Thursday, 07 February 2013 09:05

Living buildings: Taking green to the next level

WEBSITE: A zero-energy building under construction in Germany is set to provide the first real-life test for a new facade system that uses live micro-algae to provide shade and generate renewable energy at the same time.

Forward-thinking people who live in glass houses should use a bio-adaptive facade and grow algae, writes Karien Slabbert.

Buildings powered by solar and wind energy might have become common-place, while biodiesel produced from algae is a well-known concept. However, the latest technology has raised the green bar by using algae as natural energy vectors. Splitterwerk Architects of Graz, Austria, have set a new international standard by designing the world’s first algae-powered building in Germany, dubbed the BIQ.
Covered with a bio-adaptive facade of micro-algae, the unique building has been designed for the International Building Exhibition (IBE) in Hamburg, and is set to be completed in March this year. The project is collaboration between Spitterwerk Architects, Strategic Science Consult of Germany, ARUP and Colt International.

How it works

The bio-adaptive facade consists of bio-reactor louvres filled with approximately 200m² of live micro-algae. Algae in the bio-reactor facades grow faster in bright sunlight to provide more shade. The facade concept is designed so that algae in the bio-reactor facades grow faster in bright sunlight to provide more internal shading. The bio-reactors not only produce biomass that can subsequently be harvested, but they also capture solar thermal heat – both energy sources can be used to power the building.
In practice, this means that photosynthesis is driving a dynamic response to the amount of solar shading required, while the micro-algae growing in the glass louvres provide a clean source of renewable energy. Jan Wurm, Europe research leader at ARUP, said:  “While generating renewable energy and providing shading to keep the inside of the building cooler on sunny days, this system also creates an interesting appearance that many architects and building owners will like. It is a valuable method for generating renewable energy, whilst providing effective solar shading which itself keeps cooling loads down.”

Clean green

Wurm added: “To use bio-chemical processes for adaptive shading is a really innovative and sustainable solution, so it is great to see it being tested in a real-life scenario.” 
This zero-energy building will be the first real-life test for the new facade system and will allow scientists, engineers and builders the opportunity to assess the full potential of the system as a green alternative.

Cultivating micro-algae

According to Splitterwerk Architects, photobioreactors (PBR) is an established technology that is used to cultivate micro-algae. In principle, PBR generate biomass as a renewable energy resource.
Transparent glass and polymer containers that encapsulate a cavity of approximately 20mm in which water and algae circulate. The veins interconnect the leaves to a single cycle; the biomass in form of algae is harvested at central location in the plant room of the basement, while the carbon is absorbed by every leaf.
The biomass is storable solar energy – it can be used as a fuel or can be converted into electrical energy. Micro-algae grow up to 30 times faster than other macro-organisms and are therefore ideal for providing biomass. Furthermore, micro-algae generate heat, just like a solar collector. Through heat exchange, the heat can be stored in a mass storage at the foundation of the tower.

Full acknowledgement and thanks are given to www.polizeros.com, www.kurzweilai.net, http://blog.coltinfo.co.uk and www.ecochunk.com for providing the information to write this article.

GIL Africa 2017