In the pursuit of energy efficiency and sustainability, two Estonian public buildings were designed to meet the rigorous passive house standard, aiming to drastically reduce energy consumption and greenhouse gas emissions. However, a recent study published in the Proceedings of the Estonian Academy of Sciences, translated as the “Proceedings of the Estonian Academy of Sciences,” reveals that despite their high-quality envelopes, these buildings fell short of their ambitious goals. The research, led by Indrek Raide from the Chair of Building Physics and Energy Efficiency at Tallinn University of Technology, offers valuable insights into the challenges and pitfalls of constructing nearly zero-energy buildings.
The study focuses on two non-residential buildings—one refurbished and one newly constructed—both initially intended to adhere to the passive house standard. Despite their high-performance envelopes, the buildings failed to meet the desired energy efficiency levels. Raide and his team identified several key reasons for this underperformance, including overly simplified control of building service systems, overly optimistic energy calculations, and inadequate initial data. Additionally, the buildings experienced overheating during both winter and summer seasons, and the air leakage rate of the building envelope was higher than expected.
One of the most significant findings was the lack of conscious project leadership and inadequate final component selection. “The main reasons for these shortcomings are lack of conscious project leadership and inadequate final component selection,” Raide emphasized. This highlights the critical role of project management and decision-making in achieving energy efficiency goals.
The implications of this research are substantial for the energy sector and the construction industry. As the European Union strives to reduce energy dependence and greenhouse gas emissions, the lessons learned from these Estonian buildings can guide future projects. Investors, constructors, and designers must pay closer attention to the details of building service systems, energy calculations, and component selection to avoid similar pitfalls.
Raide’s study underscores the importance of realistic assumptions and thorough planning in the design and construction phases. “Good examples and analysis of real performance are needed to motivate investors, constructors, and designers to evoke changes and warn against possible failures,” Raide noted. By learning from these experiences, the industry can move closer to achieving nearly zero-energy buildings that are both efficient and comfortable.
As the world continues to grapple with climate change and energy sustainability, the insights from this research are timely and relevant. The study serves as a cautionary tale and a roadmap for future developments in the field of energy-efficient construction. By addressing the identified shortcomings, the industry can make significant strides toward a more sustainable and energy-efficient future.