- Faculty of Environmental Engineering
- Faculty Departments
- Department of Building Energetics
Department of Building Energetics
This is a nationally leading specialised academic unit that prepares engineers to develop, evaluate, and manage energy-efficient and sustainable buildings and building engineering systems.
About the Department
Department Activity Areas
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Direct collaboration with industry and strong labour market demand for graduates.
The Department maintains active cooperation with leading companies in Lithuania and internationally.The Department maintains active cooperation with leading companies in Lithuania and abroad operating in heating, ventilation, cooling, heat and gas supply, and renewable energy systems. Its partners include design, manufacturing, and maintenance companies, ministries, agencies, and related institutions. Graduates of the Department are highly valued in the labour market, as evidenced by scholarships awarded by three major companies to the best-performing students. Students gain hands-on experience during their studies and frequently begin their professional careers before graduation.
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Advanced Building and Energy Systems Laboratories
The Department has modern laboratories for student and researcher experiments.The Department operates modern laboratories that enable experimental work with real building microclimate systems. Research and educational studies are carried out using thermography, digital twins, and computer modelling, supporting the development of innovative solutions to enhance the efficiency of energy transformation, supply, and consumption.
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International visibility and participation in European projects
The Department’s academic staff and researchers actively participate in international and national research and innovation projects.Academic staff and researchers of the Department are actively engaged in Horizon Europe, COST, LIFE, and other international and national research and innovation programmes. Students are integrated into research groups, where they gain practical experience, develop expertise, and build professional networks at an international level.
Building Energy and Microclimate Systems Laboratory
This laboratory belongs to the Department of Building Energy Engineering.
The BEMS Laboratory researches, develops, and applies solutions for building energy supply, as well as energy consumption systems and processes. Its research contributes to sustainable energy use and the development of modern buildings.
About the Laboratory
Goals
- Providing research and knowledge dissemination services on building energy performance, energy efficiency, and indoor microclimate quality;
- Researching and implementing renewable energy integration solutions in building energy systems;
- Assessing the life cycle and thermodynamic performance of building energy supply and consumption systems;
- Integrating, modelling, and planning building energy supply and use systems and processes.
Services
The laboratory’s services are listed below.
Modelling of energy converters and systems
TRNSYS 17.0 (building microclimate and energy demand), DesignBuilder (interaction between building envelope elements, systems, microclimate, and energy demand), Polysun (processes in solar energy converters and their systems), EnergyPro (regional/area energy supply, particularly co- and trigeneration), PHPP (supporting design software for the Passive House standard), SimaPro (life cycle assessment), HEAT2/HEAT3 (two- and three-dimensional transient heat transfer), and PHOENICS (computational fluid dynamics).
Technical feasibility assessment of the integration of renewable energy sources in buildings.
The research covers the use of renewable energy sources such as solar, wind, geothermal energy, biofuels, and others to meet building energy needs. The work includes analysis of current building energy demand, which allows energy and capacity balances to be established. A technical assessment of renewable energy integration is carried out, conceptual technical solutions are proposed, and economic and environmental evaluations of the suggested alternatives are performed. The search for financial support for selected implementation options is also undertaken at national and EU levels.
Building energy audit with on-site measurement of actual energy parameters.
A building energy audit includes assessment of the technical condition of the building envelope and engineering systems, analysis of energy consumption, and energy normalisation calculations. On-site measurements are carried out using thermography, thermal resistance testing, and airtightness analysis. A calibrated energy model is created based on measured and historical energy data. Energy-saving measures are proposed, and their economic feasibility is evaluated. Specialists may also participate in ESCO projects and provide concept development and technical and economic assessment of heat sources and integrated solutions.
Energy planning: preparation of district heating development plans and feasibility studies for energy supply in residential areas.
Specialists develop territorial heating plans and conduct feasibility studies on sustainable energy supply for settlements, focusing on renewable energy development and environmental impact reduction. They also prepare documentation required for project funding.
The Centre works with responsible real estate developers planning energy-efficient residential areas. The Department offers consultancy at the design stage, support in joining EU demonstration programmes, and assistance in preparing funding applications.
Building thermographic analysis and measurement of the actual thermal resistance of building envelope elements.
Thermographic analysis of thermal structures using images (photographs) and dynamic processes in video format is carried out. The thermal performance of building envelope elements is assessed, and potential construction defects and specific problem areas are identified. Measurements of the actual thermal resistance of envelope elements are then performed in these areas. Conclusions are provided, and the results serve as a basis for defining defect remediation requirements.
Building or indoor microclimate assessment
In the assessed building, measurements are carried out of air and surface temperatures, relative humidity, CO₂ levels, airtightness, lighting, and noise. Ventilation airflow rates are also measured. The collected data are analysed, and conclusions are provided on possible solutions to identified problems.
Airtightness assessment of buildings or premises
A pressure test is performed in the building or room, with thermal imaging used to identify leakage areas. The air change rate at 50 Pa pressure difference is measured, and the results are used for building certification purposes.
Ventilation system assessment
Measurements of air velocity and duct pressure are performed to support the adjustment and balancing of ventilation systems.
Experimental studies of low-capacity heat transformers
These studies determine the seasonal energy efficiency of low-capacity (up to several tens of kW) energy converters, such as heat exchangers, heat pumps, refrigeration units, and boilers. The operating characteristics of these systems are analysed, and the impact of new components or equipment modifications on performance is assessed. Recommendations are provided to improve efficiency and optimise operating and energy transformation modes.
Contacts
Head of the Laboratory:
Dr. Dovydas Rimdžius
Phone: +370 5 251 2129
Email: dovydas.rimdzius@vilniustech.lt
Partners
Department of Building Energetics maintains active cooperation with social and business partners.
