Distribution Use of System (DUoS) charges are levied by Distribution Network Operators (DNOs) for use of the distribution network. They materially affect battery revenues at low- and high-voltage sites.
DUoS fees are charged for importing and exporting on the distribution network
Distribution Use of System (DUoS) charges are fees levied by Distribution Network Operators (DNOs) for the use of their distribution networks.
DUoS charges can result in batteries either paying for, or being paid for, connection to the grid. The effect varies by region and voltage, similar to other network charges. Further detail on DUoS and battery revenues is available in this Modo Energy research article.
DUoS costs depend on location, voltage, and time-of-use behaviour
DUoS charges affect all users connected to a distribution network, both generators and demand. The charges depend on:
- Location: Each DNO region has different charges. The GSP regions and constraints page shows how to determine the correct DNO region for a site.
- Voltage: Lower connection voltages typically incur higher unit charges because they use more of the distribution network. Low voltage (LV) rates are generally higher than high voltage (HV) rates, which are higher than extremely high voltage (EHV) rates.
- Site connection: Sites with larger connection capacities pay higher charges.
- Behaviour: Some tariff elements are time-of-use. The DUoS ‘red band’ typically sits between 16:00 and 19:00 on weekdays — consuming energy during these hours can cost 10 times more than at other times of day.
DUoS tariffs combine fixed, capacity, and time-of-use unit charges
- Fixed charges: Incurred regardless of the amount of electricity consumed or generated. Charged in [p/MPAN/day].
- Capacity charges: Based on the maximum capacity agreed for the site. Charged in [p/KVA/day]
- Unit charges across different time-of-use bands: Vary with the amount of electricity imported or exported. LV and HV sites have green, amber, and red pricing bands that depend on the time of day. The red band is typically between 16:00 and 19:00 on weekdays; the green band is overnight. EHV sites can have a site-specific super red band, which usually applys in the weekday evening window during the winter.
Site-specific DUoS rates can be added to a custom forecast run
Custom forecast runs can include DUoS charges by uploading a grid charges CSV to the forecast run form on the terminal. The interactive tool below builds that file from published DNO Schedules of Charge for LV and HV sites.
- Select the DNO region (see the location page if unsure).
- Select voltage (LV or HV) and the relevant charging year. This price will be used throughput the foreast horizon.
- Enter the site import and export limits in MW. These are used to calculate capacity-based fixed charges (assuming 1 kVA ≈ 1 kW, power factor 1).
- Click Download data for your forecast run to save the CSV.
- Upload the CSV when configuring a custom run on the terminal.
Both import and export charge values in the CSV should be positive. Import charges increase the effective cost of charging; export charges increase the effective value of discharging.
The CSV follows the grid charges input format used by the dispatch model. Fixed daily charges - including capacity charges - are included as a separate row and appear in revenue outputs rather than affecting dispatch decisions.
EHV tariffs are site-specific and are not available through this tool. Weekend band timings can differ from weekday patterns — always verify the downloaded file against the DNO’s published Schedule of Charges.
For assistance with site-specific inputs, contact your Modo Energy account manager.