Energy production from algal photosynthesis isn’t new of course, but with fifteen apartments, The BIQ building is the world’s first full-scale bioreactive façade. BIQ, which stands for Bio Intelligent Quotient, uses heat recovery as its main source of energy, capturing energy not used in photosynthesis from the bioreactor solution. The façade of this building located in Hamburg, Germany, also acts as a natural thermostat: thick algae growth in the summer keeps the sunlight out.
The two south-facing facades are covered in a shell of bioreactors, clear containers that create a controlled environment for an algae farm. Exposed to sunlight, the algae photosynthesize, absorbing CO2 as they grow. Nutrients and CO2 are circulated through the bioreactors to encourage growth. Periodically, the algae are collected and fermented in a nearby biomass plant, then burned to produce electricity.
The technology was created by SSC Strategic Science Consult, which developed the building in collaboration with Arup, a design, engineering and consultancy firm; Colt International, a project management company; and Otto Wulff, a Hamburg construction firm.
Subject to further tests, SSC claim a conversion efficiency (the amount of light hitting the façade converted to energy) of 10 per cent for biogas and 38 per cent for heat—almost 50 per cent in total. That compares to a typical efficiency of about 15 per cent for PV solar. The heat and power from the bioreactors are also supplemented by rooftop solar panels and an underground heat storage system. The building’s creators claim it can meet 100 per cent of its energy needs.
The main barrier to further adoption of the technology is price. Of the €5 million invested in the project by the German government and IBA Hamburg, an international building exhibition, over €1.3 million financed the bioreactors. However, Martin Kerner, Managing Director of SSC, is confident the technology can become competitive. “We need standardization of hardware production to reduce costs,” he says.
Demonstrating the efficiency of the algae building could not only prove a source of sustainable energy production, it could also shape future cities, according to Jan Wurm, Europe Research Leader for Arup. “If we can demonstrate microalgae facades, we can transform the urban environment [and provide] architects with a new source of inspiration.”
By Fionán O’Muircheartaigh. This article originally appeared in Green Futures, the leading magazine on environmental solutions and sustainable futures published by Forum for the Future.