A grid connection agreement is the formal contract that defines the technical and commercial terms under which a site is connected to the electricity network and allowed to import (and sometimes export) power. For EV charging projects, it sets the “rules of the supply” including connection capacity, responsibilities, required protections, metering arrangements, and any constraints such as import caps or export limits.
What Is a Grid Connection Agreement?
A grid connection agreement is issued or governed by the relevant network operator, typically the DNO/DSO, and it documents the conditions for connecting a customer installation to the distribution network.
– Defines the permitted maximum import capacity (kW/kVA or fuse rating)
– Specifies whether export is allowed and under what limits
– Sets technical requirements for protection, earthing interface, and compliance at the point of connection (POC)
– Clarifies responsibilities for connection works, upgrades, access, and ongoing compliance
Why Grid Connection Agreements Matter for EV Charging
EV charging sites can add large continuous loads and may require network upgrades, so the connection agreement directly affects feasibility, timeline, and cost.
– Determines how many chargers can operate simultaneously without breaching the site limit
– Drives whether dynamic load management is required to stay within the permitted capacity
– Impacts deployment lead time if network reinforcement is needed
– Defines the operating constraints that protect grid stability and reduce grid congestion risk
– Supports future expansion planning through staged capacity increases or future load reservation
What a Grid Connection Agreement Typically Includes
Connection agreements usually cover both technical limits and administrative obligations.
– Connection capacity and maximum demand rules (import)
– Export permissions and constraints (if PV, BESS, or V2G is present)
– Metering requirements and location of utility metering
– Protection and control requirements, including any required limitation schemes
– Construction scope for connection works, timelines, and cost allocation
– Commissioning, testing, and evidence pack requirements for energization
– Ongoing obligations: access, maintenance responsibilities, and change notification rules
Import Capacity, Export Limits, and Limitation Schemes
A grid connection agreement may include strict power limits that must be enforced in operation.
– Import limit defines the maximum site draw to avoid overloading the network
– Export limit restricts how much generation can feed back into the grid
– Sites may need customer limitation schemes to ensure limits are never exceeded
– In EV charging, import limits often require dynamic load throttling to prevent trips and demand spikes
How Grid Connection Agreements Affect Project Design
Connection terms shape both electrical design and operational strategy.
– Charger count and power levels (AC vs DC) must align with permitted capacity
– Distribution architecture (switchgear, distribution boards, feeder sizing) must support the agreed maximum demand
– Load management control points must measure at the correct location (typically the POC)
– Commissioning plans must test worst-case simultaneity to prove compliance
– Expansion plans should include civil and electrical future-proofing (spare ways, duct banks, reserved footprints)
Common Pitfalls
– Assuming the site can draw “nameplate” power without confirming contractual capacity
– Designing chargers first and discovering capacity limits too late, forcing redesign
– Missing the correct measurement point for control schemes, leading to limit exceedances
– Ignoring building load peaks that coincide with charging peaks (HVAC, refrigeration, process loads)
– Expanding the site without updating or renegotiating the connection agreement
– Underestimating DNO lead times for reinforcement and commissioning sign-off
Related Glossary Terms
Grid connection
Distribution Network Operator (DNO)
Grid capacity
Grid capacity assessment
Connection offer
Grid commissioning
Grid code compliance
Dynamic load management
Dynamic export limitation
Network reinforcement