Getting your business connected to the UK grid costs far more than most assume. DNO approvals, reinforcement charges, and delays that balloon timelines are standard—yet most businesses stumble through this process uninformed. Knowing G99 requirements, smart metering standards, and TNUoS charges before you apply separates those who pay thousands extra from those who don’t. One overlooked decision at the start determines whether your connection runs smoothly or derails your budget entirely.
How to Get DNO Approval: G99 Requirements Explained
If you’re planning to connect renewable energy systems—like solar panels, battery storage, or wind turbines—to the electricity grid, you’ll need approval from your local Distribution Network Operator (DNO) through a process called G99.
Connect renewable energy to the grid? You’ll need G99 approval from your local Distribution Network Operator first.
This formal request guarantees your system won’t destabilise the grid or cause power quality issues.
Your DNO checks whether the local grid can handle the extra power you’re generating without creating voltage fluctuations or frequency problems that might damage equipment. Our energy monitoring tools can help track your system’s performance after approval to ensure ongoing compliance. Real-time reporting provides immediate insights into your system’s performance and grid interaction.
You’ll need G99 approval if your solar panels exceed 3.68kW on single-phase connections or 11kW on three-phase systems.
Battery storage systems that export power also require approval.
Installation must wait for DNO approval before energising systems covered by G99.
The entire process takes 4-8 weeks for standard applications, though complex projects may need 3-6 months.
Smart Metering and Export Standards for Grid-Connected Systems
Smart metres record half-hourly data, giving you real-time visibility into your energy patterns and export volumes.
If your system exceeds 30 kW, you’ll require a dedicated export metre to measure electricity sold back accurately.
From December 2026, half-hourly metering becomes mandatory for all business premises. The Government’s push to achieve 80% smart metre coverage across UK homes and businesses by end of 2026 reflects the critical importance of digital metering infrastructure for the energy transition. This real-time data insights enable you to identify consumption patterns and optimisation opportunities specific to your operations. Working with a transparent energy broker can help you leverage these insights to negotiate better commercial rates aligned with your usage profiles.
This capability enables you to access Smart Export Guarantee schemes and fine-tune time-of-use tariffs, ultimately lowering your bills.
The Data Communications Company manages your network connectivity, ensuring transparent data transmission throughout the settlement process.
Why Grid Reinforcement Delays (and Costs) Your Connection
While smart metres and export standards give you real-time visibility into what you’re generating and selling back to the grid, getting your system connected in the first place presents a much bigger challenge.
Here’s the reality: the UK’s grid infrastructure wasn’t designed for distributed renewable projects like yours. When you apply for connection, the network operator must assess whether local cables and transformers can handle your output. If they can’t—and increasingly, they can’t—expensive reinforcements become necessary. These upgrades require strategic energy management to ensure your project aligns with broader grid infrastructure planning and regulatory requirements.
These upgrades take years and cost millions of pounds. You’re stuck waiting whilst contractors plan, fund, and complete work. Over 700 GW of projects currently queue for assessments, with some facing 15-year delays. Energy data integration throughout your project lifecycle can accelerate approvals and improve coordination with network operators. Dormant or speculative applications are also blocking viable projects by consuming available capacity before serious schemes can progress.
Your project fundamentally underwrites infrastructure upgrades that benefit everyone downstream, but you bear the timeline risk and financial burden.
Connection Windows: When to Schedule Your Installation
The timing of your electricity connection depends entirely on your site’s complexity and capacity needs. Small single-phase connections typically take 2–6 weeks, whilst three-phase setups for most SMEs require 6–12 weeks. If you’re operating an industrial facility or data centre needing high-voltage connections, you’re looking at 12–20+ weeks minimum.
Things move faster when you’ve got simple projects with existing infrastructure already in place—expect around 6–12 weeks total for these. However, complex developments involving groundwork, new infrastructure, and third-party approvals stretch the timeline significantly, potentially reaching 6–12 months or longer. DNO reinforcement work adds even more time on top of your initial connection offer. Your Distribution Network Operator will assess whether the local grid can support your proposed connection before issuing a formal connection offer that confirms approval and outlines any reinforcement requirements.
This is why planning ahead really matters. Try to schedule your installations during quieter periods in your operations, when downtime won’t impact your business as heavily. Consider integrating energy efficiency solutions to optimise your power consumption once your connection is live, which can help offset the costs of your new electricity infrastructure. Real-time monitoring and maintenance tools enable you to track energy consumption effectively after installation and identify further optimisation opportunities. Getting organised early prevents bottlenecks down the line and keeps everything running smoothly whilst the grid upgrades take place around you.
The 6–12 Month Planning Window Before Contract Renewal
Beyond the connection installation itself, you’ve got a critical window to manage: the 6–12 months leading up to your contract renewal.
This timeline isn’t arbitrary—it’s when major infrastructure work happens. Complex projects involving underground cables, substations, or transformer installation need this extended period for planning and execution. Aligning your infrastructure plans with ISO standards ensures your project meets regulatory compliance requirements throughout this phase. Engaging with energy procurement specialists during this period can help you optimise your energy requirements and identify cost reduction opportunities before finalising your new contract.