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Department Staff
The Department’s academic staff are recognised professionals with strong expertise in sustainability principles, integrating advanced technologies and teaching methods into their work. They are actively engaged in research and international projects and maintain close cooperation with the alumni community, which is involved in the study process. Lecturers are highly regarded by students for their teaching quality, professional competence, and constructive communication.
Administration
- Administration
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Prof. Dr. Violeta MotuzienėHead
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Dr. Dovydas RimdžiusHead of Laboratory(ies)
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Thesis abstracts
Years
Qualification
Clear selections
Agnė Kanapeckaitė
— Dr Rūta Mikučionienė
Application and Evaluation of an Integrated Model for Smart City Development in the Capital’s Suburban Regions
This master’s thesis examines an integrated approach to smart and socially sustainable municipal development in the suburban regions of the capital city. The thesis analyses the evolution of...
Application and Evaluation of an Integrated Model for Smart City Development in the Capital’s Suburban Regions
Student:
Agnė Kanapeckaitė
Supervisor:
Dr Rūta Mikučionienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamas integruotas požiūris į sumanaus ir socialiai tvaraus savivaldybės vystymąsi sostinės priemiestiniuose regionuose. Darbe analizuojama sumanaus miesto sampratos raida, tvaraus ir sumaniai tvaraus miesto sąsajos, socialinės infrastruktūros, aplinkos tvarumo bei bendruomenės ir valdysenos reikšmė savivaldybių vystymuisi. Teorinėje dalyje pagrindžiama, kad sumanus savivaldybės vystymasis neturėtų būti siejamas vien su technologijų diegimu, nes technologiniai sprendimai turi būti vertinami kartu su socialine infrastruktūra, aplinkosauginiu atsparumu, gyventojų įtraukimu ir valdysenos kokybe.
Tyrime parengta Ukmergės rajono ir Elektrėnų savivaldybių sumanaus ir socialiai tvaraus vystymosi vertinimo sistema, sudaryta iš socialinės infrastruktūros, aplinkos tvarumo bei bendruomenės ir valdysenos kriterijų grupių. Empirinėje darbo dalyje taikoma mokslinės literatūros analizė, statistinių ir technologinių duomenų analizė, ekspertinis vertinimas, SWARA kriterijų svorių nustatymo metodas ir svertinio indekso skaičiavimas.
Darbą sudaro 3 dalys: įvadas, sumanaus ir socialiai tvaraus savivaldybės vystymosi teoriniai pagrindai, tyrimo metodika, Ukmergės rajono ir Elektrėnų savivaldybių vertinimo rezultatai, išvados ir siūlymai, literatūros sąrašas.
Darbo apimtis – 136 psl. teksto be priedų, 20 iliustracijų, 52 lentelės, 94 bibliografiniai šaltiniai.
Atskirai pridedami darbo priedai.
Thesis abstract (EN)
This master’s thesis examines an integrated approach to smart and socially sustainable municipal development in the suburban regions of the capital city. The thesis analyses the evolution of the smart city concept, the links between sustainable and smart sustainable cities, and the importance of social infrastructure, environmental sustainability, community involvement and governance for municipal development. The theoretical part substantiates that smart municipal development should not be associated solely with the implementation of technologies, as technological solutions should be assessed together with social infrastructure, environmental resilience, citizen involvement and the quality of governance.
The study develops an assessment framework for the smart and socially sustainable development of Ukmergė District Municipality and Elektrėnai Municipality, consisting of three groups of criteria: social infrastructure, environmental sustainability, and community and governance. The empirical part of the thesis applies scientific literature analysis, statistical and technological data analysis, expert evaluation, the SWARA method for determining criteria weights, and weighted index calculation.
The thesis consists of three parts: an introduction, the theoretical foundations of smart and socially sustainable municipal development, the research methodology, the assessment results of Ukmergė District Municipality and Elektrėnai Municipality, conclusions and recommendations, and the list of references.
The thesis comprises 136 pages of text excluding appendices, 20 figures, 52 tables and 94 bibliographic sources. Appendices are attached separately.
Aistė Jakutė
— Assoc Prof Dr Olga Lingaitienė
Integration of Sustainability into Industrial Business Models: Adaptation to Climate Change, Promotion of Innovation, and Ensuring Long-Term Profitability
This master’s thesis examines the impact of integrating sustainability indicators into industrial business models on organizations’ adaptation to climate change, the promotion of innovation, and the ensuring of...
Integration of Sustainability into Industrial Business Models: Adaptation to Climate Change, Promotion of Innovation, and Ensuring Long-Term Profitability
Student:
Aistė Jakutė
Supervisor:
Assoc Prof Dr Olga Lingaitienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamas tvarumo rodiklių integravimo į pramonės įmonių verslo modelius poveikis organizacijų prisitaikymui prie klimato kaitos, inovacijų skatinimui bei ilgalaikio verslo pelningumo užtikrinimui. Tyrime analizuojamos „Nestle“, „Mondelez International“ ir „Coca-Cola HBC“ organizacijos.
Darbo metu atliekama viešai skelbiamų tvarumo ataskaitų bei tvarumo ir finansinių rodiklių pokyčių analizė, siekiant įvertinti organizacijų pažangą tvarumo srityje 2018–2024 m. laikotarpiu. Siekiant nustatyti reikšmingiausias aplinkai ir organizacijoms sritis, turinčias didžiausią įtaką verslo veiklai ir ilgalaikei sėkmei, atliekama dvejopo reikšmingumo analizė.
Tyrimo metu taip pat nustatomi ryšiai tarp tvarumo rodiklių ir finansinių rezultatų pokyčių, leidžiantys identifikuoti, kurios tvarumo sritys yra teigiamai arba neigiamai susijusios su organizacijų finansiniais rezultatais. Papildomai vertinami inovacijų skatinimo ir prisitaikymo prie klimato kaitos rodikliai, analizuojamos jų tendencijos bei pasiekti rezultatai viso nagrinėjamo laikotarpio metu.
