Optimising phase change material use for energy-efficient buildings

Globally, buildings are responsible for more than 40% of total energy consumption and 25% of carbon emissions, mainly due to the high number of old housing stock with very poor insulation systems. Such buildings require a huge energy demand for heating and cooling needs, which increases their carbon footprint. By 2050 it is predicted that the number of households worldwide will grow by 67% and service sector buildings by 195%.

Developing innovative energy-efficient and low/zero-carbon materials are key areas in which the building sector can meet carbon reduction targets. A possible solution is to use phase change materials (PCMs). These can control temperature fluctuations in buildings thanks to their ability to store and release thermal energy during phase change processes (melting and freezing). However, PCMs need to be encapsulated before they can be incorporated into the built environment, to avoid leaking and incompatibilities with the construction matrix which contains them.

There are several paths to incorporate PCMs. One existing method soaks commercial lightweight aggregates (LWA) in PCM. Therefore, the amount of PCM that the LWAs can host is limited by the latter’s absorption capacity, which is low.

This PhD will explore more efficient ways to incorporate PCM into the built environment. Novel highly porous granules, made from widely available by-products, will host the PCM. The introduction of PCM into the porous granules and their coating process will be optimised. Manufactured granules containing PCM will be incorporated into cement mortars and other construction materials. The compatibility between granules and matrix, as well as their thermal performance and other key properties will be investigated. The objective is to obtain an optimal mix which will reduce energy requirements to heat and cool both new and existing buildings.

Ultimately, this research will deliver new energy efficient construction materials that can contribute to achieving the 2050 target of zero-energy and highly material efficient buildings, which is an essential target to achieve a sustainable growth worldwide.

This project is mainly experimental, therefore, applications from students with relevant laboratory experience are particularly welcome. As part of your application, please provide a one page summary of why your experience fits to the project, and why you want to do a PhD.