The Science & Technology
of Glass
Cambridge - Monday 4th to
Wednesday 6th September 2017

Benjamin Heiz

article posted 02 August 2017

Jan 2015 - present
PhD Student
Friedrich Schiller University Jena;
Otto Schott Institute of Materials Research; D-07743 Jena

Apr 2014 - Sep 2014
Master’s Student
Robert Bosch GmbH;
Department of Corporate Research; D-70839 Stuttgart

Jul 2013 - Mar 2014
Research Assistant
Fraunhofer Institute for Mechanics of Materials IWM; Business Unit Tribology; D-79098 Freiburg im Breisgau

Switchable fluidic glass-glass laminates for real-world and large-scale application in building envelopes
Benjamin Heiz1,2*, Zhiwen Pan2, Gerhard Lautenschläger3, Lothar Wondraczek1,2

Buildings account for more than 40 % of the total European energy consumption 1) and are responsible for more than one third of Europe’s CO2 emissions. In order to realize a drastic cut in building’s energy demand and to significantly lower the CO>sub>2-emissions, key priorities have been set on energy efficient buildings and, in particular, on building skins 2).

In our presentation, we will report on a technological solution which has been developed within the research project LaWin, part of the EU’s Research and Innovation Programme Horizon-2020. We will present an ultrathin glass-glass fluidic device for real-world and large-scale application in facades and building envelopes 3).

Fig.1 - Fluidic device for large-area window and façade integration. (A) Laminate system of micro-channel glass pane and thin- sheet cover with the functional liquid flowing through the channels. (B) Schematic of the exchange of ambient heat and solar energy across an individual channel.

The device comprises of a combination of a microstructured glass pane, a thin cover glass sheet with tailored mechanical properties and a heat transfer liquid for energy storage and transport (Fig.1). With the thickness of a conventional single glass pane, the resulting laminate can be integrated into standard multiple glazing windows and facades in order to harvest or deliver thermal as well as solar energy.

Fig.2 – Mobile test lab equipped with prototype devices for testing under various climatic conditions.

Prototype devices with sizes up to ca. 1m x 1m were implemented in a mobile test lab (Fig.2) and tested under various climatic conditions to demonstrate the application as a latent heat and solar energy harvesting device. Selected results, underpinned by computational models will be presented.

Moreover, secondary functionalities were generated on part of the liquid, such as adaptive energy uptake or shading achieved by the controlled and magnetically switchable immersion of nanoparticles with tailored absorption behavior in the infrared and visible range.


1) L. Pérez-Lombard, J. Ortiz, C. Pout, Energy and Buildings 2008, 40, 394.
2) F. Pacheco-Torgal, Construction and building materials 2014, 51, 151.
3) B. P. V. Heiz, Z. Pan, G. Lautenschläger, C. Sirtl, M. Kraus, L. Wondraczek, Advanced Science 2016, 4, 3


1 Otto Schott Institute of Materials Research, University of Jena, Fraunhoferstrasse 6, 07743 Jena, Germany
2 Center for Energy and Environmental Chemistry – CEEC, University of Jena, Philosophenweg 7, 07743 Jena, Germany
3 SCHOTT Technical Glass Solutions GmbH, Otto-Schott-Strasse 13, 07745 Jena, Germany