Išnagrinėjus teorinius ir praktinius tvarumo integracijos į pramonės verslo modelius aspektus, pateikiamos baigiamojo magistro darbo išvados.
Darbą sudaro 6 dalys: įvadas, tvarumo integravimo į pramonės įmonių verslo modelius teoriniai aspektai, tvarumo integracijos į pramonės verslo modelius tyrimo metodologija, pradiniai duomenys ir analizė, išvados ir literatūros sąrašas.
Darbo apimtis – 76 p. teksto be priedų, 26 iliustr., 7 lent., 52 literatūros šaltiniai.
Atskirai pridedami darbo priedai.
Thesis abstract (EN)
This master’s thesis examines the impact of integrating sustainability indicators into industrial business models on organizations’ adaptation to climate change, the promotion of innovation, and the ensuring of long-term business profitability. The study analyzes „Nestle“, „Mondelez International“, and „Coca-Cola HBC“.
The research includes an analysis of publicly available sustainability reports as well as changes in sustainability and financial indicators in order to evaluate the organizations’ progress in the field of sustainability during the 2018–2024 period. To identify the areas that are most significant both to the environment and to the organizations, and that are critical to long-term business success, a double materiality analysis is conducted.
The study also identifies relationships between changes in sustainability indicators and financial performance, enabling the determination of which sustainability areas are positively or negatively associated with organizations’ financial results. In addition, indicators related to innovation promotion and adaptation to climate change are evaluated, together with their trends and achieved results throughout the analyzed period.
After examining the theoretical and practical aspects of sustainability integration into industrial business models, the conclusions of the master’s thesis are presented.
The thesis consists of six parts: introduction, theoretical aspects of sustainability integration into industrial business models, research methodology of sustainability integration into industrial business models, initial data and analysis, conclusions, and references.
The thesis comprises 76 pages of text excluding appendices, 26 figures, 7 tables, and 52 references.
The appendices are provided separately.
Ana Kumponienė
— Dr Giedrė Lapinskienė
Green Transformation Model for the Construction Sector
The master’s thesis examines the issues related to the evaluation of green transformation in the construction sector, its necessity, and its main principles. The study analyzes environmental and...
Green Transformation Model for the Construction Sector
Student:
Ana Kumponienė
Supervisor:
Dr Giedrė Lapinskienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamos statybos sektoriaus žaliosios transformacijos vertinimo problemos, jos būtinybė ir pagrindiniai principai. Analizuojami aplinkosauginiai ir valdysenos veiksniai, darantys įtaką žalumo sprendinių formavimui, bei aptariama statybos įmonių praktika šioje srityje.
Darbo metu išnagrinėti daugiakriterinio vertinimo principai ir suformuota žaliosios transformacijos vertinimo kriterijų sistema, apimanti aplinkosauginius ir valdysenos rodiklius. Projektų vertinimui taikomas TOPSIS metodas, leidžiantis nustatyti jų artumą idealiai žaliosios transformacijos būsenai.
Remiantis empirinės analizės rezultatais, identifikuotos pagrindinės žaliosios transformacijos kryptys, atspindinčios efektyviausius statybos projektų sprendinius. Tyrimo pagrindu sukurtas statybos sektoriaus žaliosios transformacijos modelis, leidžiantis kompleksiškai vertinti projektus ir pagrįsti sprendimų priėmimą, integruojant teorines įžvalgas ir empirinius duomenis.
Darbo rezultatai parodė, kad aukščiausius vertinimus lemia išteklių naudojimo efektyvumas, aplinkos poveikio mažinimas ir duomenimis grįstas sprendimų priėmimas. Taip pat nustatyta, kad efektyviausi sprendiniai grindžiami kelių kriterijų derinimu ir kompleksiniu požiūriu į žaliosios transformacijos įgyvendinimą.
Išnagrinėjus teorinius ir praktinius aspektus, darbe pateikiamos išvados ir rekomendacijos, skirtos žalumo didinimui statybos sektoriuje bei žalių pastatų projektavimui.
Darbą sudaro trys pagrindinės dalys: įvadas, mokslinė literatūros analizė, žaliosios transformacijos modelio vertinimo metodologija ir empirinis tyrimas, taip pat išvados ir siūlymai, literatūros sąrašas ir priedai.
Darbo apimtis – 83p. teksto be priedų, 18 iliustracijų, 20 lentelių, bibliografiniai šaltiniai.
Atskirai pridedami darbo priedai.
Thesis abstract (EN)
The master’s thesis examines the issues related to the evaluation of green transformation in the construction sector, its necessity, and its main principles. The study analyzes environmental and governance factors influencing the development of green solutions and reviews the practices of construction companies in this area.
The research explores the principles of multi-criteria evaluation and develops a system of criteria for assessing green transformation, encompassing environmental and governance indicators. The TOPSIS method is applied to evaluate projects, enabling the assessment of their proximity to the ideal state of green transformation.
Based on the empirical analysis, the main directions of green transformation are identified, reflecting the most effective solutions in construction projects. A model of green transformation for the construction sector is developed, which enables a comprehensive assessment of projects and supports decision-making by integrating theoretical insights with empirical data.
The results indicate that the highest evaluations are primarily determined by resource use efficiency, reduction of environmental impact, and data-driven decision-making. It is also established that the most effective solutions are based on the combination of multiple criteria and a systemic approach to implementing green transformation.
Based on the theoretical and practical analysis, conclusions and recommendations are provided for enhancing green practices in the construction sector and for the development of green buildings.
The thesis consists of three main parts: an introduction, a review of scientific literature, the methodology for evaluating the green transformation model, and an empirical study, followed by conclusions and recommendations, a list of references, and appendices.
