Algae: constructions are going green

Algues-les-constructions-se-mettent-au-végétal Algorigin

Micro algae have recognized properties in many new areas. From lighting to heating homes through air pollution control, the manufacturing of biofuel, plastics or even cosmetics, algae has many surprises in store for us! We take advantage of this file to reveal all their secrets to you.

MICROALGAE FOR HEATING

Imagine a building where 100% of its heating needs and 50% of its hot water would be provided by spirulina . Well, this building exists. Built in 2013 in Hamburg, it has, on its ^200m2 facade, tanks containing spirulina, photobioreactors.

Thanks to the composition of the culture medium (nutrients and CO₂) and the exposure to the sun of the facade, the micro algae develop significantly and carry out their growth activity in complete tranquility. photosynthesis. The heat released by their growth as well as that of the sun is then transported to a heat exchanger in the basement of the building to heat domestic and sanitary water. The hot water thus recovered makes it possible to cover 100% of the building's domestic heating needs and 50% of the current hot water. The remaining 50% is produced using a heat pump. However, microalgae are living organisms sensitive to temperatures that are too low or too high. A microalgae protection system is therefore planned to protect them from extreme climatic conditions.

Unfortunately, this type of building is currently very expensive to construct but, in the long term, the engineers in charge of this type of project hope to be able to reduce their cost.

PAINT IN 'GREEN'

Let's stay in the building sector with a Breton company which uses micro algae, these natural and renewable components, to produce paint.

These algae-based products contribute to the air quality of homes thanks to their low emissions of volatile organic compounds. These VOCs are toxic compounds present at less than 1 g/liter in algae-based paint compared to values of up to 100 g/liter for traditional paints.

This innovation derived from renewable resources which highlights respect for the environment and short circuits has received numerous French and European distinctions.

PLASTIC WITHOUT PLASTIC

Plastic is one of the wastes that takes the longest to decompose when thrown into nature. For example, a PET bottle takes 100 to 1000 years to disappear, even creating a 7^th continent of plastic in the middle of the Pacific. This pile of waste represents a real environmental problem and contributes to the impoverishment of marine biodiversity.

Thanks to mechanical and thermal treatments, the manufacture of plastic based on algae grown without pesticides or fertilizers and consuming very little water is in fact possible. Objects resulting from this technology are biodegradable. After 12 weeks in the ground, the object disappears playing a role of natural fertilizer. As a bonus, this material is easier to work with than traditional plastic pellets and does not require investing in special equipment. The uses for this type of plastic are endless, from eyeglass frames to flower pots to reusable cups, algae can already invade your home.

In the near future, algae could help improve the energy performance of your home. They will also be part of your daily life by helping to limit pollution of the ambient air while limiting the ecological impact of the manufacturing and recycling of plastics.

See you soon to discover the possibilities for using algae in the urban landscape and in the field of cosmetics.