It is estimated that there are still approximately 700 households in the Western Isles using RTS meters, and TIG is appealing to local communities to help identify those who may be affected now, especially the most vulnerable who may not have realised that they are affected.

Anyone impacted needs to urgently contact their energy supplier to arrange a replacement. RTS meters can be spotted by a black box near to the electricity meter, often labelled as ‘Radio Teleswitch’ or ‘Radio Telemeter’.

Different areas will see the service switched off for good at different times, meaning some households could lose control of their heating and hot water earlier than others if action is not taken. TIG is warning that households risk their heating and water being left either permanently on or off, which could lead to significant disruption and increased energy costs for some of the poorest households.

Kirsty MacLeod, energy advice manager for TIG, said: “It’s vital that anyone with an RTS meter gets in touch with their energy supplier now to arrange a replacement. This permanent switch-off is beginning as early as April and will continue in phases, so people really cannot wait any longer.

“We know there are still households who may not realise they have an RTS meter, or who have not acted yet. We are asking communities to look out for neighbours, friends and family who may need support. No one should be left without heating or hot water.

“If anyone is unsure what to do, TIG is here to help by supporting people to contact their supplier, understand their options and arrange appointments.”

RTS meters, introduced in the 1980s, use radio signals to switch between peak and off-peak electricity rates. As the signal is phased out, these meters will stop working properly. Further phased switch-offs of the old meters will continue through to the end of June.