Based on ENA EREC G100 guidance

Is there capacity on the supply? Find out in 60 seconds.

Adding EV chargers, a heat pump, battery storage or solar? Enter your own figures for an instant green, amber or red result based on EREC G100. The full £49 PDF report is usually emailed within a few minutes.

Start Free Assessment

Free online calculation • £49 for the full PDF report, no VAT charged • No subscription

Built for the professionals planning the connection

Electrical Contractors

Assess proposed loads and establish ALM feasibility before submitting formal connection applications.

Property Managers

Evaluate EV, heat-pump, solar PV, and BESS integrations across commercial and industrial portfolios.

Commercial Landlords

Calculate theoretical headroom before committing capital to physical infrastructure upgrades.

Reduce the risk of DNO delays and unnecessary network upgrades.

Establish your curtailment logic and fail-safe strategy before submitting your ENA application.

The Old Way
  • ✗ Submit an application without a documented ALM calculation.
  • ✗ Risk lengthy DNO engineering approval delays.
  • ✗ Application queried because the demand figures don't add up.
  • ✗ Find out late that the site may need a supply upgrade.
The Gridcap Way
  • ✓ Enter existing site demand and the EV chargers, heat pumps or batteries you plan to add.
  • ✓ Calculate each phase and the load-management reduction needed.
  • ✓ Get a feasibility report based on EREC G100 and the ENA connection criteria.
  • ✓ Submit it to the DNO as supporting information, with installer verification and sign-off.

Example Gridcap Results

Our algorithm models your proposed load against the applicable assessment criteria to produce a clear calculated result.

*The figures below are illustrative examples based on a standard 160A commercial CT supply.

Green — No ALM Required

ALM Operating Limit152.0 A
Unmanaged Peak138.0 A
Remaining Operating Margin14.0 A

Within the ALM operating limit on your inputs, without load management. Check the ENA criteria to see whether you can notify the DNO or need to apply first.

Amber — ALM Required

ALM Operating Limit152.0 A
Unmanaged Peak188.0 A
Required ALM Reduction36.0 A

Above the ALM operating limit (set from the agreed import capacity where known, otherwise the fuse rating). The unmanaged peak is checked against 145% of the fuse rating on each phase and is within it here (the fuse-protection test only; the DNO also assesses thermal and voltage limits). Potentially acceptable with an Active Load Management (ALM) scheme meeting EREC G100, subject to DNO assessment.

Red — Likely Capacity Increase

ALM Operating Limit152.0 A
Unmanaged Peak350.0 A
Capacity Deficit198.0 A

Load management alone isn't enough on these figures. The site likely needs a capacity increase; the DNO will confirm and may offer alternatives.

Run your site assessment

Check your site's available capacity and ALM feasibility below.

Don't know your DNO or network operator? Find it here →

ALM Feasibility Assessment

For projects using Active Load Management, DNO applications may require technical information demonstrating how site demand will be managed within the agreed import limit.

See exactly what your
£49 assessment produces

A PDF feasibility report with supply-capacity, existing-demand and ALM calculations, the EREC G100 requirements your scheme must meet, and installer verification and sign-off.

£49, no VAT charged.

Download the full 6-page sample report (PDF)

No email needed. The sample uses an illustrative commercial office with two 7.4 kW workplace chargers (AMBER result).

Page 2 of the Gridcap sample report: executive summary and feasibility result (AMBER, ALM required)
Sample report: page 2 of 6

Frequently Asked Questions

What information do I need to complete an assessment?
For the free check you need the cut-out fuse rating (or, for CT-metered supplies, the agreed import capacity or supply fuse rating), the agreed import capacity if you know it, the existing peak demand (measured amps per phase, or a rough kW estimate), and the kW ratings for your proposed EV chargers, heat pump, battery and solar PV. The site postcode and 13-digit MPAN are only needed when you order the £49 report. Your MPAN is on your electricity bill, usually labelled Supply Number or MPAN.
What does the £49 report include?
You receive a PDF feasibility report containing a document control summary, the existing demand baseline, the unmanaged peak calculation for each phase, the likely DNO route, the load-management approach and the EREC G100 requirements the scheme must meet (if needed), and an installer sign-off page. The report costs £49, no VAT charged.
What is Active Load Management (ALM)?
ALM dynamically monitors your building's total electrical draw in real-time via a CT clamp at the connection point (the customer side of the meter). If the total load approaches the ALM operating limit (95% of the agreed import capacity or fuse rating), the ALM hardware automatically throttles power to your EV chargers (heat pumps and batteries are counted at full rating), potentially avoiding the need for a physical supply upgrade.
Which DNOs does Gridcap support?
Gridcap's method follows ENA guidance (including EREC G100 and the ENA EV charge point and heat pump process), which applies to the distribution network operators in Great Britain (UK Power Networks, SSEN, National Grid Electricity Distribution (NGED), SP Energy Networks, Northern Powergrid and SP Electricity North West) and to independent network operators (IDNOs). It is not intended for Northern Ireland.
Does this guarantee DNO approval?
No. Gridcap provides a feasibility calculation and supporting information for your DNO application. While the report assesses the theoretical feasibility of your ALM strategy, final approval always remains at the discretion of the regional DNO and requires correct physical installation by a competent person.
Is Gridcap for commercial or domestic installations?
Gridcap is built primarily for commercial electrical projects (three-phase supplies, several EV chargers, heat pumps or batteries). However, it is fully capable of assessing single-phase applications requiring ALM logic.
I'm adding solar or a battery. Is a G100 scheme enough?
No. Solar PV and battery storage are generation, so they need their own notification or application to the DNO under EREC G98 or EREC G99. G98 covers type-tested equipment of 16 A per phase or less in total, including any generation already on site, and you notify the DNO within 28 days of commissioning. Anything larger, or not type tested, falls under G99 and needs approval before it's connected. A G100 scheme limits how much power the site imports or exports at the connection point, but it doesn't replace that notification or application. The free check and the report show which route is likely to apply.