## 2 Energy Efficiency and Public Buildings  
It was noticed by the European Commission (EC) more than 10 years ago that about 40% of final energy consumption (and 36% of greenhouse gas emissions) was recorded in buildings. Therefore, buildings have been identified as one of the key areas of action for EE [14]. Since the problem was identified by the EC, several initiatives have been introduced, such as regulations, guidelines, and provisions. It was also noted that it is crucial to put more emphasis on EE in the public sector, including public procurement, renovation of public buildings, and encouraging higher construction standards. The EU has taken action by showing that environmental and energy considerations are being considered in buildings occupied by public authorities and buildings frequented by the public. For that, the Energy Performance of Buildings Directive (2010/31/EU, as amended 2018/844/EU) was introduced and the Commission established a set of standards and accompanying technical reports called Energy Performance of Buildings Standards (EPB standards), which are managed by the European Standardization Committee (CEN/CENELEC). Another initiative--General Block Exemption Regulation (GBER)--identifies support for investments, including electric vehicle charging devices/points in buildings; an integrated on-site power plant producing electricity or heat from renewable sources, including related on-site storage facilities; and investments leading to the digital transformation of buildings to enhance their smart readiness [9]. The Commission indicated that EU member states carry out energy efficient renovations of at least 3% of the total floor area of buildings ownedand occupied by central governments [15]. To support the owners of buildings, several best practices have been published. Among them, the following examples of retrofitting techniques listed by the EU Green Best Practice Platform [16] are changing insulation materials, increasing insulation thickness and improving the environmental performance of roofs, using more efficient glazing sashes and frames, using internal and external shading devices, improving airtightness by improving doors, adding fast-acting doors, sealing air leakages and creating buffer sections, and maintenance. A valuable initiative in which many public building owners were involved was public-private partnerships programs that offered wide support for refurbishment and helped to optimize energy savings performance contracts [17]. The potential of this initiative seems to be untapped by most universities.  
The improvement of energy efficiency is a part of the sustainable development policy. The EE area is intensively explored by scientists. Relationships between management, energy efficiency, and sustainable development have already been the subject of research by Polish and foreign researchers. The debate on energy efficiency is multi-threaded, touching on financial, economic, social, and technical issues, barriers, and effects [18].  
Among the areas that improve the energy efficiency of building use, the literature lists processes and equipment related to heating, cooling, ventilation, and building lighting. The investments analyzed in this area include thermal modernization, insulating walls ceilings and floors, replacing windows, purchasing equipment that generates energy or heat from renewable sources and storage equipment, or installing smart devices and apps to improve the efficiency of energy consumption in the building [19]. The literature also indicates methods for identifying the impact of key building elements on the environment throughout the life cycle of the element [20]. Currently, universities in Poland are struggling with several issues related to planning their major renovations and implementing energy efficient modernizations. Only a few of the buildings have energy performance or audit documentation.