Digital technology has the potential to radically reshape the way we generate, trade and consume energy. Over the past decade, the incorporation of information and communications technology into the energy system has emerged as a significant driver of change in the sector but the pace and scale of that change is likely to increase dramatically over the decades to come. This Briefing Paper investigates the key technologies that underpin the digitisation of energy and examines their potential impacts. The overarching objective of the paper is to understand the effects new technologies will have on the current energy system, the new challenges they will pose, and the policies and regulatory measures which will assist in making them a success. Specifically, this paper considers four technological areas of digitalisation: big data; machine learning and AI; the Internet of things; and distributed ledger technology, often referred to as blockchain.