The energy revolution underway in glass extensions

Christian Wiegel at Solurlux discusses glass as a construction material in the context of a research project on the development of ‘energy self-sufficient’ glass extensions.

Constructions made of glass have their own special charm. As a trained architect and engineer, I am thinking first of all about architectural aesthetic appeal and I use the word archi- tecture here to encompass the language of form, design and tectonics.

For more than 15 years the driving tension field of my work has been ‘atmos- pheres, tectonics and energies. Glass as a construction material has an unexpectedly large influence on the energy characteristics of a building, while the climate of a particu- lar location also plays its role. A building’s facade which is made predominantly of glass can make a significant part of the solar radiation effective as useful energy in the building.

Admittedly, in the summer, solar energy may provide more heat than the user wishes and in the winter, a comparatively large proportion of the heating energy of the building is lost via the glass facade into the environment. During my professional career, I have prepared calculations and plans for many buildings to show how, over a course of a year, buildings can lose the least minimum energy through the facade. The perceptible comfort of the interior for the user is the key factor when building a glass extension.

Before the research project of the past three to four years could get fully underway there were a few things which had to be prepared and clarified including the instal- lation of the research glass extension on the Solarlux site in 2013.

As transparent extensions are glass struc- tures, research poses a great many interesting questions including: How much energy can be provided by the sun alone? How does the location affect it? How much energy do we need for heating in winter? What savings in heating energy for a residential house can extensions provide and how much energy does an extension itself need?

The topic and questions are exciting as they have to be looked at in a holistic manner. In my view, glass extensions offer the potential to make a silent contribution to the energy revolution. The tightened requirements on the overall energy balance of buildings due to the energy savings regulations and legislation on renewable energy etc, should be sufficient cause to consider utilising solar architecture.

The intention of my research work has been to develop a completely new glass extensions concept in which the majority
of the heating energy required can be generated independently by the extension. The aim is also to increase the number of hours per day that can be spent in a maximum feel-good climate within the extension. This can be reached by the technological development of glass facades which, in the future, through using functional glass in facades, energy will be created and used immediately or saved in a seasonal store, depending on the temperature.

The main aim is to operate the glass extension solely self-sufficiently with regenerative energy and the secondary aim, dependent on location, is to also supply the house itself with the energy generated by the glass extension.

In our day-to-day existence, we all need to think about ways of saving energy. And governments need to play their part by setting new standards. In my opinion Europe is approaching the matter very intensively, and luckily others are gradually following. We have known for some time that glass extensions are a component of reliable solar architecture but now we are leading the way proactively as glass extensions can make a significant contribution to the environment. The energy saving potential of glass extensions is clear.

Christian Wiegel is research project manager, Solarlux