## 4 Conclusions  
A detailed LCA was carried out of an innovative system for heating and domestic hot water production, including sensible, latent, and electric storage. The LCA was performed comparing the results to a selected reference system. The LCA was carried out for a functional units m\({}^{2}\) of living floor area, and using two different indicators, ReCiPe and IPCC GWP (20 years and 100 years). The operational data were given by simulations as explained in Section 2.2.  
Results show that when using the ReCiPe indicator, the overall impact of the innovative system is lower than that of the reference system. In all damage categories, the impact of the innovative system is lower than that of the reference system. Again, the impact of the manufacturing and disposal stage is higher than for the operational stage, but this difference is compensated with the one of the operational stage (lower in the innovative system).  
On the other hand, when using the IPCC GWP indicator, the impact of the innovative system is lower than that of the reference system. The impact of the operation stage clearly makes the difference, since although in the manufacturing stage, the impact of the innovative system is very similar than that of the reference system, the decrease in the operational stage in the innovative clearly compensates for it.  
If the contribution of the different subsystems is analyzed, it can be seen that the sensible heat storage and the PV panels are the subsystems with higher impact (both with a contribution of 34% and 30%, respectively), while the high-temperature latent TES storage  
Figure 7: Contribution of the refrigerant to the overall system change in the refrigerant lifespan: (**a**) 15 years; (**b**) 10 years; (**c**) 5 years; (**d**) 1 year.  
sub-system has a contribution of 20%. The other two sub-systems considered, the electrical storage and the compression heat pump, have a contribution of 10% and 6%, respectively.  
Finally, the parametric study carried out analyzed the influence of the impact of the refrigerant. The analysis was conducted taking R134a as baseline, since this is the refrigerant found in the used database Ecoinvent. The analysis performed on changing both the impact of the refrigerant or the amount of refrigerant shows that the contribution of the refrigerant to the overall impact of the studied system does not vary enough to consider that decreasing the impact of the refrigerant will contribute to decreasing the overall impact of the innovative system.  
Conceptualization, L.F.C.; G.Z. and V.P.; methodology, L.F.C. and N.L.; formal analysis, G.Z.; investigation, N.L.; F.T. and V.P.; resources, L.F.C. and A.F.; data curation, L.F.C.; writing--original draft preparation, N.L. and L.F.C.; writing--review and editing, G.Z.; V.P.; A.F.; M.D. and F.T.; visualization, N.L.; supervision, L.F.C.; project administration, L.F.C.; A.F. and M.D.; funding acquisition, L.F.C.; A.F. and M.D. All authors have read and agreed to the published version of the manuscript.  
Not applicable.  
The data presented in this study are openly available in DataverseCat repository ([[https://dataverse.csuc.cat/](https://dataverse.csuc.cat/)]([https://dataverse.csuc.cat/](https://dataverse.csuc.cat/)) (accessed on 23 March 2021)) at doi:10.34810/data44.  
The authors would like to thank all partners that contributed in the inventory (CSEM Centre Suisse d'Electronique et de Microtechnique SA-Recherche et Developpement, Ochsner Warmpeumpen GmbH, Pink GmbH, AKG Verwaltungsgesellschaft mbH, and National Council or Research Italy, Institute for Advanced Energy Technologies).  
The authors declare no conflict of interest.