Early consultation with your Distribution Network Operator (DNO) and local authorities prevents regulatory delays during this window. You’ll navigate planning permission requirements, secure third-party consents if needed, and finalise design agreements. Engaging a Certified Electrician or Electrical Engineer early ensures your internal wiring design and compliance requirements are coordinated with the DNO’s network connection plans.
Starting conversations now means you’re not scrambling when renewal dates arrive. By mapping your infrastructure needs today, you’re positioning your business for smoother shifts and better negotiating power when contract discussions begin.
TNUoS Charges: What You’ll Pay After Connection
Once you’ve connected to the transmission network, you’ll face an ongoing cost that’s separate from what you pay for the actual electricity you use: TNUoS charges.
These charges recover costs for building and maintaining Great Britain’s high-voltage transmission infrastructure. The National Energy System Operator manages TNUoS collection on behalf of transmission owners, with Ofgem providing regulatory oversight.
Your specific charge depends on your maximum import capacity and consumption classification. Here’s what you might expect to pay:
| User Type | Daily Charge | Annual Impact |
|---|---|---|
| Domestic | £0.14 | ~£51 |
| Low consumption | £0.15 | ~£55 |
| Medium consumption | £0.76 | ~£277 |
| High consumption | £2.07+ | £755+ |
It’s worth noting that from April 2026, you should anticipate a 60% increase in these charges. On your overall electricity bill, TNUoS typically represents about 10% of the total cost. You’ll see it charged through your supplier’s invoice, either rolled into your standing charge or shown as a separate line item.
Total Grid Connection Costs: What to Budget
When you’re connecting to the grid, you’ll face several upfront costs that go beyond just the monthly bill—DNO approval and any reinforcement work needed to handle your electricity demand, metering infrastructure that lets you track and export power, and the ongoing TNUoS network charges that keep the system running.
These costs vary dramatically depending on your location, connection capacity, and whether you’re exporting power back to the grid, so grasping each component helps you budget accurately.
Getting quotes from your local DNO early in the process gives you the clearest picture of what you’ll actually spend to get connected.
DNO Approval And Reinforcement Costs
Getting your commercial electricity connection approved isn’t just about filling out paperwork—you’ll also need to understand the costs the Distribution Network Operator (DNO) might charge you, which can vary significantly depending on your situation.
G98 notifications won’t cost you anything upfront since they’re approved immediately. G99 applications, on the other hand, typically run between £300 and £750, though Scottish Power often charges higher fees than other DNOs.
Once you’ve sorted the application side, you might face network study expenses ranging from £500 to £2,000. If your connection requires reinforcement work—upgrading cables, substations, or trenching—you should expect anything from £1,000 to £50,000 or more.
The positive aspect here is that you can often source contestable works through Independent Connections Providers, which could save you considerable money. Understanding these different cost layers helps you budget accurately and prevents unwelcome surprises later on.
TNUoS Charges And Network Fees
Beyond the upfront DNO approval and reinforcement costs, you’ll encounter another substantial layer of charges: TNUoS fees, which stand for Transmission Network Use of System. These charges recover costs for maintaining GB’s high-voltage transmission network, representing roughly 10% of your electricity bill.
What you’re actually paying for breaks down into several key areas. Daily fixed charges range from £0.15 to £317.60 depending on your consumption level, so higher usage means steeper baseline costs. Your location matters significantly too—location-based tariffs vary markedly by your zone across GB’s 27 generation zones, which means where your business sits geographically directly impacts what you’ll pay.
The timing of these charges adds another consideration. Annual increases are rising over 60% year-on-year in 2026, potentially adding tens of thousands to your annual bill. Most suppliers bundle these pass-through costs within your standing charges, so they won’t always appear as separate line items on your invoice.
Understanding these inevitable expenses helps you budget accurately and plan smarter energy strategies for your business’s growth. Since TNUoS charges form such a significant portion of your overall energy costs, getting ahead of these increases becomes crucial for your financial planning.
Metering And Export Infrastructure Investment
As your business grows and you consider exporting power back to the grid—whether through solar panels, combined heat and power (CHP) systems, or other generation sources—you’ll need to invest in metering infrastructure that tracks both what you’re consuming and what you’re producing.
Half-hourly metres come with substantially higher TNUoS charges, ranging from £8 to £20 daily depending on your region. These costs reflect the network’s investment in modernising infrastructure to handle two-way electricity flows. You’re effectively paying for the capability to feed energy back into the system safely.
Beyond metering, export capacity investments vary based on your generation size and location. Network operators may require upgrades to handle your export volumes.
When you understand these infrastructure costs upfront, you can budget accurately and determine whether your renewable investment actually delivers genuine financial returns for your business. This insight is crucial before you commit significant capital to generation equipment, as the hidden costs of grid connection and export can substantially impact your overall project economics.