The scope of the thesis is 83 pages of text (excluding appendices), 18 figures, 20 tables, and references.
The appendices are presented separately.
Augustė Salanovičiūtė
— Dr Rasa Džiugaitė-Tumėnienė
Design of Indoor Climate Systems for a Shopping Centre in Klaipeda
This bachelor’s thesis presents calculations of design-specific heat losses and energy requirements for space heating, ventilation, and cooling for a shopping center in Klaipėda. The thesis includes designs...
Design of Indoor Climate Systems for a Shopping Centre in Klaipeda
Student:
Augustė Salanovičiūtė
Supervisor:
Dr Rasa Džiugaitė-Tumėnienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame bakalauro darbe atlikti prekybos centro Klaipėdoje projektinių savitųjų šilumos nuostolių, energijos poreikio patalpų šildymui, vėdinimui ir vėsinimui skaičiavimai.
Darbe suprojektuotos šildymo, vėdinimo ir oro vėsinimo sistemos. Baziniame variante projektuojama kombinuota grindinio ir radiatorinio šildymo kolektorinė sistema. Pastato patalpų vėdinimui numatytos dvi pastovaus srauto vėdinimo sistemos su rotaciniais šilumogrąžiais ir viena su priešpriešinių srautų šilumokaičiu. Pastato patalpų oro vėsinimui projektuojama vandeninė vėsinimo sistema su ventiliatoriniais konvektoriais. Sistema užpildyta vandens ir 35 % etilenglikolio mišiniu.
Alternatyviame variante projektuojama kintamo oro srauto vėdinimo sistema, reguliuojama pagal CO2 koncentraciją patalpose.
Darbe atliktas bazinės pastovaus oro srauto vėdinimo sistemos ir dviejų alternatyvių vėdinimo sistemų su kintamo oro srauto sklendėmis ekonominis vertinimas. Alternatyvūs variantai tarpusavyje skiriasi kintamo oro srauto vožtuvų išdėstymu ortakyne. Apskaičiuota šių sistemų grynoji dabartinė vertė 15 metų laikotarpiui. Rezultate ekonominis vertinimas parodė, kad bazinio varianto GDV yra 19 % mažesnė už pirmąją alternatyvą ir 4 % didesnė už antrąją alternatyvą.
Darbą sudaro 16 dalių: įvadas, baigiamojo darbo duomenys, patalpų mikroklimatas ir jo palaikymo sistemos, pastato projektinės šildymo ir vėsinimo galios, pastato vėdinimo sistemos projektavimas, pastato vėsinimo sistemos projektavimas, vėsos punkto projektavimas, pastato šildymo sistemos projektavimas, šilumos punkto projektavimas, valdymo sprendinys, alternatyvių variantų sprendiniai, pastato energijos poreikiai, ekonominis vertinimas, išvados, literatūra, priedai.
Darbo apimtis – 139 puslapiai teksto be priedų, 73 iliustracijos, 55 lentelės, 35 bibliografiniai šaltiniai.
Atskirai pridedami darbo priedai: 19 brėžinių.
Thesis abstract (EN)
This bachelor’s thesis presents calculations of design-specific heat losses and energy requirements for space heating, ventilation, and cooling for a shopping center in Klaipėda.
The thesis includes designs for heating, ventilation, and air cooling systems. The base design includes a combined underfloor and radiator heating manifold system. Two constant air volume ventilation systems with rotary heat exchangers and one with a counterflow heat exchanger are designated for the ventilation of the building’s spaces. A water-based cooling system with fan coil units is designed for cooling the building’s spaces. This system is filled with a mixture of water and 35% ethylene glycol.
An alternative variant is included, presenting the design of a variable air volume (VAV) ventilation system that is controlled based on the concentration CO2 in the rooms.
This thesis includes an economic assessment of the base constant air volume ventilation system and two alternative ventilation systems with variable air volume dampers. The alternative options differ from one another in the arrangement of the variable airflow dampers in the ductwork. The net present value of these systems over a 15-year period was calculated. The economic assessment showed that the NPV of the baseline variant is 19% lower than the first alternative and 4% higher than the second alternative.
This thesis consists of 16 sections: introduction, thesis data, indoor microclimate and its maintenance systems, design heating and cooling capacities of the building, design of the building’s ventilation system, design of the building’s cooling system, design of the cooling station, design of the building’s heating system, design of the heat distribution point, control solution, alternative solutions, building energy requirements, economic assessment, conclusions, references, and appendices.
This thesis consists of 139 pages of text excluding appendices, 73 illustrations, 55 tables, 35 bibliographic sources.
Appendices are provided separately: 19 drawings.
Aušrinė Juozelskė
— Assoc Prof Dr Algita Miečinskienė
Assessment of Sustainability in Pricing for Large Household Appliances
The topic of the master’s thesis is “Assessment of sustainability in pricing for large household appliances”. The aim of the thesis is to assess the importance of product...
