**5. Conclusions**

Utilization of flexibility in the future Smart Grid will occur through information and communication technology (ICT) regardless of the exact market design. In the future, it is unknown whether a steady load profile as demonstrated in this paper will be the true load shape objective of a Smart Grid. However, because no operational Smart Grid exists that can be used to define the load shape objective

in the Dutch context, and since the method introduced in this article has proven to be successful after implementing in the building, it is safe to conclude that the baseline approach is adequate for demonstrating load flexibility for a future electricity grid setting.

As an extension of this work, in the future, the baseline approach can be extended to a dynamic baseline which varies hourly depending on the grid's needs. BESS flexibility, as well as other sources of flexibility (e.g., HVAC system flexibility), could then be integrated to achieve even greater flexibility. The optimal load shape could be determined based on the combination of the predicted energy demand of the buildings or neighborhoods according to the Smart Grid's needs. However, this work did not include an economic assessment of a Smart Grid using PVs and a BESS. An extension of this study could also be made with an added economic assessment. However, in such a study, a time-of-use tari ff structure and the economic value of provided flexibility should be incorporated.

The built environment has the potential to contribute to maintaining a reliable grid by actively participating in future grids. The case study building provided a perfect opportunity for demonstrating and investigating such characteristics.

**Author Contributions:** R.C., Conceptualization, Methodology, Software, Validation, and Writing—Original Draft Preparation; S.W., Methodology, Supervision, and Writing—Original Draft Preparation; J.v.d.V., Resources, Review, and Supervision; P.N., Review; W.Z., Funding Acquisition, Review, and Supervision. All authors have read and agreed to the published version of the manuscript.

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

**Acknowledgments:** This work was conducted in collaboration with the Netherlands Organization for Scientific Research (NWO) Perspective program TTW Project B (14180) "Interactive energy managemen<sup>t</sup> systems and lifecycle performance design for energy infrastructures of local communities" (https://ses-be.tue.nl/). We wish to express our gratitude to Kropman Installatietechniek for providing access to necessary data, helping with the data collection process, and providing the building for experiments.

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