Smart meter rollout and ‘half hourly settlement’ reschedules will mean it takes longer for consumers to get the benefits of their investment in the programmes and slow innovation on Net Zero. Plans to move electricity consumers to meter reading on a half-hourly basis, which would give them the option to access tariffs offering different prices at different times, have been delayed by at least a year.
Such tariffs reward consumer flexibility and can help lower the country’s overall power bill and carbon emissions if they help take advantage of excess renewable energy or avoid starting up old, expensive fossil plant for short periods. They may be similar to longstanding ‘Economy seven’ arrangements that may offer cheaper power overnight, provide cheap power at specific times to electric vehicle or heat pump owners, reward consumers who shift usage out of peak periods, or take advantage of other new tariffs. In order to benefit, customers have to have a smart meter that registers usage in half-hourly periods. Currently customers are allocated to one of a small number of ‘profile classes’ reflecting typically – but not real – usage over the day.
At the moment customers have be individually changed to ‘real’ half-hourly usage data if they want to use so-called ‘smart’ tariffs. Market-wide half hourly settlement (MHHS) would make it available for every consumer.

Half-hourly settlement delayed
The revised market-wide half hourly settlement (MHHS) plan will see the date at which consumers start to receive real-usage bills delayed from October 2025 to at least December 2026 (with the latter date potentially delayed by up to six months).
In a discussion of the change, programme managers said the revised migration period would now span 18 months instead of a year, but would see customers moved over in tranches, so some consumers would get benefits quickly.
The discussion said a review now was “consistent with the original intention set out by Ofgem in August 2021”. It said, “In reality, the current MHHS Transition Timetable has been viewed as unrealistic and unachievable since mid-2022 and lacks widespread buy-in across the industry programme participants” and that had been worsened by ‘challenging industry conditions’.
It said a revised plan, baselined with industry support, “is now urgent” to set out a credible approach. The programme has been operating under an ‘interim plan’ for over six months and it needs a programme with ‘buy in’ from the companies involved. It said “‘No change’ is not a viable option” because participants cannot be held to account to account as there is no credible measure to meaningfully and legitimately gauge progress.
The discussion warned that “A continued lack of a credible plan means that Government’s and Ofgem’s expectations as to when other Net Zero Programmes may deliver, are unmanaged and may not be reasonable. This could seriously impact their strategic planning.”

Smart meter rollout delayed
The delay comes as the smart meter rollout has reached half of consumers and the National Audit Office (NAO) says the benefits – which often take the form of smart tariffs – are just beginning to be realised.
In a new report the NAO said that “The smart meters that have been installed are beginning to demonstrate benefits, including potentially helping to achieve power sector decarbonisation” such as the Demand Flexibility Service put in place by the National Grid Electricity System Operator (ESO) over winter 2022/23, which enabled consumers to receive an incentive for shifting their consumption to help reduce peak demand. But its hope, expressed in the report, that “Flexibility services and time-of-use tariffs are likely to become more widespread after April 2025, when Ofgem expects industry to have commenced migration to new half-hourly settlement arrangements across the retail electricity market” will now be delayed by the MHHS ‘replan’.
Other benefits are beginning to emerge. DESNZ has reported that some distribution network operators have been able to identify network faults earlier since 2021, when smart meter coverage reached around 25–30%. As at January 2023, four of the six electricity networks had confirmed to DESNZ they are now able to verify service connectivity using smart meters via their call centres. However, network operators told NAO in January 2023 “that their ability to fully benefit from smart meter data was limited by the lower than expected smart meter coverage, and some reported they could not always reliably access the volume of data they need from the central platform service”.
In any case, the NAO said that although the 50% level had been reached, the rollout was very variable and some areas have less than 10% smart meters. Most suppliers had failed to meet their installation targets. Large suppliers with targets reported installing 3.7 million smart meters in homes and small businesses against their combined target of nearly five million in 2022. NAO said they could go faster: “Both Ofgem and DESNZ believe that suppliers are not meeting existing demand for smart meters and that there is scope for suppliers to improve their performance.”
The NAO said that for its part “DESNZ does not have an overall view on where all the meters have been installed, and whether there are areas which are seeing more technical issues than others.”