The energy supply sector is undergoing massive technological changes to reduce its greenhouse gas emissions. At the same time, the climate is progressively changing creating new challenges for energy generation, networks and demand. The Adaptation and Resilience in Energy Systems (ARIES) project aims to understand how climate change will affect the UK gas and electricity systems and in particular its 'resilience'. A resilient energy system is one that can ensure secure balance between energy supply and demand despite internal and external developments such as climate change. The physical changes in climate up to 2050 coincide with the energy sector moving towards a low-carbon future, with massive renewables targets, new smart grid infrastructure and more active demand management. As such, it is of importance to identify whether new technology and policy strategies for reducing emissions also imply changes in energy system resilience. A particular concern is that increasingly large renewable energy targets aimed at decarbonisation may create new vulnerabilities given the weather-dependency of renewable energy sources. With affordable, secure energy critical to the UK economy it is imperative to fully understand the risk posed by changing climate for the energy supply sector and its infrastructure. ARIES will develop new methods to model the impacts of climate changes on current and new energy generation technologies and understand its effect on gas and electricity demand. It will identify the impacts that these new supply and demand patterns have on energy system resilience and will suggest changes or adaptation that can 'build-in' resilience.