Britain is building one national store of every household's half-hourly electricity data, and is now consulting on who is let in

Ofgem opened a consultation on 14 September 2026 on the legal basis and governance of the Smart Data Repository, the national store that will hold the half-hourly electricity consumption data of British households. Responses are due by 19 October 2026. The document is titled 'Smart Data Repository: policy rationale and proposed governance framework', and it is addressed to code bodies, suppliers, consumer groups and data users.

The repository itself is not new policy. Ofgem directed Elexon to build it as part of the Market-wide Half-Hourly Settlement programme, so that consumption data collected for settlement could be stored, managed and then made available to third parties where the consumer consents. What the consultation is doing is retrofitting that instruction with a legal foundation. Ofgem proposes to amend Energy System Operator Licence Condition E1, which covers operation of the Balancing and Settlement Code, and Supply Licence Condition 47, which sets out when a supplier may share smart meter consumption data. Access by third parties is to run through RECCo's Consumer Consent Solution rather than through a separate consent mechanism of the repository's own.

The reason this is worth attention has little to do with settlement and a great deal to do with who can act on a household's behalf. A virtual power plant operator, a flexibility aggregator, a tariff-switching service and an independent auditor of a supplier's bill all need the same thing: the half-hourly series for one meter point, with the householder's permission. Until now that series has been scattered across suppliers and partially held on the meter itself, which made third party access slow, inconsistent and in practice dependent on the incumbent supplier's cooperation. A single repository fixes that, and in fixing it creates a single place where the answer to 'who may see this' is decided once, for everyone.

That is the structural point. Britain has chosen to make the sensing layer that enables edge participation into a centralised asset, and then to govern access to it through two licence conditions. Those two conditions now carry more weight for a household's ability to monetise its own flexibility than most tariff decisions do. If the consent route is broad, cheap and durable across a supplier switch, the repository is an enabling piece of public infrastructure. If it is narrow, or chargeable, or resets whenever a household changes supplier, then the data has simply moved from one set of incumbents to a single one.

Several things the consultation page does not settle. It states no retention period, which matters because the value of a consumption history to an aggregator rises with its length. It does not say whether a household can retrieve its own history directly or only authorise someone else to retrieve it. It does not say whether third party access is charged. [NEEDS DATA: retention period, go-live date, access charges] The trade body Association of Meter Operators describes the repository as holding data beyond the thirteen months a smart meter retains, which is the most consequential single claim in circulation about it, and which Ofgem's own page does not make.

There is also an unresolved separation-of-duties question. Elexon will run the repository and already runs the Balancing and Settlement Code. The consultation is the place to say what keeps the settlement use of this data apart from its commercial use, and anyone who cares about that has until 19 October to say so.