2,600+ EHV Sites. All 14 DNOs. Site-Specific Tariffs.
Extra High Voltage (22kV+) distribution tariffs from Annex 2 (import & export) with Annex 6 quarterly updates.
{
"dno": "Eastern Power Networks",
"site_id": "1001234",
"charging_year": "2025-26",
"import": {
"super_red_rate": 12.456,
"fixed_adder": 0.234,
"capacity_charge": 5.678,
"exceeded_capacity": 8.901
},
"export": {
"super_red_rate": -2.345,
"fixed_adder": 0.123,
...
}
}Understanding EDCM
What is EDCM?
EDCM applies to customers connected at 22kV and above. Unlike CDCM's 32 standard tariffs, EDCM charges are calculated individually for each site based on network location and dedicated assets.
We extract site-specific tariffs from Annex 2a (import) and Annex 2b (export), plus Annex 6 addenda which contain quarterly updates for new or amended EHV sites. When a site appears in both Annex 2 and Annex 6, the Annex 6 rates take precedence.
Why EDCM Data Matters
Site-specific accuracy
Each EHV site has unique tariffs
Revenue modelling
Critical for generator and storage economics
Bill verification
Validate invoices against published rates
Regional Coverage
All 14 Distribution Network Operators
10
Eastern
UKPN
11
East Midlands
NGED
12
London
UKPN
13
SP Manweb
SPEN
14
West Midlands
NGED
15
NPg Northeast
NPg
16
ENW
ENWL
17
Scottish Hydro
SSEN
18
SP Distribution
SPEN
19
South Eastern
UKPN
20
Southern
SSEN
21
South Wales
NGED
22
South West
NGED
23
NPg Yorkshire
NPg
Plus 19+ IDNOs covered via host DNO rate mapping.
Data Structure
9 Charge Components Per Site
Import tariffs (5 components) and export tariffs (4 components).
Import Charges
- SR
Super Red Rate
p/kWh - Peak period
- FA
Fixed Adder
p/kWh - All consumption
- CC
Capacity Charge
p/kVA/day
- EC
Exceeded Capacity
p/kVA/day - Penalty
- RP
Reactive Power
p/kVArh
Export Charges
- SR
Super Red Rate
p/kWh - Often negative (credits)
- FA
Fixed Adder
p/kWh - All exports
- CC
Capacity Charge
p/kVA/day
- EC
Exceeded Capacity
p/kVA/day - Penalty
Use Cases
Who Uses EDCM Data?
Renewable Developers
Model DUoS export credits for solar farms, wind farms, and embedded generation.
- Revenue forecasting for planning applications
- Grid connection comparisons between sites
- Business case validation for investors
Battery Storage Operators
Time-of-use network charges for arbitrage strategies and revenue stacking.
- Super Red period optimisation
- Import/export charge differentials
- Capacity charge impact analysis
Large Industrial Customers
Data centres, manufacturing plants, and EHV-connected facilities.
- Bill validation against Annexe 2 rates
- Capacity charge optimisation
- Budget forecasting for network costs
Energy Consultancies
TPIs and consultants serving large commercial clients.
- Portfolio-wide charge validation
- Client reporting and analysis
- Integration into advisory platforms
Frequently Asked Questions
Common questions about EDCM data.
EDCM (Extra High Voltage Distribution Charging Methodology) applies to customers connected at 22kV and above, while CDCM (Common Distribution Charging Methodology) applies to LV and HV connections. The key difference is that EDCM tariffs are calculated individually for each site based on network location and dedicated assets, whereas CDCM uses 32 standardised tariff categories that apply to all customers within a category.
All EDCM data is extracted from official DNO charging statements: Annex 2a (import tariffs) and Annex 2b (export tariffs) published annually, plus Annex 6 quarterly addenda for new or amended EHV sites. These are the same documents that DNOs use to invoice EHV customers. When a site appears in both Annex 2 and Annex 6, we use the Annex 6 rates as they take precedence.
Super Red is EDCM's peak charging period, which applies only during November to February, Monday to Friday, 4pm to 7pm. This is different from CDCM's year-round Red/Amber/Green time bands. Super Red rates are significantly higher than other periods to reflect peak network demand.
EDCM tariffs are updated annually when DNOs publish new Annex 2 documents (typically effective from 1 April). DNOs also publish Annex 6 quarterly addenda containing new or amended EHV site tariffs throughout the year. We check for updates weekly, and once new data is identified, extraction and validation typically takes up to a week before it appears in our database. Historical data is preserved for trend analysis.
Yes, our dataset includes tariffs from all 14 DNOs regardless of whether they use FCP (Forward Cost Pricing) or LRIC (Long Run Incremental Cost) methodology. The published tariffs are what matters for billing purposes.
Yes, EDCM data is available via our Enterprise API. Contact us to discuss access options, data licensing, and integration requirements.