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YERA (Young Energy Reviewers Association), a group of students who review public articles that focus on energy, interviewed Lieve Helsen about cities of the future.


These are Lieve's thoughts following the interview, entitled, "What do the cities of the future look like?"


"Some weeks are more turbulent than others … last week was one of these …

We have seen substantial technological progress with respect to energy systems in buildings. The classical oil-fired boiler combined with radiators is no longer the standard, more sustainable (mainly low-exergy and renewable and residual energy sources (R2ES) based) technologies and combinations of technologies are installed today. Consequently system complexity increases and attention should be paid to make all devices effectively work smoothly together. System integration is key! The use of data and anticipating future disturbances or changing boundary conditions may increase system gains, in all aspects. Model predictive control (MPC) is one way to realize this, and will be one of the next milestones that contribute to the optimization of energy systems in the built environment.

I see a strong parallel with team work. Also the collaboration between human beings becomes more complex (among others due to the multitude of tasks we have, the speed of communication, the availability of data and social media) and attention needs to be paid to make all individuals effectively work smoothly together. To generate good results and to create impact it is not enough that intelligent individuals work very hard. The team members should work together towards a common goal, tackling  as a strongly connected team the disturbances faced in an atmosphere of open communication. People engagement is key! Again, interpreting signals (the use of data) and anticipating future issues may increase the global team (system) gains, in all aspects. Here, I do not believe that MPC is the solution. The solution lies in all of us. Let’s engage to connect, to take care and to lift the whole team to a higher level.

I count on all of you ;-)"

Lieve Helsen

You can read the interview in Dutch here and below the English translation:

"What do the cities of the future look like?"

An interview with Prof. Lieve Helsen, 11th Feb 2019

Thanks to YERA - Simon Nagels (Chair), Wim Van Uytven (Representative Research), Louis Brouyaux  (Representative Research) 


More and more citizens and politicians agree that we must evolve towards a more ecological, low-carbon and healthier society. But where exactly do we have to go? How do we get there? What are the technical and political stumbling blocks? YERA decided to ask Lieve Helsen, professor at the KU Leuven and head of the research group "Thermal Systems Simulation - The SySi".   


It is clear that we are facing monumental challenges. Where to start? 

More than half of all people on earth live in a city. Cities therefore play an important role in the impact that we as humans have on our planet. Moreover, living in a city is often less healthy. We must strive for cities that use their resources in a smart way and where it is also pleasant to live. This includes everything: transport, food, energy, open space and air quality.


How do you build such a smart city? 

In my opinion, it is important to think in a comprehensive way. For example, by only minimising energy use, you will achieve a very energy efficient city, but if that city scores poorly at any other point, we are nowhere. We must look for solutions that offer an answer to multiple problems at the same time.


The laying of vegetable gardens on roofs is a nice and simple example here. This can help against flooding in the event of heavy rain, heat waves due to the natural cooling effect of the plants, for the logistics associated with supplying food to the city, and also improving air quality. In addition to thinking comprehensively, you also have to think collectively. This means that you optimise the global utility of the city or neighbourhood instead of each house separately. For example, if you install a thermal network, you work more globally and this can, for example, reduce costs because you can get a surplus of heat from your neighbour to your home. There is so much more that can be imagined collectively. Unfortunately, we as Belgians are not that strong at that, but I am convinced that we can change that.


Subsequently, the participation of the citizen in obtaining solutions is crucial. This gives you broader support and the citizens themselves benefit, and then I think more broadly than purely economically: it is difficult to stick a price on clean air and sufficient greenery.    


We clearly still have a long way to go. How can we make the change faster? 

In Flanders and Belgium I see some major stumbling blocks that hamper a rapid transition to, for example, a cleaner energy supply. I will focus on heat pumps (see: what is a heat pump?) because it has enormous potential for decarbonisation and for improving air quality in cities. Moreover, as a member of the Steering Group of the Flemish Heat Pump Platform and the European Heat Pump Association, I have a broad view of this technology.


[What is a heat pump?  A heat pump uses electricity to upgrade cheap heat from a colder environment (the outside air, groundwater or ground) to a higher temperature. Where natural gas and heating oil are finite and carbon-containing energy sources, the electricity for a heat pump can be renewable. Moreover, you can store hot water more cheaply than electricity itself. As a result, heat pumps have great potential to efficiently use variable renewable energy sources].


