Grid Connection Consultancy — From Application to Energisation

G99 application — what's actually in the package

A G99 application is not a form. It's an engineering package that has to satisfy the DNO that your proposed generation is safe to connect, won't compromise the network, and includes the protection settings to disconnect under fault. KMM produces:

• Single-line diagram showing the proposed generation, protection devices, isolators and connection point.
• Inverter manufacturer certification evidence for G99 compliance.
• Export configuration — whether you're applying for full capacity export, partial export, G100 export-limited operation, or zero export.
• Protection settings package matched to the local network impedance.
• Site-specific design rather than generic templates — DNOs reject template-style applications.

G100 export limitation

G100 is the certification that an inverter is type-tested to limit export below its rated capacity. This is increasingly required as DNO capacity tightens — many feeders can't accept full export from a typical commercial PV system but can accept the system if export is limited to (say) 80% of inverter rating. KMM specifies G100-certified inverter families and submits the limitation parameters as part of the G99 package.

Grid Upgrade Support via Crown Utilities partnership

For projects where DNO reinforcement is needed — typically because the local feeder, transformer or substation can't accommodate the proposed generation — KMM partners with Crown Utilities for the upgrade scope. Crown Utilities is an experienced UK utility infrastructure contractor. The named KMM offer here is 'Grid Upgrade Support' — we manage the DNO relationship, the upgrade scope, the contractor coordination and the reinforcement contribution funding case for the client.

Cluster and private wire arrangements

Where multiple buildings on a single landowner's site need power, a private wire arrangement (low-voltage cable between buildings, under common ownership, not crossing third-party land) avoids the DNO reinforcement that a public-network connection would trigger. This is particularly powerful on:

• Large agricultural sites with farmhouse, parlour, grain store and machinery shed under one ownership.
• Industrial estates under single landlord ownership where on-site generation can serve multiple tenants via private wire.
• Mixed-use developments where solar on one roof can serve adjacent commercial space without grid involvement.

'Off-grid' — what it actually means

'Off-grid' is one of the most misused terms in UK solar. In practice, off-grid means the site has zero connection to the public DNO network and runs entirely on on-site generation, storage and back-up. This is technically achievable but almost never financially or operationally optimal for UK commercial or domestic sites. What clients usually mean when they say 'off-grid' is one of: islanded operation during grid outage, low / zero export, energy independence (self-consumption maximisation), or battery-backed essential load.

KMM clarifies which of these you actually want. For most clients, 'islanded with battery backup' or 'grid-connected with high self-consumption' is what they actually need — not true off-grid. We design accordingly.