Assessment of Sustainability in Pricing for Large Household Appliances
Student:
Aušrinė Juozelskė
Supervisor:
Assoc Prof Dr Algita Miečinskienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamas tvarumo aspektų vertinimas stambiosios buitinės technikos kainodaroje. Darbo tikslas – įvertinti produkto tvarumo rodiklių ir kainos svarbą vartotojų pasirinkimams stambiosios buitinės technikos kategorijoje. Pirmame darbo skyriuje analizuojamos tvarumo, kainodaros, vartotojų suvokiamos vertės bei vartotojų elgsenos sampratos ir kitų autorių atlikti tyrimai. Antrame skyriuje sudaryta tvarumo vertinimo stambiosios buitinės technikos kainodaroje metodika, grindžiama pasirinkimais pagrįstos jungtinės analizės (Choice-Based Conjoint, CBC) metodu. Jame apibrėžtas teorinis ir metodologinis tyrimo pagrindas, CBC metodo taikymo logika bei empirinio tyrimo struktūra. Trečiame darbo skyriuje sudarytas neadaptyvus pilno profilio CBC tyrimo dizainas, kuriame respondentai rinkosi tarp skalbyklių, džiovyklių bei indaplovių alternatyvų, sudarytų iš skirtingų požymių lygių derinių. Tyrime analizuoti šie požymiai: kaina, energijos efektyvumo klasė, garantijos trukmė, prekės ženklas, triukšmo klasė, talpa ir vandens sąnaudos. Duomenys rinkti internetinės apklausos būdu 2026 m. vasario–kovo mėn., naudojant „Google Forms“ platformą. Analizei panaudotas 171 tinkamas respondentų atsakymas. Pasirinkimų duomenys analizuoti „RStudio“ programine įranga, taikant daugiarūšį logitinį (MNL) modelį, apskaičiuojant dalines naudas ir požymių santykinę svarbą. Tyrimo rezultatai parodė, kad vartotojų pasirinkimams didžiausią įtaką darė energijos efektyvumo klasė, garantijos trukmė ir kai kuriose produktų kategorijose prekės ženklas, o kaina ne visais atvejais buvo statistiškai reikšmingas pasirinkimą lemiantis veiksnys. Darbo pabaigoje suformuluotos išvados ir pateiktos rekomendacijos tvarumo kainodarai formuoti stambiosios buitinės technikos kategorijoje.
Darbą sudaro įvadas, trys skyriai, išvados ir rekomendacijos bei literatūros sąrašas.
Darbo apimtis – 96 psl. teksto be priedų, 19 paveikslų, 24 lentelės, 60 bibliografinių šaltinių ir 2 darbo priedai.
Thesis abstract (EN)
The topic of the master’s thesis is “Assessment of sustainability in pricing for large household appliances”. The aim of the thesis is to assess the importance of product sustainability attributes and price in consumer choices for large household appliances category. The first part of the thesis analyses the concepts of sustainability, pricing, perceived consumer value, consumer behavior and previously conducted research. The second part presents a methodology for assessment of sustainability in pricing for large household appliances based on the Choice-Based Conjoint (CBC) method. It defines the theoretical and methodological background of the research, the logic of CBC method application, and the structure of the empirical research. In the third part, a non-adaptive full-profile CBC research design was developed, in which respondents chose between washing machine, dryer and dishwasher alternatives composed of different combinations of attribute levels. The following attributes were analyzed in the study: price, energy efficiency class, warranty period, brand, noise class, capacity, and water consumption. Data were collected through an online survey conducted in February–March 2026 using the Google Forms platform. A total of 171 valid respondent answers were used for analysis. Choice data were analyzed using RStudio software and a multinomial logit (MNL) model by estimating part-worth utilities and the relative importance of attributes. The results of the study showed that energy efficiency class, warranty period, and in some product categories brand were the most important factors influencing consumer choices, while price was not a statistically significant factor in all cases. The thesis concludes with recommendations for the development of sustainability pricing in the category of large household appliances.
The thesis consists of an introduction, three parts, conclusions and recommendations, and a list of references.
The thesis comprises 96 pages of text excluding appendices, 19 figures, 24 tables, 60 bibliographic sources, and 2 appendices.
Benas Rakauskas
— Prof Dr Violeta Motuzienė
Investigation of Building Indoor Climate System‘s Control Options in Balancing Energy Efficiency and Thermal Comfort
This master’s thesis investigates the relationship between building energy efficiency and thermal comfort using dynamic energy simulation methods. The aim of the study is to evaluate the impact...
Investigation of Building Indoor Climate System‘s Control Options in Balancing Energy Efficiency and Thermal Comfort
Student:
Benas Rakauskas
Supervisor:
Prof Dr Violeta Motuzienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame darbe nagrinėjama prekybos paskirties pastato energinio efektyvumo ir šiluminio komforto sąsaja taikant dinaminį energinį modeliavimą. Tyrimo tikslas – įvertinti skirtingų šildymo, vėdinimo ir oro kondicionavimo (ŠVOK) sistemų valdymo scenarijų įtaką pastato energijos poreikiams, CO₂ emisijoms, eksploatacinėms išlaidoms bei vidaus mikroklimato kokybei. Tyrimas atliktas, naudojant „Integrated Environmental Solutions Virtual Environment“ (IES VE) programinę įrangą, kurioje sukurtas detalus A++ energinio naudingumo klasės prekybos paskirties pastato modelis. Modelyje įvertintos pastato atitvarų charakteristikos, vidaus šilumos pritėkiai, užimtumo grafikai bei ŠVOK sistemų veikimo režimai.
Darbo metu sudaryti ir išanalizuoti aštuoni skirtingi ŠVOK sistemų valdymo scenarijai, apimantys ankstesnį sistemų paleidimą, optimalaus starto funkcijos taikymą bei įvairias temperatūrų keitimo strategijas ne darbo metu. Gauti rezultatai vertinti pagal pirminės energijos sąnaudas, šildymo ir vėsinimo energijos poreikius, CO₂ emisijas, metines eksploatacines išlaidas bei šiluminio komforto rodiklius, naudojant PMV metodą pagal ISO 7730 standartą. Scenarijų palyginimui taikytas daugiakriteris SAW metodas.
