Citizens Advice published its response to the Department for Energy Security and Net Zero (DESNZ) consultation on Tariff Interoperability on 19 January 2026, supporting the proposals in principle while raising concerns about one element of their scope1.
The consultation sits under the Smart Secure Electricity Systems (SSES) Programme, which covers the technical and regulatory groundwork for smart energy services. Tariff interoperability means standardising the way tariff pricing data is formatted and shared, so that a household's appliances and apps can read and act on the prices from any supplier. Citizens Advice said standardising tariff pricing data is "an important step in enabling consumer-led flexibility and helping households and small businesses benefit from smart energy services"1.
The organisation set out what it expects the change to deliver for consumers:
"Interoperability should make it easier for consumers to compare tariffs, switch supplier and make the most of energy smart appliances."
It also backed publishing the list of registered Tariff Interoperability Users, the third parties authorised to access tariff data, saying this "will improve transparency and help consumers verify third parties before granting access to their tariff data"1.
The main objection concerns the proposed exemption threshold for non-domestic suppliers. Citizens Advice said this "could exclude many small non-domestic consumers from the benefits of tariff interoperability and limit effective switching"1. The response does not state what the threshold is, and the level at which DESNZ proposes to set it has not been reported in the material published alongside the response.
| Position | Citizens Advice view |
|---|---|
| Standardised tariff pricing data | Supported |
| Public register of Tariff Interoperability Users | Supported |
| Non-domestic supplier exemption threshold | Concern raised over scope |
Why it matters for households
Tariff interoperability is the plumbing behind time-of-use pricing. Without a common format for tariff data, a household's smart appliances, electric vehicle charger or home battery can only respond to prices from the supplier whose system they were built to work with. Standardised data is intended to break that link, so a household can change supplier or move to a different tariff without losing the automation that shifts consumption to cheaper periods.
For a home with solar panels, a battery or a heat pump, that flexibility is where much of the saving sits, because the value comes from running appliances when prices are low rather than at a flat rate. The practical effect of interoperability is that the choice of supplier stops determining whether those devices can be used this way.
The transparency point matters for a different reason. Granting a third party access to tariff data means handing over details of when a household uses electricity and what it pays. A public register of approved users gives households a way to check who they are dealing with before agreeing. Complaints and redress routes for energy consumers are handled through established processes involving Citizens Advice, Consumer Scotland and the Consumer Council alongside the Ombudsman.
The exemption threshold is the part with the least direct read-across to domestic households, since it concerns non-domestic suppliers and their small business customers. Citizens Advice framed its overall position as support for the direction of travel, asking government to ensure implementation "promotes inclusion, transparency and effective consumer protection across both domestic and small non-domestic markets"1.
What happens next
DESNZ has not published a response to the consultation or a timetable for implementation, and no date for either has been reported. The SSES Programme sits within the department's wider remit on home energy policy.
Sources1 cited
- Citizens Advice response to DESNZ’s Tariff Interoperability Consultation - Citizens Advice, citizensadvice.org.uk