The improvement of energy performance of existing buildings is a primary concern of the European Union. Energy renovation of buildings is one of the biggest challenges Europe is facing to achieve a "smart, sustainable and inclusive growth" based on efficient use of resources and a reduction in emissions of greenhouse gases between 80% and 95% by 2050 compared to 1990 levels, as part of a global commitment to limit average global warming to a less than 1.5 °C above pre-industrial levels in accordance with Paris agreement (November 2016).
In EU heating and lighting of buildings account for the largest share of energy use (42%, of which 70% is for heating) and for 35% of all greenhouse gas emissions. Sustainable energy retrofit process is already underway, but the current annual renovation rate in Europe is only 1.2-1.4%, together with a demolition rate of 0.1% per year, so it would take a considerable time before it had a significant impact. A systematic approach is needed to increase the rate of renovation to a minimum of 2-3% per year in line with EU policy targets.
Many of our buildings are, however, difficult to enhance in terms of energy thrift as building envelope insulation cannot easily be installed on walls: external application can be difficult due to the exterior finishing or shading systems (blinds); internal insulation can be difficult to apply due to geometrical complexities, and reduction in net internal floor area and height of buildings. What is indeed necessary are instead advanced solutions able to combine the energy performance with the building architectural quality and the highest livability, ensuring the achievement of the optimal cost-effective level. The latest generation of advanced materials and products for the building envelope offers considerable potential advantages both in terms of reduced intrusion and the development of practical design solutions.
Among these, phase change materials can prove particularly useful in cases of energy retrofit of existing walls in heavyweight constructions by using interior insulation systems. In this case, the application of thermal insulation panels inside the building to reduce energy loss during winter, especially in the energy upgrading of historic buildings where working with an external insulation system is not possible, often determines the exclusion of the preexisting thermal mass. This results in a quicker drop of the internal temperature during winter after turning the heating system off and in possible over-heating of the interiors during summer because of the inability to dispose of excess heat through the mass of the walls. Instead, by applying an internal insulation with a superimposed PCM lining it is possible to reduce dispersion and at the same time maintain a good thermal inertia to support the air-conditioning system. In retrofit interventions, PCM application is also viable in lightweight constructions to increase thermal mass of perimeter walls and internal partitions.
In this picture, the aim of the project is to integrate an elastomeric-PCM panel to an aerogel based insulating panel (Aeropan -
http://www.aeropan.it/en/home-gb/(öffnet in neuem Fenster)) in order to combine in an innovative single product (AEROPCM) – characterized by high performance and low thickness - both thermal resistance and heat storage capacity.
The technology breakthrough starting point is the Novurania capability to obtain an elastomeric panel incorporating non encapsulated PCM’s. This technology allows a cost reduction and improvement of technology performances. Through a process of open innovation, the main objective of the project is the industrialization and first market application of an innovative prefabricated panel. The goal is to couple a new elastomeric PCM based panel with state of art insulating panel in order to obtain improved and outstanding thermal and acoustic insulation. The main target market of the product under development is the renovation of old, and historical buildings in particular, when the application of the panel must be limited to the internal walls.