Tyrimo rezultatai parodė, kad didžiausią įtaką energiniam efektyvumui turi temperatūrų valdymas ne darbo metu. Nustatyta, kad taikant 2°C šildymo temperatūros sumažinimą ir papildomą 1 °C vėsinimo temperatūros paaukštinimągalima sumažinti pirminės energijos poreikį elektrai iki 5,14 %, šildymo energijos poreikį iki 10,41 %, vėsinimo energijos poreikį iki 17,21 %, o CO₂ emisijas – iki 6,58 %, lyginant su baziniu scenarijumi. Atliktas daugiakriteris vertinimas parodė, kad racionalus ŠVOK sistemų valdymas leidžia sumažinti energijos sąnaudas ir eksploatacinius kaštus, išlaikant pakankamai aukštą šiluminio komforto lygį.
Thesis abstract (EN)
This master’s thesis investigates the relationship between building energy efficiency and thermal comfort using dynamic energy simulation methods. The aim of the study is to evaluate the impact of different heating, ventilation and air conditioning (HVAC) control strategies on building energy demand, CO₂ emissions, operational costs and indoor environmental quality. The research was carried out using the “Integrated Environmental Solutions Virtual Environment” (IES VE) software, where a detailed dynamic model of an A++ energy class commercial building was developed. The model included building envelope characteristics, internal heat gains, occupancy schedules and HVAC operational parameters.
Eight different HVAC control scenarios were developed and analyzed, including earlier system start–up schedules, application of the “Optimal Start” function and various temperature setback strategies during unoccupied periods. The obtained results were evaluated according to primary energy consumption, heating and cooling demand, CO₂ emissions, annual operational costs and thermal comfort indicators using the PMV method based on ISO 7730 standard. A multi–criteria SAW method was applied for scenario comparison and overall assessment.
The results demonstrated that temperature control during unoccupied periods has the greatest impact on building energy performance. The study determined that applying a 2 °C heating setback combined with an additional 1 °C cooling setback can reduce primary electricity demand by up to 5.14 %, heating energy demand by 10.41 %, cooling energy demand by 17.21 %, and CO₂ emissions by 6.58 % compared to the baseline scenario. The multi–criteria analysis confirmed that rational HVAC control strategies can significantly reduce energy consumption and operational costs while maintaining an acceptable level of thermal comfort.
Deividas Urbonas
— Assoc Prof Dr Kęstutis Valančius
Indoor Climate Systems in a Three-Story Hotel Building
In this work, microclimate systems are designed for a three-story hotel building in V. Žalakevicius Street, Antakalnis microdistrict, Vilnius. The building is connected to the city's heat and...
Indoor Climate Systems in a Three-Story Hotel Building
Student:
Deividas Urbonas
Supervisor:
Assoc Prof Dr Kęstutis Valančius
Department:
Department of Building Energetics
Thesis abstract (LT)
Šiame darbe suprojektuotos mikroklimato sistemos trijų aukštų viešbučio pastatui V. Žalakevičiaus g., Antakalnio mikrorajone, Vilniuje. Pastatas yra prijungtas prie miesto šilumos ir elektros tinklų. Gyvenamųjų patalpų plotas – 625 m², bendras – 770 m². Projektuojama energinio naudingumo klasė yra A++. Pastato vėdinimo sistemą sudaro 2 atskiros OTI sistemos. Viena sistema aprūpina gyvenamąsias patalpas, kita – bendro naudojimo. Abu oro ruoštuvai įrengti ant stogo. Visame pastate suprojektuota radiatorinė šildymo sistema. Šilumnešis yra vanduo, o šilumos šaltinis – centralizuoti šilumos tinklai. Apskaičiuota ir parinkta reikiama šildymo sistemos įranga ir suprojektuotas šilumos punktas. Gyvenamosios paskirties patalpose suprojektuota vandeninė vėsinimo sistema, kuriose numatomi ventiliatoriniai konvektoriai ir į kuriuos tiekiamas vandens ir 35 % etilenglikolio mišinys. Vėsinimo agregatas numatomas ant stogo. Apskaičiuota ir parinkta reikiama vėsinimo sistemos įranga. Nagrinėjama alternatyva – šilumos siurblys oras-vanduo su saulės elektrine. Šiai alternatyvai atliktas ekonominis vertinimas 20 metų eksploataciniam laikotarpiui. Darbo apimtis – 100 psl. be priedų, 51 lentelė, 49 iliustracijos, 17 šaltinių, 25 priedai.
Thesis abstract (EN)
In this work, microclimate systems are designed for a three-story hotel building in V. Žalakevicius Street, Antakalnis microdistrict, Vilnius. The building is connected to the city's heat and electricity networks. The area of residential premises is 625 m², total - 770 m². The designed energy efficiency class is A++. The ventilation system of the building consists of 2 separate AHU systems. One system supplies residential premises, the other for common use. Both air handlers are installed on the roof. A radiator heating system is designed throughout the building. The heat carrier is water, and the heat source is centralized heat networks. The necessary equipment for the heating system was calculated and selected, and the heat substation was designed. In residential premises, a water cooling system is designed, where fan convectors are provided and to which a mixture of water and 35% ethylene glycol is supplied. The cooling unit is planned on the roof. The necessary cooling system equipment is calculated and selected. The alternative under consideration is an air-to-water heat pump with a solar power plant. For this alternative, an economic evaluation was performed for a 20-year operating period. Volume of the work - 100 pages. without appendices, 51 tables, 49 illustrations, 17 sources, 25 appendices.
Domantas Arbačiauskas
— Assoc Prof Dr Kęstutis Valančius
Indoor Climate Systems for a Two-Storey Building with Exhibition Spaces and Administrative Premises
The project designs the microclimate systems for a building with exhibition spaces and administrative premises, and includes dynamic building simulations to determine heating and cooling capacities as well...
