Introducing Janique Hupperetz, scientist at Brightlands Materials Center

Janique Hupperetz is a junior scientist in our Sustainable Buildings team. She has a bachelor’s degree in Chemical Engineering and a master’s degree in Biobased Materials. The project she currently works on is called Sunovate. In this project thermochromic pigments are developed that can be applied in e.g. polymer films.

Six questions for Janique Hupperetz:

Can you tell us something about the projects that you are working on?
The Sunovate project is an Interreg project and it has two main goals. One of them is to produce and demonstrate functional films which can be implemented in building-integrated photovoltaic (BIPV) panels, where IR blocking pigments are used in polyolefin elastomer encapsulants to laminate solar panels. These pigmented encapsulants will make sure that all IR-light that is not used for electricity generation will be blocked. In this way it will prevent the heating of the BIPV panels, hereby increasing power output and lifetime of the panels.

The other part of the project, in which I am mainly involved, is about the research and development of functional polymer films in windows, the so-called safety glass units. These polymer films contain thermochromic pigments which have the ability to either block or transmit infrared light of the sun, based on the temperature of the glass. These films will be used to laminate two glass plates. The implementation of these so-called ‘smart windows’ will make sure that in winter the infrared-light of the sun will be transmitted, thereby contributing to the heating of the building. While in summer, the IR-light will be blocked, and it will keep your house cool without the need of air-conditioning.

Can you tell us more about the relation to pigments?
In Sunovate we are developing thermochromic nanosized pigments, which can be implemented in polymer films. These functional films can be used for the lamination of windows (e.g. safety glass units). Over the past few months, we have developed a method to produce high-quality thermochromic nano-pigments on pilot-scale. It is really important that the pigments have sizes below 100 nm. Larger particles can interfere with the visible light, thereby changing the optical properties in the visible part (e.g. haze). The functional polymer films that we have developed have very low haze levels and a really high visible transmission, making them suitable for window applications. The functional films will be used to laminate 1 by 1 meter sized windows, which will be installed in test buildings at SolarBEAT in Eindhoven (NL) and at EnergyVille in Genk (BE). The demonstrators will be monitored and compared to standard laminated glass for one year while recording the most important parameters, such as performance, temperature and environmental stability.

In the building industry the use of energy saving is a hot topic. How does your research contributes to this topic?
Over the next 35 years, more than 230 billion m2 of buildings will be constructed or renovated in cities worldwide. Therefore, it is important that the goal of the European Union of an energy and climate-neutral built environment by 2050 is taken into consideration.

The total energy consumption can be divided into three major economic sectors: buildings, transportation and industry. Amongst those, the building sector contributes about one third of total energy consumption and CO2 emission, with more than 50% of this energy being used for Heating, Ventilation and Air-Conditioning (HVAC) systems. Furthermore, a major factor for the energy loss in buildings are windows. In Europe, the buildings are mostly equipped with dated, inefficient glazing, leading to more than 40% heat loss through windows. Therefore, there is a huge energy savings potential for exchanging current windows with energy-efficient glazing.

There are already some static energy-efficient glazing systems on the market. They are either developed to regulate the solar heat gain of windows through blocking of infrared light, or to reduce radiator heat loss through the window. There are also systems that combines both, but, due to the reduced solar heat gain of these glazing systems, there is still room for improvement in climates with increased heating demands. Especially in climate regions with hot summers and cold winters, dynamic systems are required, that are able to change their properties depending on the requirements of the building and the weather conditions. Therefore, our Sustainable Buildings program is focusing on the research and development of glazing systems that can switch their solar heat gain depending on an external stimulus, such as thermochromics.

Are there energy-efficient glazing systems on the market that can reduce energy savings?

Yes. these dynamic systems make sure that, depending on the glass its temperature, the infrared-light of the sun is either transmitted or blocked, while the visible light is not affected. This will lead to a reduced air-conditioning and radiator usage. Simulation studies have proven that this system could lead to a reduction of 4.5 Mt of CO2 annually when the whole Dutch Built Environment would implement these dynamic glazing systems. Besides, these smart windows can save 638 euros annually based on an average Dutch household (172 m2 , 25% window façade).

“The government is striving for an energy and climate-neutral built environment. Our technology fits this goal perfectly”


Can your program help glass companies or building constructors?
Our Sustainable Buildings program has close contacts with glass companies and building constructors. Glass companies are always looking for innovative technologies that increase the energy savings of windows. Our thermochromic technology can expand the market of products that glass companies can offer. Building constructors have to adapt to the regulations of the government. The government is striving for an energy and climate-neutral built environment. Our technology fits this goal perfectly. Not only have the smart windows developed by BMC’s Sustainable Buildings program an energy savings potential up to 22%, but it also has a return of investment of approx. 7 years, thereby making it very interesting for house owners, glass companies and building constructors.

“It would be amazing if I can be part of the progress for energy-neutral buildings all over the world”


Which innovation do you hope to work for in the future?
Each and every program of the Brightlands Materials Center is focusing on sustainable and circular developments. In the future, I would like to be even more involved in the research and development of innovations that contribute towards a biobased/circular economy. I am convinced that there is still a lot to gain in the energy savings of e.g. the built environment. Therefore, it would be amazing if I can be part of the progress for energy-neutral buildings all over the world. Within the Sustainable Buildings program, we are now ready to upscale our technology to produce smart windows and I am very excited to be a part of this process.

More information about our Sustainable Buildings program.