work, chargeable and non-chargeable items, as per Ofgem's rules. 
• Contestable vs. Non-Contestable Costs: Some work can be done by third parties, while other work must be completed by the DNO. 

• Yes, DNOs publish connection offer expenses on their websites. 
• These breakdowns include costs for different application types. Contact the DNO directly if further clarification is needed. 

Yes, DNO costs for the Scottish scheme are not eligible for Salix funding and must be covered through other mechanisms. 

• In April 2023, Ofgem revised DNO charging policies, introducing a shallow charging model. 
• Dedicated feed upgrades remain 100% chargeable. 
• Shared asset upgrades may be socialized, spreading costs among customers. 
• Timescales for shared asset upgrades typically range from 6–9 months. 

• Fees depend on the load size and specifics. 
• Quotations for loads up to 250 kVA often do not incur Connection Offer Expenses (COE) fees. 
• Published fee schedules can be found online. 

We always recommend that you keep your DNO aware of any issues that can delay the electrification of your site.  

Any changes in your project should also be shared with your DNO.  

Should the delay be on the DNO side and quoted works remain unchanged, there is no risk for the already paid works to change value. 

If a full works quote is requested, you can choose to accept and move forwards with either both contestable/ non-contestable works, or only the non-contestable works. If you accept only the non-contestable works you must employ a 3rd party to complete the contestable element – Any changes to the works accepted would require a requote.  

• Estimates vs. quotations: Estimates are less precise; quotations are binding for 90 days. 
• Planning and timing: 
  • Engage early with the DNO to align funding application timelines with quotation validity. 
  • Request extensions for quotations if funding approval is delayed. 

• Queue Management: Efforts are underway to remove stalled "ghost" projects clogging the queue. 
• Fixed Timelines: Quotation and acceptance timelines are standardised but vary slightly by DNO. 
• Transmission Constraints: Projects over 1 MW require ESO consent, adding delays. 
• Reform Efforts: Transmission reforms aim to address constraints. Contact the DNO for project-specific assistance. 

• Timelines depend on the type of upgrade: 
  • High voltage outages need a minimum of 4–6 weeks for preparation. 
  • Land rights agreements can take 4–12 months or more. 
• Early discussions with the design engineer are essential to estimate and manage lead times. 

• Yes, conducting a load assessment and applying diversity is essential. 
• This helps provide accurate data for capital expenditure estimates and ensures suitable quotations. 

• Early engagement with design engineers is critical. 
• After paying upfront fees, design engineers assist in producing comprehensive quotations. 
• For missing progress, escalate the matter through DNO channels or use services like "Ask the Expert." 

This is not mandated, however if you cannot evidence that you have engaged with the DNO at application stage, this will be added as a condition to your funding. We recommend that you obtain a quotation from the DNO for any upgrade works needed as soon as possible to avoid delays to your project completion. DNO costs can be included in your application, so it is beneficial to have a good idea of costs when you apply.  

DSO (Distribution System Operation) means that network operators look at managing the network at a local level with more control over local supply and demand. This can help to bring more low carbon flexibility services onto the network, reduce the need for reinforcement leading to lower bills, and avoid disruption by increasing performance in local networks. Distribution System Operation transition – Energy Networks Association (ENA) 

• Engage with the DNO: Share a comprehensive list of sites and requirements. 
• Assessment and Categorization: Work with the DNO to evaluate site readiness for upgrades. 
• Prioritise Based on Impact: 
  • Quick wins: Tackle sites requiring minimal work first. 
  • Critical sites: Focus on essential sites. 
• Phased Approach: Start with simpler sites and progressively address complex ones. 
• Continuous Monitoring: Regularly assess progress and adjust priorities. 

• Demand management: Demand isn’t as significant an issue as generation. The National Grid was not designed for large-scale generation, so upgrades are needed for pushing energy upstream. 
• Energy efficiency: Managing demand is generally feasible and can help reduce stress on the grid. 
• Over 50% of projects in the North do not require upgrades for new demand connections. 

• DNOs recommend proactive regional planning and data sharing to align with net-zero goals. 
• Engage with local DNOs to discuss medium- and long-term plans for projects like CHP replacements and heat pump installations. 

We always recommend that you keep your DNO aware of any changes in your project. Therefore, if you plan to install a different equipment than quoted, please make the DNO aware on time, so they can assess if any changes are needed for the connection. 

• Policy intent: Unused capacity is targeted, not planned capacity for decarbonisation. 
• Protection for future needs: Communicate your plans with the DNO to ensure your needs are considered. 
• Proactive approach: Reach out to discuss specific requirements and future use. 

• Notification and Assessment: The DNO will reassess whether the network can handle the larger system. 
• Potential Solutions: 
  • If feasible, the larger system may proceed. 
  • If upgrades are needed, restrictions may apply until works are completed. 
• G98 vs. G99 Processes: Systems above 3.68 kW per phase require G99 applications. 
• Next Steps: The DNO will guide necessary steps for compliance. 

