Nearly a million households are facing their cheap night-time electricity rates being cut off next month unless they have a smart meter installed.
Many homes could even lose access to heating and hot water if they don’t agree to having a smart meter.
This comes as the technology that powers the older Economy 7 and 10 meters will be switched off from March 31, leaving many owners of these devices facing an uncertain future.
Economy 7 and 10 tariffs offer cheaper nightly electricity rates and are popular with homes that want to save money by running appliances such as washing machines and dishwashers at night, or by using storage heaters at night.
To get these rates, homes must have one of three types of meters.
These households need a modern smart meter, a slightly older meter with a digital or mechanical clock or a meter that runs on technology from the 1980s, called Radio Teleswitch (RTS).
Update: Following publication of this story, a last-minute extension to the deadline for replacing Economy 7 meters has been revealed to This is Money, delaying the switch-off of RTS until sometime in 2025
Petering meters: Old Economy 7 meters like this may no longer work properly in a few weeks
The problem affects these older RTS meters, which piggyback on BBC Radio 4’s longwave channel to communicate with energy companies. Energy companies use RTS to switch a meter between peak and off-peak rates.
According to figures from energy regulator Ofgem, there are around 900,000 active RTS meters in Britain.
The contract between the BBC and energy companies to manage the RTS system expires on March 31, although This is Money understands that last-minute talks are underway to try to extend this deadline, perhaps until 2025.
But if the RTS service is turned off, households are faced with their meters not working properly and potentially losing their hot water and heating.
Many energy companies are now contacting their RTS meter customers and urging them to switch to a smart meter.
An email from EDF to an RTS meter customer states: ‘Once this service is discontinued, your meter may lose functionality and off-peak times may change.
‘This can also lead to the loss of important functions such as heating and hot water.
‘You could also see higher costs because if the RTS service ends, your off-peak hours may no longer be picked up.
‘By upgrading your meter, you can continue to benefit from your off-peak hours, without needing the radio signal.’
The customer said: ‘EDF bombarded me with emails a few months ago saying that my meter will no longer receive the signal (for Economy 7 switching) in 2024, meaning my heating and hot water will probably not work , so I will need a smart meter well in advance due to demand.
“So the previous intimidation against the government insisting that I have one has now turned into what can be classified as veiled threats.”
A similar email to an Octopus customer stated: ‘The technology that switches your meter from peak to off-peak prices will end in March 2024.
‘After the Radio Teleswitch Service (RTS) ends, your meter timings may not work as expected.
‘There is a simple solution: we have to replace your meter. Book your smart meter installation on a day that suits you, we will take care of the rest.’
But many households do not want a smart meter, or cannot have one installed due to connectivity problems.
Some readers have told This is Money that their smart meter bills are incorrect, or that they feel bullied into buying one.
Homes that do not want to lose their RTS meter can, in theory, keep it. Having a smart meter installed is not mandatory, unless your old one is dangerous.
But keeping an RTS meter means you’ll lose access to the cheap night-time electricity of Economy 7 and 10 tariffs in a few weeks, unless the deadline is extended.
Instead, households with RTS meters will likely switch to an alternative energy deal without off-peak rates.
An Ofgem spokesperson said: ‘Ofgem expects suppliers to ensure that appropriate metering arrangements are in place for their consumers.
‘This includes arranging the replacement and modernization of RTS measuring equipment before any end date and communicating clearly with consumers about this.’
Economy 7 and 10 energy deals are also compatible with mechanical meters that do not use radio to communicate with energy companies. Instead, they rely on a clock-like timer to know when peak and off-peak hours start and end.
Households with these mechanical meters are not affected by the current March 31 deadline for disabling the RTS service.
Many Economy 7 and 10 tariffs are also popular with electric vehicle (EV) owners, who want cheaper electricity when charging their car overnight.
However, many EV owners will be affected by the end of the RTS service, as most EV-specific energy agreements already require homes to have a smart meter to sign up.
Some links in this article may be affiliate links. If you click on it, we may earn a small commission. That helps us fund This Is Money and keep it free to use. We do not write articles to promote products. We do not allow a commercial relationship to compromise our editorial independence.