Adaptive building envelopes can provide improvements in the building energy efficiency and economics, through their capability to change their behaviour in real time according to indoor-outdoor parameters, by means of materials, components and systems. Therefore, adaptive façades can make a significant and viable contribution to meeting the EU's 2020 targets. Several different types of adaptive façade concepts have already been developed, and an increase in emerging, innovative solutions is expected for the near future. The objective of this paper is to contribute to these developments by presenting the findings of an analysis of the existing concepts and case studies and by proposing a new approach for characterization of these elements

Due to the introduction of distributed renewable energy technologies with variable resource availability, the need of flexible electrical systems is evident. In general, flexibility is achieved from the supply side and often using carbon intensive energy generators. Therefore, improving the flexibility of the electrical system by taking advantage of renewable energy generation capacities and demand response measures in buildings is of major importance for a sustainable development. Control systems to implement these demand response measures need to quantify the flexibility of the respective buildings. Having this into consideration, this paper aims at presenting a literature review on methodologies to quantify the energy flexibility of buildings