Microalgae-based biofacades - Sustainable buildings and culture systems

The International Energy Agency (IEA) reported that in 2021, building operations accounted for 30% of total global energy consumption and 27% of greenhouse gas emissions. According to Ademe, 50% of energy consumption in buildings is related to heating and air conditioning. The building sector must therefore undergo a technological transformation to achieve carbon neutrality by 2050, which is a goal enshrined in the "Energy and Climate" law passed in France in 2019. The design of a building's envelope is essential in determining its heating and cooling requirements. It is this element that guarantees comfort, indoor environmental quality, and safety. Good building design, incorporating high-performance envelopes, is therefore an important lever for reducing thermal requirements while ensuring occupant comfort. It is with this in mind that microalgae biofacades have been developed.

The goal is to create an "active" facade that can produce biomass that can be used for industrial purposes, while reducing the environmental footprint of the host building by, for example, reducing the energy consumption associated with the thermal comfort of the building's occupants, i.e., reducing heat gain in summer and heat loss in winter, by creating synergy through the pooling of building materials and the exchange of matter and energy between the building and the biofacade.

This article presents the concept of microalgae biofacades, their expected performance, and their potential for developing more sustainable buildings and industrial microalgae cultivation systems.

A glossary of terms used can be found at the end of the article.