**5. Conclusions**

The occurrence of the black swan in December 2019, which is undoubtedly the emergence of the SARS-CoV-2 coronavirus epidemic in the Chinese province of Hubei and its spread throughout the world by the end of the first quarter of 2020, triggered a series of events that changed the face of the known so far in the world. Some of the industries most affected by the scale of unprecedented restrictions in individual waves of the pandemic consist of those areas of activity where people-to-people contact is on the agenda so far, such as the catering and hotel industries.

The picture of the world affected by the pandemic in the context of the energy demand of these sectors is quite different from its previously known form. The high correlations between the profiles of electricity demand in restaurants, cafes and hotels and the profile of power demand in the national power grid or production profiles of photovoltaic sources reaching the Pearson or Spearman correlation coefficients of 0.6–0.7 for the pre-pandemic period a significant change. Especially in the case of the hotel industry, there is a noticeable decrease in the volumes of electricity demand as well as their daily variability that is different from the demand profile in the network.

In the case of restaurants and cafes, these dependencies still remain at a moderate level. which is tantamount to a destabilizing impact on the parameters of the distribution network. At the same time, these industries appear to be potentially effective entities to install photovoltaics for the self-consumption of more expensive electricity. This is confirmed by the relatively high determined index of the hypothetical self-consumption of energy from own PV sources in the analyzed enterprises.

A positive correlation with a moderate value of the coefficient of the order of 0.5 means that these enterprises currently consume relatively expensive energy which in the context of the introduction of dynamic tariffs in 2027 justifies the interest in investing in their own PV source. Proper selection and flattening of the resultant profile of energy demand from the grid may also reduce costs and create preferential conditions for DSOs.

It is worth noting that the self-consumption coefficient, unlike the industries initially associated with the energy transformation, in the case of broadly understood services. has a justified potential to increase due to the increase in EV popularization. Especially in the case of restaurants located on busy thoroughfares car chargers could be an interesting supplement to the PV installation subject to preferential conditions. Such a service would be an additional incentive to stop at this specific place, which would translate into an increase in the competitiveness of the company's offer. The economic efficiency of such a solution seems to be a natural development step for the research presented in this article.

In the case of hotels, with the indicated values of correlation, the justification for such solutions could be found by entities focused on business customers and conferences. Intelligent energy management system could be integrated into the Vehicle-2-Grid and/or Grid-2-Vehicle model. In this way, the hotel could obtain preferential conditions and/or create an additional level of relationship with the customer by offering him a financial advantage in return for providing a vehicle for the V2G/G2V model.

The directions of the further development of research problem presented in this article may be:


**Author Contributions:** Conceptualization, S.K., M.S. and D.M.; methodology, S.K. and M.S.; validation, S.K. and D.M.; formal analysis, S.K. and D.M.; investigation, S.K., M.S. and D.M.; resources, D.M. and S.K.; writing—original draft preparation, S.K., M.S. and D.M.; writing—review and editing, S.K. and D.M.; visualization, S.K. and D.M.; supervision, S.K. and D.M.; project administration, S.K. and M.S. All authors have read and agreed to the published version of the manuscript.

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

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

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