When did you last really think about the amount of electricity your household uses? Are all your appliances A rated? Have you switched to LED lights? And what about the Energy Performance Certificate of your home? Is there room for improvement there?

For decades now, Brenda Boardman has been thinking about how to reduce the amount of energy we use in our homes. We have Brenda to thank for the rainbow-coloured energy efficiency labels with their A- G ratings that appear on new fridges, freezers, TVs, dishwashers, and washing machines. As a result of these labels and subsequent legislation, it’s no longer possible to buy an energy inefficient fridge or incandescent light bulbs. And there’s a strong incentive for manufacturers to make appliances ever more energy efficient. But the introduction of the Energy Performance Certificate for homes has been less successful.

So, is achieving carbon net zero in our homes a realistic proposition?

Brenda tells Jim Al-Khalili how much she learnt travelling the world, having just missed out on a place at university. And why in her thirties she decided to study part-time for a degree. Working and bringing up children at the same time, it took a while to complete a degree and then a PhD. But, aged 48, Brenda began her academic career working at the Environmental Change Institute in Oxford and has no regrets about the time she spent getting to know who she was an what the world was like.

Producer: Anna Buckley