Indoor Climate Systems for a Two-Storey Building with Exhibition Spaces and Administrative Premises
Student:
Domantas Arbačiauskas
Supervisor:
Assoc Prof Dr Kęstutis Valančius
Department:
Department of Building Energetics
Thesis abstract (LT)
Šiame darbe suprojektuotos pastato su ekspozicijų erdvėmis ir administracinėmis patalpomis mikroklimato sistemos bei atliktas pastato dinaminis modeliavimas, šildymo ir vėsinimo galioms ir metiniams energijos poreikiams nustatyti. Projektuojamo pastato energinio naudingumo klasė - A++, bendras pastato plotas - 1093,7 m2. Pastate projektuojamos 2 vėdinimo sistemos. OTIS-1 skirta rūsio patalpoms ir pirmame aukšte esančiam holui bei sandėliui. OTIS-2 numatoma ekspozicijų erdvėms, WC patalpoms ir visam antram aukštui. Pirmame ir antrame aukštuose suprojektuotas žemų temperatūrų grindinis šildymas. Šildymo sistemos šilumnešis - vanduo. Šiluma tiekiama centralizuotais šilumos tinklais. Parinkta visa reikalinga šildymo sistemos ir šilumos punkto įranga bei armatūra. Pastatui vėsinti suprojektuota sistema su ventiliatoriniais konvektoriais, kurie įrengiami tose patalpose, kur numatomas nuolatinis žmonių buvimas. Vėsinimo agregatas suprojektuotas ant pastato stogo. Sistemos šaltnešis - vandens ir 35% etilenglikolio mišinys. Šiai sistemai taip pat parinkta visa reikalinga įranga bei armatūra.
Darbe taip pat buvo nagrinėtos alternatyvos - geoterminis šilumos siurblys ir saulės elektrinė. Šioms alternatyvoms buvo atliktas 25 metų ekonominis vertinimas, atsižvelgiant į eksploatacijos ir įrengimo kaštus, bei apskaičiuotas galimas šių sistemų atsiperkamumas.
Darbo apimtis: 96 puslapiai be priedų, 50 lentelių, 53 paveikslai, 25 priedai ir 20 brėžinių.
Thesis abstract (EN)
The project designs the microclimate systems for a building with exhibition spaces and administrative premises, and includes dynamic building simulations to determine heating and cooling capacities as well as annual energy demands. The designed building has an A++ energy performance class and a total area of 1093,7 m². Two ventilation systems are planned. OTIS‑1 serves the basement rooms and the ground‑floor lobby and storage area. OTIS‑2 is intended for the exhibition spaces, sanitary facilities, and the entire second floor. Low‑temperature underfloor heating is designed for both the first and second floors. The heating system uses water as the heat transfer medium, with heat supplied from the district heating network. All necessary heating system and heat substation equipment and fittings have been selected. For cooling, a system with fan coil units is designed, installed in rooms intended for continuous human occupancy. The cooling unit is placed on the building roof. The system uses a mixture of water and 35% ethylene glycol as the refrigerant. All required equipment and fittings for this system have also been selected. The work also examines alternative solutions — a geothermal heat pump and a photovoltaic power plant. A 25‑year economic assessment was performed for these alternatives, considering installation and operating costs, and the potential payback of these systems was calculated.
The thesis consists of 96 pages excluding appendices, 50 tables, 53 figures, 25 appendices, and 20 drawings.
Domantas Petrauskis
— Dr Rasa Džiugaitė-Tumėnienė
Evaluation of the Application of Digital Twin of the Vilnius TECH Sustainability Center for the Indoor Climate Monitoring and Analysis
The master’s thesis analyses the application of the digital twin concept for indoor climate monitoring, energy performance assessment and operational optimisation of the VILNIUS TECH Sustainability Centre. The...
Evaluation of the Application of Digital Twin of the Vilnius TECH Sustainability Center for the Indoor Climate Monitoring and Analysis
Student:
Domantas Petrauskis
Supervisor:
Dr Rasa Džiugaitė-Tumėnienė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamas VILNIUS TECH Tvarumo centro skaitmeninio dvynio taikymas pastato mikroklimato stebėsenai, energinio veikimo analizei ir eksploatacijos optimizavimui. Darbe apžvelgiama pastatų energinio efektyvumo, BIM metodologijos, dinaminio energinio modeliavimo ir skaitmeninio dvynio taikymo pastatų eksploatacijos etape problematika. Tyrimo metu surinkti ir paruošti duomenys apie Tvarumo centro pastato geometriją, atitvarų šilumines savybes, ŠVOK sistemas, patalpų naudojimo režimus, faktinius mikroklimato rodiklius ir energijos sąnaudas.
IDA ICE programoje sukurtas dinaminis energinis modelis, kuris naudotas šildymo, vėsinimo ir vėdinimo įrenginių elektros energijos poreikiams įvertinti. Faktinių mikroklimato jutiklių duomenų analizė parodė, kad tiriamose patalpose fiksuojami temperatūros, santykinės drėgmės ir CO₂ koncentracijos svyravimai, o kai kuriose zonose pasireiškia perkaitimo arba nepakankamos oro kaitos rizika. Modeliuotų ir faktinių šilumos sąnaudų palyginimas parodė 32,33 % skirtumą, todėl modelis laikytinas toliau tikslintinu dinaminiu energiniu modeliu.
Darbe atlikta energinio efektyvumo ir oro kokybės gerinimo scenarijų analizė. Nustatyta, kad didžiausią energijos poreikio mažinimo potencialą turi temperatūrų, užimtumo grafikų ir poreikiu valdomo vėdinimo derinys, leidžiantis sumažinti bendrą energijos poreikį 34,3 %. Papildomo vėdinimo scenarijus pagerina oro kokybę auditorijose, tačiau padidina bendrą energijos poreikį. Pateiktos rekomendacijos Tvarumo centro eksploatacijai optimizuoti, plėtojant jutiklių tinklą, tikslinant energinį modelį ir integruojant duomenis į skaitmeninio dvynio aplinką.
