Academician Jarek Kurnitski: Estonia is at the top in the field of energy efficiency

In light of recent competition, academician Jarek Kurnitski reveals that the state valued the energy efficiency excellence centre he manages for both high research quality and the positive impact on Estonia and society in general. "We don't come from nowhere. The previous centre of excellence for knowledge-based construction was already working on these topics in the energy efficiency of buildings and indoor climate. We have extensive experience and history in the areas of technical systems, indoor climate and energy, and we have also published many publications," Kurnitski lists the main strengths. Besides, we mustn’t overlook how much TalTech has already contributed to the development of near-zero energy buildings and the development of related energy efficiency calculation methodologies and technology, as well as energy efficiency regulations, which are of a very high standard in Estonia.

According to Kurnitski, the reason behind Estonia's success is also the fact that performance-based requirements for buildings, i.e. based on total energy use, were already established in 2008. "This means that the constructor of the building only has to fulfil one requirement – to achieve the limit value of the energy efficiency, which is the total weighted energy use in kilowatt hours per square metre per year," says Kurnitski.

The construction design team and the builder, however, are free to decide how to technically achieve this requirement. This situation calls for smart and efficient solutions, in which the euro is the best consultant. Developers quickly understood this and the established methodological and legal framework led to rapid development, as five years later buildings with the same construction cost were better by two energy label classes. "So actually, in terms of energy efficiency, digital twins have been made for buildings in Estonia since 2008. The verification of compliance with the required energy efficiency figure is carried out with a dynamic simulation calculation, which is very flexible in taking into account all manner of new and innovative solutions," says Kurnitski

In Estonia, we must use validated energy simulation software, it is a commercial software whose developers are interested in ensuring that it meets the latest technology standards. Kurnitski notes that in many countries, development has been hindered by the fact that the required national calculation methodologies or rudimentary tools used by the state are not keeping up with development. "Our system has been very market-based and liberal and the Estonian state also has the courage to establish energy efficiency requirements at a cost-optimal level, as the price of energy is actually quite high here."

Although Estonian developers and builders tend to complain that it is easier to build apartment buildings and other houses in Finland and Sweden because the requirements are more relaxed there, this may not remain the case for long, says Kurnitski. Estonia has been able to demonstrate a faster rate of development, which is now being felt. "In the longer term, Finland and Sweden will catch up with us at a slightly slower pace and making these changes will also take longer in larger countries," explains the researcher.

In any case, we have already made the energy transition from class C to class A when it comes to constructing new buildings in Estonia. "The transition to near-zero energy buildings in 2019−2020 was surprisingly successful and painless," says Kurnitski, who adds that today's buildings have a very high level of energy efficiency, as well as excellent construction quality and this has given us a very good scientific reputation.

"Estonia knows how to build energy-efficient buildings with a good indoor climate," says Kurnitski, hinting that this was evident in the evaluations of the centre of excellence as well. Although the centre of excellence deals with everything that is needed locally, it does not call itself an Estonian centre of excellence, but a centre of excellence for energy efficiency. "We want to be at the absolute top of the world, however, we limit ourselves to cold climates, preferring to stay out of the tropics. And although our business is concerned with Estonia, science is international: everything we do in the research field at the centre of excellence must be publishable in leading scientific journals."

Regarding the existing buildings, the centre of excellence focuses on the renovation of apartment buildings. Nearly 50% of Estonian residents live in apartments that were built between 1950 and 1990 and these uninsulated and unventilated houses by today’s standards are becoming a serious problem in terms of high energy costs, quality of life and national energy saving obligations. So far, the studies have been able to lead to development of the technology for the renovation of apartment buildings, but its broad application and ensuring affordability for all social groups needs some serious work.

Kurnitski stresses that renovation processes must support Estonia's regional development and improve people's livelihoods. "It should not cause more energy poverty and that danger exists. When buildings are renovated, their value immediately increases along with the rental price, thus their affordability decreases," he says as an example. The involvement of social scientists is crucial to analyse whether renovation support goes to the right target groups and what is the attitude of people towards new technical solutions. The topics of artificial intelligence and data-based energy use are important, as new and renovated buildings are technically complex and require data-based and automated monitoring. In this way, it is possible to ensure that technical systems work as designed, which is a prerequisite for providing good indoor climate and low energy costs.

Professor Riina Aav: we want to contribute to a more efficient use of resources

The new Centre of Excellence in Circular Economy for Strategic Mineral and Carbon Resources will also work on improving living conditions. The bigger goal of the Centre of Excellence is to help solve or overcome technological problems related to the (re)use of mineral and carbon-based resources; create new material processing technologies, find solutions for better management of complex supply chains and ensure the quality of recyclable materials, while also evaluating the suitability and sustainability of technologies for the circular economy.

Under the leadership of Professor Riina Aav, around 40 Estonian researchers from different academic backgrounds will be working towards this common goal. They are joined by five advisory board members outside of Estonian universities, including a head of a large company, an adviser on green policies and several renowned professors. "The research results of collaborating scientists can significantly contribute to sustainable development and more efficient use of resources in a global context," says professor Riina Aav.

