Living Lab smart office space
At the moment it’s all about the new Klimastuhl here. But did you know that we were working on continuously improving the innovative chair with its “heating” and “ventilation” functions long before it went into series production? For instance the Klimastuhl has been a central part of a scientific study at the Technical University of Kaiserslautern over several months, where it is being put through its paces by Prof. Hoffmann and her team. In this interview we have been invited to put some questions to Prof. Hoffmann about her project entitled “Living Lab smart office space”.
Prof. Hoffmann, you are the project leader of Living Lab smart office space at the Technical University of Kaiserslautern. Can you explain to our readers what this means?
During my time as a scientist and researcher I have conducted lab experiments under controlled conditions as well as field studies in actual buildings. When we carry out research in the “field”, in other words in real-life buildings, as scientists we struggle with the fact that it is often difficult to control the conditions on site, and that our experiments should minimise the disturbance to office operations as far as possible. On the other hand the situation in the lab, for example in a hermetically-sealed test room with full climate-control, is not representative of everyday working life, and so the findings can only be applied to actual buildings to a certain extent. Now, the Living Lab combines both approaches: it represents an actual working area as an “open space”, whilst at the same time serving as an experimentation room for a wide range of research approaches and technology developments. Anyone who uses the Living Lab as a workplace is also taking part in our studies at the same time. There are no fixed desks in place – instead there are flexible work stations based on the “clean desk” concept in which they are occupied by new users each time – which means that we receive a broad spectrum of individual feedback.
That sounds interesting. How did the idea for this approach come about?
The idea of a Living Lab catering for the theme of innovative offices and new technologies is something I brought with me from the USA, where I spent four years working and researching. In my working environment at that time they attached great importance to thinking “outside the box”, in other words beyond what is usual and normal. Then, when I was appointed Professor at the TU Kaiserslautern, the idea of the “Living Lab smart office space” came into being. I found a partner to help me implement this idea at the Deutsches Forschungszentrum für künstliche Intelligenz (DFKI; German Research Centre for Artificial Intelligence), which already had the “smart city” and “smart factory” through Living Labs. Prof. Andreas Dengel, scientific director at the DFKI in Kaiserslautern, and I share the directorship of “Living Lab smart office space”. Within the project my working group is concerned with the physical environment, in other words light, air and noise, while Prof. Dengel’s competence centre “Virtual Office of the Future” handles the questions relating to information technology.
Despite the content differentiation you work closely with Prof. Dengel from the DFKI and his team. How accurate a picture can we gain of this work?
There are many intersections where cooperation with our colleagues at the DFKI is concerned. One particular field of collaboration is sensors and software-based support for knowledge work. For example in our project with the “Embedded Intelligence” working group we use sensor mats integrated into office furniture to gather information as to how the office environment should be actively or passively adapted. This method is used to detect changes in sitting posture, and if applicable to provide information to improve the ergonomics. The lighting set-up is also customised according to user activity. But we also have access to state-of-the-art technology such as eye trackers and miniature infra-red cameras to identify the relationship between environmental conditions and cognitive performance. This ground-breaking work can only be carried out thanks to the close cooperation with the DFKI team, in particular the “Knowledge Management” working group.
How many innovative technologies have you tested over the course of time, and which ones have particularly stuck in your mind?
It isn’t easy to quantify the technologies we investigate, because the scope and nature of our research works are in some cases very different. It is better to group the technologies firstly by methods that affect the building structure, such as integrated phase change materials or smart glass products, secondly ones that affect the central plant engineering, such as optimising ventilation systems and lighting, and thirdly – more and more frequently – concepts based on decentralised strategies that ensure that the room climate is ideal.
In some research projects we mainly use simulation methods, others are based on experimental investigations, and often a combination of the two is used. Our work ranges from evaluation and optimisation in collaboration with industry partners to in-house development of technologies and products as well.
Smart glass windows, also called electrochromic glass, offer the fascinating option of only letting sunlight into the room when it’s needed and desired. At the push of a button the windows can be darkened if an excess of solar rays is unwelcome, if it becomes too hot in summer for instance, or if the sunlight causes direct or reflected glare.
