Smart meters have the potential to not only provide information to individual householders about their energy consumption, but to identify patterns of usage across the entire energy system. At Nesta, we have been analysing smart meter data to uncover information about energy consumption habits, and how household appliances, physical property characteristics and demographic factors influence energy usage - as this can help develop energy-saving initiatives. In this talk we will present the data science techniques we used, such as clustering, present our results as well as discuss how we translate them to a non-data science audience, and share learnings of conducting data science work in a secure data lab to allow for analysis of sensitive and confidential data.