A knight in shining armour led a protest against smart meters being installed in homes amid fears they cause harmful radiation.

Mike Mitcham, who runs the UK’s Stop Smart Meters campaign, stood in front of Wimbledon’s Centre Court shopping centre in his genuine suit of armour, while supporters handed leaflets to passersby.

By 2019, the Government wants every home in Britain to have smart energy meters to help residents control and manage their electricity use.

A mass rollout to replace current meters is expected to start in 2014.

The campaigners claim the meters, which communicate by radio or mobile phone signals, will be like having a “phone mast in your house” and they cause one person in 20 to suffer insomnia, nausea, tinnitus and headaches.

Last year, the World Health Organisation classified wireless radiation as “possibly carcinogenic”, but smart meters give out significantly less radiation than mobile phones, satellite TVs and microwaves.