"We submitted the application by the centre of excellence as a continuation of our activities in the circular economy core laboratory in our university. The latter was created thanks to an initiative group, which included scientists from various fields – earth and chemical scientists, chemical engineers and economic experts – who wanted to contribute to a sustainable Estonian economy," says Aav. As a reflection of what was happening in society, they started discussing and looking for ways the university and researchers could contribute even more. According to Aav, the answer was simple - they could achieve this through their research, for example by developing new technologies.

"We realised that there are many advantages to collaboration between various fields. Focusing our core activities on the circular economy helps us develop our own competence at the university. This, in turn, helps us to teach the students better, because if we do the research in the laboratory and are familiar with the scientific literature, then we are also better at conveying the information to the students," says Aav.

Our partners from the Department of Business Administration informed us that the ministries that develop national plans, as well as local governments and businesses ask for advice from economists, but new technologies are not created based on economics alone – it is necessary to involve engineering and natural scientists. "We started thinking – we need to establish a pan-Estonian centre that would not just include people from Tallinn University of Technology," says the professor.

Aav believes that one of the strengths of their application was that within the project, the interdisciplinary team in the core laboratory was expanded, i.e. various scientific fields were represented even more – now also regionally. "We brought in competent people from the University of Tartu and elsewhere. For example, researchers Rutt Hints and Veiko Karu from the Department of Geology are from us and we were also joined by the state institution the Estonian Geological Survey headed by Sirli Sipp Kull and earth scientists from the University of Tartu. Academician Kalle Kirsimäe from Tartu is very visible in society and at the top of his field," the head of the centre of excellence says.

According to Aav, they kept moving forward step by step. Just as the circular economy envisages using everything as efficiently as possible, the same applies figuratively to scientists. As the science of geology and mineral resources focuses on mineral or inorganic compounds, inviting Andres Trikkel's research group to the centre of excellence was a logical step, as it has been working with technologies related to inorganic substances for years, says Aav. "Next, we thought that if we have a working group for mineral raw materials, then another important class of materials is all kinds of bio, wood and plastic materials, that is, we also needed a working group for carbon-based raw materials. I have a background in organic chemistry and junior professor of flow chemistry Maksim Ošeka and professor Lauri Vares from Tartu joined us as well, the latter, for example, studies the production of bio-based plastics and the valorisation of wood," she continues.

The circle kept expanding. Next, people from the fields of chemical engineering and industrial chemistry joined us – professor Sergei Preis is an expert in water treatment technologies and professor Margus Lopp, the leading researcher at TalTech, is an outstanding name in the field of industrial chemistry, whose laboratory head Kristiina Kaldas will lead the centre's industrial transfer working group together with Sergei Preis.

"Water as a raw material cannot be excluded from the circle," notes Aav. "However, the water is purified using chemical methods. What can we do with the residues or how can we use them? This requires knowledge in organic chemistry and resource upcycling."

However, this field of chemical technology is related to basic sciences, so that the technologies developed in the laboratory can be further developed on a larger scale. For this, in turn, we need to find industrial partners. Therefore, the research groups of TalTech's Virumaa College, led by Allan Niit and Olga Pihl, are a part of the industrial transfer working group. In addition to large-scale industry, the field of small businesses needs to be developed, which is why the enterprising electrochemist Dr. Ivar Kruusenberg and his research group from the UT National Institute of Chemical Physics and Biophysics have also joined the industrial transfer team.

Finally, technologies must also be "brought" to society. "This means that we – chemists, earth scientists and engineers – must be able to find a common language with people who deal with the economy side of the topic. Business administration and circular economic models come into play, with the working group headed by Tarmo Kalvet, who knows how to communicate with society about our technologies – state and municipal institutions, decision-makers and, of course, entrepreneurs."

Thanks to the Centre of Excellence, it was possible to create a complete circle of the most diverse researchers and competencies that have the potential to bring technologies to society. However, it will take some time to get any results, says Aav. "We are a new collaboration group and all these people came up with the idea to do something together. So far, only a few groups have cooperated with each other, that's why I thought it was very important to look for good external advisors as well."

To date, an advisory body has been established, which includes three professors from abroad: Peter Somfai from Lund University in Sweden, Timothy Noël from the University of Amsterdam in the Netherlands and Sachin M. Chavan from the University of Stavanger in Norway. In addition, Silmet's head chemist Raivo Vasnu was invited as an advisor, representing one of Europe's most strategic companies that produces rare, high-purity earth metals that are needed for the production of magnets and all kinds of electric motors. Mihkel Krusberg, adviser to the Ministry of Climate and the European Union's environmental policy maker and an expert in circular economy and plastics, was also invited as an independent member.

"I have a feeling that this team has great potential. And I think that's what ultimately led to the funding. The first results should be apparent at the beginning of 2025, when we will be able to talk about our work in more detail," says Aav.