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These are tomorrow’s smart buildings

Published May 30, 2011

According to the EU commission, buildings are responsible for 40 per cent of the total energy consumption and 36 per cent of carbon emissions. At the same time there are directives at EU level which say that there must be big reductions in the energy consumption of buildings over the next decade. This is how it will be done.

Karl Henrik Johansson
Karl Henrik Johansson, Professor of Network Engineering and Director of the KTH ACCESS Linnaeus Centre.

“You can save a big percentage of energy consumption through energy-efficient buildings. Only 1 per cent less energy consumption means huge cost savings, and this can be done without any major problems. Note that by year 2020, we must be able to save 20 per cent of buildings’ energy consumption according to the EU directives laid down. Much of that must be done through more intelligent buildings,” says Karl Henrik Johansson, Professor of Network Engineering and Director of the KTH ACCESS Linnaeus Centre.

Together with some research colleagues, including the technologist Seyed Alireza Ahmadi, he is currently developing an energy-smart conference room. IT functions such as a calendar and reservations are connected to the room. In doing so, the system that controls heating, cooling and ventilation in the room manages these factors in relation to the number of people and their personal preferences. In addition, ventilation as well as heating or cooling can be switched off during periods when no one is using the conference room.

“This can then be scaled up and applied to the entire building. This exemplifies how we can ensure energy-efficient buildings in the future,” says Karl Henrik Johansson.

However, this is just the tip of the iceberg. There are many other ways to reduce energy consumption.

“Separate climate zones around people, much like in modern cars now, are currently being tested and will soon be a reality. For example, through the use of an ID or badge with sensors, the building will know where you are. The temperature can therefore be adjusted just where you are, which is more energy efficient than adapting the temperature for a number of rooms. A lot of energy is needed today to heat empty rooms. Why let all the heat from the fire go up the chimney,” says Karl Henrik Johansson.

He adds that another way of saving energy is to locate buildings/houses close to industries to be able to use the waste heat they generate.

“It is also very expensive to route copper cables to sensors, both in terms of labour costs and for the cable itself. By using today’s wireless sensors which hardly cost anything, the price will be completely different,” says Karl Henrik Johansson.

The availability of very cheap sensors is one of the key factors for tomorrow’s energy-efficient buildings. With them, it becomes much easier and cheaper to control energy consumption. But sometimes you do not even have to measure, it is enough to scratch the surface to see how energy culprits appear with frightening clarity. As an example, Seyed Alireza Ahmadi mentions KTH’s own premises, where his research is carried out.

“When we contacted the landlord, it quickly turned out that some of the premises were being cooled during the winter, the reason was that a few meddling students had been cold and simply removed the thermostats on the radiators. This meant that the radiators were on full power and were heating the room so much that it needed to be cooled down,” says Seyed Alireza Ahmadi.

Karl Henrik Johansson adds that energy-efficient buildings means great business opportunities in a country like Sweden, which is already successful in wireless communications, IT and construction. In addition, KTH has a long tradition and considerable expertise in energy efficient buildings.

“It is interesting to see how new information and communication technology, i.e. IT, can be used to make additional improvements which were not possible just a few years ago,” says Karl Henrik Johansson.
What is the objective when it comes to heating, ventilation and cooling?

“Buildings with zero energy use are what we are aiming for,” says Karl Henrik Johansson.

For more information, contact Karl Henrik Johansson on 08-790 73 21 / kallej@ee.kth.se or Seyed Alireza Ahmadi on saahmadi@kth.se.