Thesis abstract (EN)
The master’s thesis analyses the application of the digital twin concept for indoor climate monitoring, energy performance assessment and operational optimisation of the VILNIUS TECH Sustainability Centre. The thesis reviews issues related to building energy efficiency, BIM methodology, dynamic energy modelling and the use of digital twins during the building operation stage. During the research, data on building geometry, thermal properties of envelope elements, HVAC systems, room usage schedules, measured indoor climate parameters and actual energy consumption were collected and prepared.
A dynamic energy model was developed in IDA ICE and used to evaluate heating, cooling and air handling unit electricity demand. The analysis of measured indoor climate sensor data showed that temperature, relative humidity and CO₂ concentration varied between the analysed zones, while some rooms had a risk of overheating or insufficient air exchange. The comparison between simulated and actual heating energy consumption showed a difference of 32.33 %, indicating that the model should be considered a dynamic energy model requiring further calibration.
The thesis also evaluates several energy efficiency and indoor air quality improvement scenarios. The results show that the greatest energy saving potential is achieved by combining temperature and occupancy schedule optimisation with demand-controlled ventilation, reducing the total energy demand by 34.3 %. The additional ventilation scenario improves air quality in auditoriums but increases the overall energy demand. Recommendations are provided for optimising the operation of the Sustainability Centre by expanding the sensor network, improving the energy model and integrating operational data into the digital twin environment.
Donatas Tijūnaitis
— Prof Dr Indrė Lapinskaitė
Possibilities of Applying a Congestion Charge in Vilnius City: Modeling of the Impact on Traffic Flows and Congestion Duration in the Context of Sustainable Mobility
In the master’s thesis, the possibilities of applying a congestion charge in the city of Vilnius are examined by assessing its potential impact on traffic flows and congestion...
Possibilities of Applying a Congestion Charge in Vilnius City: Modeling of the Impact on Traffic Flows and Congestion Duration in the Context of Sustainable Mobility
Student:
Donatas Tijūnaitis
Supervisor:
Prof Dr Indrė Lapinskaitė
Department:
Department of Building Energetics
Thesis abstract (LT)
Baigiamajame magistro darbe nagrinėjamos spūsčių mokesčio taikymo galimybės Vilniaus mieste, vertinant galimą poveikį eismo srautams ir spūsčių trukmei darnaus judumo kontekste. Tyrimo tikslas – įvertinti skirtingų spūsčių mokesčio taikymo scenarijų poveikį Vilniaus miesto eismo srautams ir spūsčių trukmei. Darbe analizuojama spūsčių problema, spūsčių mokesčio teorinis pagrindimas, tarptautinė taikymo patirtis ir šios priemonės sąsajos su miesto transporto sistemos efektyvumu.
Empirinėje dalyje taikomas ex-ante scenarijų modeliavimas. Sudaromas bazinis scenarijus S0 ir trys alternatyvūs scenarijai S1–S3, kurie skiriasi teritorine aprėptimi, taikymo laiku ir tarifo dydžiu. Skaičiavimai atliekami remiantis JUDU eismo srautų ir spūsčių duomenimis, Aplinkos apsaugos agentūros oro kokybės duomenimis, Vilniaus miesto strateginiais dokumentais ir mokslinėje literatūroje pagrįstomis prielaidomis. Darbe taip pat įvertinamas fiskalinis poveikis, sistemos kaštai, aplinkosauginis kontekstas ir rezultatų jautrumas pagrindinėms prielaidoms.
Tyrimo rezultatai rodo, kad visi analizuoti scenarijai galėtų mažinti spūsčių trukmę ir vėlavimą, tačiau poveikio mastas priklauso nuo teritorinės aprėpties ir tarifo dydžio. Praktinio įgyvendinimo požiūriu pagrįsčiausia alternatyva laikytinas centrinės miesto dalies piko laikotarpio apmokestinimo scenarijus.
Darbą sudaro 6 dalys: įvadas, spūsčių mokesčio teorinė analizė, spūsčių mokesčio taikymo Vilniuje scenarijų sudarymo ir vertinimo metodika, spūsčių mokesčio taikymo Vilniuje scenarijų vertinimas, išvados ir rekomendacijos, literatūros sąrašas.
Darbo apimtis – 94 p. teksto be priedų, 1 iliustr., 27 lent., 99 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.
Thesis abstract (EN)
In the master’s thesis, the possibilities of applying a congestion charge in the city of Vilnius are examined by assessing its potential impact on traffic flows and congestion duration in the context of sustainable mobility. The aim of the research is to assess the impact of different congestion charge implementation scenarios on traffic flows and congestion duration in Vilnius. The thesis analyses the problem of congestion, the theoretical justification of congestion charging, international implementation experience, and the links between this measure and the efficiency of the urban transport system.
The empirical part applies ex-ante scenario modelling. A baseline scenario S0 and three alternative scenarios S1–S3 are developed, differing in territorial coverage, time of application, and tariff level. The calculations are based on JUDU traffic flow and congestion data, air quality data from the Environmental Protection Agency, strategic documents of the Vilnius City Municipality, and assumptions grounded in the scientific literature. The thesis also assesses the fiscal impact, system costs, environmental context, and the sensitivity of the results to the main assumptions.
The research results show that all analysed scenarios could reduce congestion duration and delays; however, the scale of the impact depends on territorial coverage and tariff level. From the perspective of practical implementation, the most justified alternative is considered to be the scenario of charging the central part of the city during peak periods.
The thesis consists of six parts: introduction, theoretical analysis of congestion charging, methodology for developing and assessing congestion charging scenarios in Vilnius, assessment of congestion charging scenarios in Vilnius, conclusions and recommendations, and the list of references.
The scope of the thesis is 94 pages of text, excluding appendices, 1 figure, 27 tables, and 99 bibliographic sources. The appendices to the thesis are submitted separately.