Energy and Environmental Retrofit of Existing School Buildings: Potentials and Limits in the Large-Scale Planning

This chapter summarizes the results of research activities promoted by a 1 group of researchers working in ABC Department—Politecnico di Milano aimed at 2 energy and environmental requalification of school buildings located in the Lombardy 3 region (Italy). The buildings subject to energy audits have been selected considering 4 various factors, including the type of user (e.g. kindergartens, elementary schools, 5 middle schools, etc.), construction period, construction technology and degrada6 tion. The methodological approach considers energy retrofit scenarios with different 7 energy performance targets and required investments. The results of the research, 8 which is concerned with a substantial and diversified existing building stock, provide 9 public administrators decision-making tools and indicators supporting the energy 10 and environmental retrofit actions for the existing schools. Although the potential 11 for energy savings and reduced environmental impact is important in all scenarios, 12 the achievement of very high energy performance targets is not always economically 13 convenient and is sometimes technically impossible to reach. Large-scale energy 14 planning, therefore, always requires in-depth energy audits that allow defining the 15 optimal energy performance targets. The research activities demonstrate that it is 16 convenient, when the energy performance of a building is improved, to consider also 17 the environmental aspects. For some sample school buildings simulation analyses 18 were carried out in accordance with the LEED® protocol, and the higher cost due to 19 environmental enhancement (e.g. the choice of ecological materials, the recycling of 20 demolition materials or the use of renewable energy sources) is absolutely acceptable 21 in the intervention economy. 22

The third research proposes and discusses a study which provides a consider-52 able improvement in the environmental quality of 14 school buildings (pre-schools, 53 primary and secondary) located in two municipalities in Milan Province, northern 54 Italy. On the other hand, to improve the energy performance of public buildings, and in particular school buildings, large investments are required by the Public Adminis-66 tration (PA). The economy over the next several years and the Stability Pact, which 67 is now mandatory for the PA of Italy to reduce the public debt, will most likely limit 68 direct investments.

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As regard the performance quality, the energy retrofit of school buildings aims 70 at high energy performance comparable to that of new buildings. The improvement 71 in energy performance, however, has a specific cost, which increases exponentially 72 the closer we get to the high energy classes. In order to make investments on energy      This study demonstrates that reaching high levels of energy performance to com-128 ply with the EPBD recast could be very difficult or not cost-effective in many cases.

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Sometimes the cost of energy rehabilitation for the increasing of heating performance 130 is comparable with the cost of a new building.  The differences that energize in individual cases, shown in Fig. 3, are due to 154 several factors:  In some cases not all the three scenarios were simulated because interventions 169 were not needed or not applicable for architectural constrains.    To obtain LEED ® certification, the applicant projects must satisfy all the prerequi-206 sites and should be qualified for a number of points to attain the minimum established 207 project ratings equal to 40 points (red line in Fig. 4).

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Having satisfied the basic prerequisites of the program, the applicant projects 209 are then rated according to their degree of compliance within the rating system: 210 eight buildings fall within the level of Certified with an average score equal to 46.1, 211 while the remaining six reach the Silver with an average score equal to 50.7. So our 212 objective to achieve LEED ® certification for all buildings while maximizing energy 213 performance has been achieved. The study shows that there is a technical feasibility: 214 the credits are between 42 and 54 (see Fig. 4).

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The economic evaluation was conducted considering the costs of retrofits (hard 216 cost) but also soft costs and the cost of Green Building Certification Institute (0.4%).

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Cost items considered in the economic evaluation concern: Building envelope 218 retrofit cost, heating systems retrofit cost, ventilation systems cost, solar PV cost 219 (for the installation of a polycrystalline PV system), Green Building Certification

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The cost of building envelope retrofit is the highest cost item with 53.2% of the 225 total cost; heating systems retrofit is the second largest cost item with 29.7% of the 226 total cost (the cost of building envelope and heating systems retrofit is therefore 227 82.9% of the total cost).

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The economic issue remains, however, and is even greater when operating inside 229 the public market, which is made up of public buildings such as schools.

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The following question arises: should in the sector of public building retrofit 231 strategies should be limited to an improvement of the energy performance or should 232 aim to improve the sustainability as well? to improve the conditions for learning.

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The research presented and discussed in this chapter highlights a great interest in 243 dealing with the issue of energy retrofit of school buildings. In assessing the oppor-244 tunities for reducing energy requirements, however, the economic aspects that often 245 constrain actions must be considered.

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In the first and second case study discussed we can easily confirm that, while it The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.