First, there is a lack of a clear policy. In our current political system, direction is still being changed too often. As long as there is no clarity about where we are going, there will be no major investments. Another obstacle to breaking through heat pumps is the low gas price. Belgium has much less taxes to pay on gas than on electricity. The electricity / gas price ratio in Belgium is the highest in the whole of Europe. I find this incorrect, because gas is a fossil fuel that we also import from abroad. An ever-increasing fraction of our electricity is renewable and produced locally. We therefore argue for a tax shift.


In addition, the difference in purchase price between a gas boiler and a heat pump is also a problem. But look at how strongly the prices of solar panels have fallen due to mass production. This can certainly also happen for heat pumps. The longer we wait to send a clear signal that we want to go all out for heat pumps, the more we will lose our technological lead to countries like China. Then we will be in a situation where everyone will purchase heat pumps from China, while the technology has largely been developed here. Moreover, I already notice that many good Flemish installers go to the Netherlands, where stricter rules already apply to the heating system in new-build homes. By the time the heat pump breaks through en masse, we have a shortage of installers. These are two examples of how our economy can fall victim to a lack of a clear vision. 


That all doesn't sound so promising ... 

Despite these obstacles, I am optimistic about the future. I notice that more and more citizens and politicians understand that the transition to renewable energy sources is a necessity. And I know that we have the technologies to make the transition to, for example, largely renewable heating. Moreover, every day I see from my research how much room there is left to improve the implementation of these new technologies.


What kind of research do you carry out? 

My research group is called "The Sysi’s". This stands for "thermal systems simulations". We focus on system integration. The central idea of ​​our approach is that many interesting renewable energy technologies already exist, but together they perform sub-optimally. Big savings can be achieved by sizing and controlling PV panels, solar collectors, heat pumps, thermal networks, combined heat and power, energy storage, etc. We apply this in two areas: on the one hand the energetic valorization of waste and on the other hand the built environment.


In the latter case, we work at both city and building level. At city level we try to optimise energy conversion and storage, in interaction with heat and electricity networks, both in terms of design and control. At the building level we focus on Model Predictive Control (MPC). This is a control method that is based on both physical models of devices and buildings themselves, and on the prediction of external factors such as weather conditions. This makes it possible to anticipate what is to come, and is necessary to allow multiple devices in a hybrid system to work together optimally. We have been working on this optimization for 10 years through simulations and we are convinced that these smart control techniques have great potential. So it's time to put theory into practice. 


How do you intend to tackle that?

We are currently working on several pilot projects for MPC implementation in buildings, in particular an office of Infrax in Dilbeek and an elderly care home of Mintus in Bruges. With these demos cases we want to prove that MPC can achieve real energy savings. This should succeed despite the uncertainties that are not included in the simulations, but that do exist in reality, such as errors in the weather forecast and unprecedented user behaviour. This year a masters thesis student is also looking at a wing of our own mechanical engineering building.


If this proves to be a success, control companies will not only show interest in our algorithms but also take action. There are also opportunities to start spin-offs: the founder of SynaptiQ Building within the company 3E is one of my former doctoral students and is already implementing MPC in practice. We have recently also secured KU Leuven and VLAIO funding to shape a spin-off around a new approach within MPC. With our demos, we hope to find more and more entry into practice and to effectively market MPC via the spin-off.


What can we do ourselves (e.g. in our daily habits) to contribute to the future sustainable energy system? 

We can do a lot, we realise too little. Especially by cultivating good habits, you can achieve a lot with little effort. Switch off the light if it is not used. Close the radiator when the window is open. Eat less meat, reducing livestock emissions and releasing land for renewable energy. These habits are all simple and with "leading by example" you get others across the bridge. 


In addition, by raising awareness and informing friends and family, by thinking long-term and collectively, by reflecting on what your impact is, you can achieve a great deal. 


Finally, we must realise that there are many other pollutants besides CO2 that require attention (just walk around on a cold winter's day, then you can smell the emissions from the wood stoves) and that the climate problem is a global problem. So we have to get the whole world into the green transition. That might be the hardest part.



[Illus. Envida Heat Sources Community Energy illustration showing how multiple energy sources can be connected to Guelph's community-wide network, and provide cost competitive energy for heating, cooling, hot water and electricity]