One approach that is particularly interesting from a technology point involves materials that undergo phase change, e.g. from solid to liquid, and absorb and emit heat whilst this is happening. Their uses are varied: ranging from reduction of summer overheating in office buildings to heat storage for central heating purposes in the winter. We also use this type of phase change material to act as temporary storage for heat emitted as an unwanted by-product. Integration of phase change materials in office furniture is also a possibility, especially in combination with the decentralised approaches detailed above.
These decentral strategies that can be used locally to create a comfortable room climate – such as personalised ventilation, foot warmers and the Klimastuhl – harbour enormous potential since they contribute significantly towards the contentment of the building users. I think that in twenty years they will be just as central to modern office life as smartphones and other mobile devices are today.
Most of your examples come under the classification of thermal comfort. But you are also involved with the research areas of lighting and room acoustics. Could you give us a brief description of the three categories?
All three areas have one thing in common: they are usually only noticed in a negative capacity. Hardly anyone ever says “Oh, what lovely thermal conditions!” “Fantastic lighting!” or “What good acoustics!” A pleasant room climate, attractive and adequate lighting and a calm working environment are things that we expect as a matter of course from a modern office building. It isn’t until it’s too cold or hot, too light or dark, too noisy or quiet, that the concepts of thermal, visual and acoustic comfort take on a meaning. But if that happens they can reduce well-being and performance significantly.
That’s why thermal comfort is defined as the “absence of negative influences”. This refers to ambient air that is too cold or hot, draughty conditions or what is termed “radiation draught”, where cold surfaces increase body heat loss. To achieve or maintain a state of thermal comfort, the body must be able to keep its temperature within the target range that people perceive to be pleasant using the available thermoregulatory options (increased perspiration, constriction or dilation of blood vessels). However this temperature range – just like the body’s ability to thermoregulate – can vary greatly from one individual to another. That leads to the familiar problem that in the very same room climate it might be too warm for some people while others are freezing in the same conditions.
With lighting and visual comfort, spectral distribution is a key factor alongside sufficient brightness (illuminance). Today’s LEDs have a much more continuous spectrum than earlier fluorescent tubes, and they also give you the option of setting the colour temperature to the required value. This in turn – as research in recent years has been able to prove – has a direct influence on people’s activity and biorhythm. Furthermore a glare-free working environment in which glare from electric lights as well as daylight must be avoided is important for visual comfort. Good light diffusion should be taken into consideration with artificial lighting, to ensure contrast rendition is as high as possible and good legibility can be achieved.
In the field of acoustics, there can also be a wide variety of disturbance factors. Of course there needs to be adequate noise protection against external noise (traffic, aircraft etc.) and with respect to neighbouring rooms. Ventilation systems can also be grounds for acoustic discomfort because of their disruptive noise and sound transmission. However the classic problem in an open-space office is caused by colleagues making a phone call or having a meeting. The consequence of this is becoming distracted from your own work. Contrary to the initial assumption, it is frequently too quiet in rooms of this type. Admittedly of course, generally high noise levels such as those in call centres or rooms that reverberate or are over-damped do not offer a satisfactory acoustic either.
You already implied that these three areas – thermal comfort, lighting and room acoustics – exert an influence over productivity at work. Can you rank them in order of importance, and if so, what criteria do you use as a basis?
I don’t think that it’s possible to define a clear ranking. Thermal discomfort and poor room acoustics should probably go ahead of dissatisfaction with the lighting. Which category is ultimately perceived to be more disruptive is sure to depend on how each individual feels and the “severity” of the disruption, in other words the situation in that building. Equally the influence on productivity is not so much a matter of correlation with the type of discomfort, but rather with the extent of dissatisfaction: the more someone is bothered by a situation, the greater the probability that it will affect concentration on the task in hand. Conversely the same applies: the more contented people are with their environment, the higher the probability that they can fulfil their responsibilities as effectively as possible.
Prof. Hoffmann, thank you for the very informative interview. I look forward to our next discussion, in which we will look more closely at the research field of thermal comfort.