**4. Discussion**

Three considerations can be identified from the study and the obtained results: The city-campus relationship (1); the applicability of the strategic analysis; (2) and the integration of tools (3).

First, the single location of the campus within the urban network of the city of Donostia-San Sebastián results in a direct relationship between the two evaluated elements. At the same time, strategies or commitments of the city in terms of mobility or energy e fficiency directly a ffect the two evaluation scales. However, university campuses normally develop their own strategies without considering the trends or commitments of the city in which they are located. This study is an attempt to reflect how strategies defined at the municipal level can be applied at the university campus level and how these actions environmentally impact the city. In this study, the small university campus contributed only 1.4% of the total GWP emissions of the city in 2015. The application of all of the strategies proposed in this study (scenario 13), reduces the total GWP emissions of the campus by 34.5% (with respect to 2015). This reduction is greater when the simulated reform scenario in NEST is in conjunction with the city and applying the municipal plans. Considering previous research carried out on the whole of the Basque Country University [38], where university campus reform scenarios based only on university policies were applied, (without taking into account municipal policies), the reduction was smaller.

The second consideration shows the need to constantly monitor the implementation and applicability of action strategies defined by documents such as SEAPs, which have a long perspective (10 years). The socio-economic or normative changes that occur over this timeframe can significantly alter any proposed scenario, reducing or eliminating the feasibility of application of a previously proposed strategy. The same happens with the university's plans that are linked to the Basque Government, following long-term European directives (2020, 2030, and 2050). Taking into account the socioeconomic changes that also a ffect the university, it can be periodically simulated, in a few weeks, what is the most sustainable option. However, from the comparison between the previous simulation carried out and the monitoring of the University consumption collected between 2015 and 2018, it shows that, although the simulation allows detecting the most sustainable reform scenario, in the case of the university the simulation data has su ffered greater variations than in the city, so the university must take this in consideration, and corroborate the simulation data with constant monitoring.

The third consideration shows the potential of tools, such as NEST, to evaluate and define future scenarios. This study has shown that it is not always easy to obtain values for the energy consumption or GWP emissions that are in agreemen<sup>t</sup> with monitoring data. However, in this study, the highest di fference between the monitored values and the NEST simulation results was 21% (mobility of the university campus), which could be viewed positively. Most significantly, the monitoring information for the city or the energy consumption of all of the buildings of the university campus were obtained by di fferent public entities over a period of three years, whereas the modelling and calculation process was completed in three weeks for the city and one week for the campus. In addition to the rapidity of the simulations, this type of tool can be used to calibrate the input data to the actual application of each strategy. In this way, the evaluation model becomes a dynamic model that can be adapted to each moment, facilitating rapid decision-making on the most sustainable design solution. Lastly, these tools enable the potential of strategies to be analysed at either the municipal or local level, including for a given and smaller area of a municipality. In this way, those responsible for the university campus can estimate the reduction in GWP emissions of the campus from the application of municipal strategies or perform a parallel analysis of the e ffect of these strategies on the city. For this last consideration, di fferent public actors of the city of Donostia-San Sebastián and the university campus, who currently work and choose strategies separately from each other, must work together in order to optimise resources, enabling the design, analysis, and quantification of the impact of each decision at di fferent scales.

The evaluation of the proposed scenarios, wherein the strategy of the university is aligned with the municipal policies of the city of San Sebastian, can be used to achieve higher levels of sustainability. In this case, it has been possible to verify how a scenario of joint refurbishment between the city and the university, according to municipal sustainability plans (SEAP), allows cities to assure compliance with agreements at European level such as the Global Covenant of Mayors for Climate and Energy. Therefore, it is proven that the university can contribute to the environmental improvement of cities. The sustainability of a university can no longer be limited to improving a particular faculty building or the sustainability of the university as a whole but requires the establishment of strategies to develop synergies with the municipal environmental policies of the cities in which university campuses are located.

**Author Contributions:** Conceptualization, I.L., X.O., and C.M.; Investigation, I.L., X.O., and C.M.; Methodology, I.L. and X.O.; Data curation X.O.; Supervision, I.L. and C.M.; Writing original draft, I.L. and X.O.; Writing—review and editing: I.L., X.O., and C.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** The authors thank the UPV/EHU (Vicerrectorado de Innovación, Compromiso social y Acción cultural) for supporting the development of this type of work to achieve a more Sustainable University.

**Conflicts of Interest:** The authors declare no conflict of interest.


**Table A1.** Monitored data for the campus of Donostia-San Sebastián.

**Appendix A**


**Table 2.** Complete table of data according to the SEAP, summarized in Table 3.

**B.**

*Sustainability* **2020**, *12*, 774


**Table 2.** *Cont.*

*Sustainability* **2020**,*12*,774


**Table 2.** *Cont.*