• If DNOs cannot access the substation to complete upgrades, deadlines cannot be guaranteed. 
• Grant recipients are responsible for funding any works delayed beyond the grant end date (e.g., March 31). 

• Costs for shared network upgrades may be socialized, reducing customer expenses. 
• Early engagement allows DNOs to identify shared capacity options and offer flexibility solutions. 

Due to increased demand, there are long lead times in some areas where demand is outstripping capacity. Your local DNO will be able to provide you with more information. 

Network data is becoming more accessible via the DNOs Open Data Porta, allowing to identify where this is network constraints. 

DNOs are regulated by Ofgem which means there are strict guidelines on this. If design hasn’t been delivered then you should contact the design team responsible.

• For generation over 100 kW, DNOs must notify the electricity system operator (ESO). Larger projects (over 1 MW) require ESO assessments. 
• Constraints depend on local transmission or network upgrades, requiring further details to provide specific timelines. 

• Queue Management: Efforts to remove stalled projects are in progress. 
• Transmission Impact: Large projects require ESO approvals, causing delays. 
• Action Steps: Contact the DNO for project-specific updates and solutions. 

• Smaller applications can be faster, but larger applications requiring network reinforcement take longer: 
  • LV network upgrades: ~6 months. 
  • HV network upgrades: Up to 2 years. 
  • Wayleaves and land agreements can significantly extend timelines. 

• In constrained areas, DNOs may offer ramping agreements to incrementally increase power requirements year-over-year. 
• Flexibility solutions, such as turn-down services, are also explored for managing demand. 

Yes, the updated capacity requirement will be taken into consideration but the obligation to inform your DNO of the assets installed remains. Although you may not require an increased power connection, you will need to complete a generation connection form (please see useful links) to your DNO. Those are commonly called G98 or G99 form. 

  G98 and G99 specifically refer to different kinds of protection settings regulations that generator or storage assets must comply with to connect to the network. The protection settings are an important fail-safe mechanism that protects both the network and the asset from potential faults. So, it is important that you still get in contact with your DNO. 

• Benefits: Frees up capacity for others and can reduce standing charges. 
• Contact DNO: To adjust capacity, email [email protected]. 
• Potential risks: Additional capacity might be required later, invoking high-cost cap rules. 

• Voltage Stability Issues: High concentrations of inverters or other devices can create voltage fluctuations. 
• Network Quality: DNOs must maintain overall network quality and may require adjustments. 
• Case-Specific Decisions: Contact the DNO to address concerns and explore potential solutions. 

• Yes, contact the DNO whether you plan to export to the grid or not. 
• Even non-exporting systems can impact the network in case of a fault, necessitating updates to the connection agreement. 

• Applications must address both demand and generation aspects. 
• Private wire setups can offset demand, but peer-to-peer trading across the grid is challenging due to technical constraints. 
• Flexibility markets may allow area-specific load management. 

DNO organisations are quite similar. They all provide a quotation for power increase costs; they all require a G98 or G99 forms for microgeneration and they all require to be informed about any asset installed. 

We invite you to visit your DNO website and navigate through the available tools.

Non-Contestable works must be done by your DNO, Contestable works can be carried out by either the DNO or an IDNO.

Correct, they are.  You can ask your DNO to provide you with a list, or you might find a link in your quotation (near the contestable and non-contestable works). 

• Existing Connections: Adjustments are complex due to network reliability needs. 
• New Connections: Reallocation is easier for new connections and must consider cost efficiency. 
• Network Restructuring: Moving connections might disrupt backup feeds. 
• Case-by-Case Evaluation: Engage with the DNO for tailored advice. 

• Capacity limitations affect projects like solar farms and decarbonisation initiatives. 
• DNOs are actively upgrading infrastructure to address this, but constraints remain a challenge. 
• Early engagement and transparency with DNOs can help identify potential solutions. 

• DNOs operate dual teams for immediate (0–5 years) and long-term (>5 years) planning. 
• Data sharing and network scenarios guide investment and upgrades. 
• Queue management ensures viable projects are prioritized over stalled ones. 

As mentioned in the question, the interactivity scenario is mentioned in the DNO Offer, and usually, a link to find out what happens is shared in the quote. 

Interactivity means that a request from any other customer for connections to the same part of your Distribution System has been received after your quotation has been issued. 

We want to remind you that, until the quoted costs are paid and the quotation accepted, the capacity requested and quoted is not yours and you are now running against time and competition to get it. 

If your quotation has interactivity then the validity period will be 30days. The DNO will inform others in the load queue that they are now subject to interactivity. 

• All DNOs follow the Distribution and Connection Use of System Agreement (DCUSA) and Energy Networks Association guidance. 
• Differences are minor, mainly in application questions. Comprehensive websites and teams are available for assistance. 

This could be addressed under stakeholder engagement strategies during DNO consultations.

• Engage early and provide complete details (capacity, site plans, letters of authority). 
• Maintain communication with the design engineer for updates on lead times and requirements. 

• DNOs must treat batteries as maximum import/export under current rules. 
• National Grid is revising these regulations, but changes at the DNO level are not yet finalized.