Grid connection is where many farm solar projects stall — and where specialist agricultural knowledge makes the critical difference. Rural electrical infrastructure was designed decades ago for importing electricity, not exporting it. Connecting a 50-200kW solar system to a rural three-phase supply requires careful engineering, proper DNO (Distribution Network Operator) applications, and often network reinforcement negotiations.
Every solar installation over 16A per phase (approximately 3.68kW on single phase, 11kW on three phase) requires a G99 application to the local DNO. For agricultural installations, this typically means liaising with UKPN, National Grid Electricity Distribution (formerly WPD), SSEN, SP Energy Networks, Northern Powergrid or NIE Networks. Each DNO has different application processes, timescales, and technical requirements. Our team has established working relationships with all UK DNOs and manages the entire application process.
G98 vs G99 — which route is my farm?
The threshold is 16A per phase. Below it, a system connects under G98 (connect-and-notify — fast). Above it, a system needs a full G99 application and a connection offer before it can energise. Virtually every commercial farm system (20kW and up) is G99.
The six UK Distribution Network Operators
| DNO | Region covered | Typical G99 assessment |
|---|---|---|
| UK Power Networks (UKPN) | East, South East, London | 6–10 weeks |
| National Grid (NGED) | South West, Midlands, S Wales | 8–12 weeks |
| SSEN | Southern England, N Scotland | 8–12 weeks |
| SP Energy Networks | Central/S Scotland, N Wales, Merseyside | 8–12 weeks |
| Northern Powergrid | North East, Yorkshire | 6–10 weeks |
| NIE Networks | Northern Ireland | 8–12 weeks |
Export capacity, limitation and reinforcement
Rural substations frequently have limited export capacity. When a network study reveals export constraints, we negotiate export limitation (G100) agreements on your behalf — allowing your system to generate and self-consume at full capacity while limiting exports to the agreed level. For farms with high self-consumption (dairy, poultry, processing), export limitation rarely affects savings because most electricity is used on-site. Where reinforcement is unavoidable, we run a budget enquiry first so you can weigh the cost against a limited-export or battery-backed design.
Three-phase upgrades
Three-phase supply upgrades are common on larger farm installations. Many older farmsteads have single-phase supplies inadequate for 50kW+ solar systems. We coordinate supply upgrades with the DNO, managing costs and timescales to avoid project delays. For very remote farms, we assess whether the grid connection cost makes on-site storage with limited export more economically viable.
Smart Export Guarantee included
Smart Export Guarantee (SEG) registration is handled as part of our service. MCS certification — required for SEG eligibility — is included with every installation. We advise on the best SEG tariff based on your export profile and system size, with current rates ranging from 4-15p per kWh depending on provider and tariff structure. See our cost guide for how export income factors into payback, and the grants guide for FETF and AIA.
Grid connection — frequently asked questions
Do I need a G99 application for farm solar?
Any system over 16A per phase (≈3.68kW single-phase, ≈11kW three-phase) needs a G99 application to your DNO before it can connect and export. Smaller systems use the simpler G98 "connect and notify" route. Almost every commercial farm solar system (20kW+) is G99. We prepare and submit the full application for you.
How long does a DNO grid connection take?
A G98 notification is near-instant. A standard G99 application takes 6–12 weeks for the DNO to assess. Where the network needs reinforcement, a connection offer can take 3–6 months and the works longer. We submit early — usually in week 4–5 of the project — so the DNO clock runs in parallel with survey, design and grant paperwork.
What is export limitation and will it cost me savings?
If a rural substation has limited spare capacity, the DNO may approve your system only with an export limitation device (G100) that caps how much you push to the grid. It does not cap generation or self-consumption — so for dairy, poultry, pig and processing farms that use most of their power on-site, export limitation rarely dents savings. It often unlocks a connection that would otherwise be refused or hugely expensive.
How much does a farm solar grid connection cost?
A straightforward G99 connection with spare network capacity typically costs £1,000–£5,000 in DNO fees. Where a three-phase upgrade or local reinforcement is needed, costs rise to £10,000–£40,000+. We run a budget enquiry before you commit so there are no surprises, and design around export limitation where it avoids costly reinforcement.
Do you handle the Smart Export Guarantee registration?
Yes. SEG registration is included in our service, and the MCS certificate required for SEG eligibility comes with every installation. We advise on the best SEG tariff for your export profile — current rates run 4–15p/kWh depending on supplier.