Two years ago, Tanya Ewing received a 'massive gas bill' for her home in Scotland, and by her own admission felt very stupid. Then she realised it wasn't her fault, it being nigh on impossible to monitor personal energy consumption. The outside meter read in cubic feet but the bill specified kilowatt hours, and to access her electricity meter she had to crouch at an angle and squint into a dark cupboard. She tried 'smart' meters but they weren't clear or smart enough, and so she decided to invent her own.

The wireless Ewgeco clearly displays in real time the amount of electricity, gas and water a home or business is using, how much that costs and how much CO2 it generates. It is effective, simple and has the potential to allow us all to get a grip on energy consumption. Inventor and panellist Trevor Baylis was bowled over not only by the idea but also by Tanya: 'You have this preconceived idea that you have to be a bloke with broken glasses to be an inventor,' he says. 'This super idea proves that's not the case.'

Tanya, meanwhile, is stunned by the positive reaction to her innovation. 'To be honest, I started working on Ewgeco when I was going through IVF,' she says. 'I said to my husband: "Well, one of them will take off."' It seems they both did - she also has a 15-month-old son.