## 4 Conclusions  
With the help of the statistical data analysis method, we can draw the following conclusions relevant for the design of photovoltaic systems.  
String inverters are unlikely to interfere with radiocommunication when the PV system is installed according to recommended standards, rules, guidelines, and regulations.  
Photovoltaic systems with module optimizers tend to have higher emissions. They show a signature of 200 kHz separation in the ranges 3.2-6.4 MHz and 12.6-21.2 MHz, when using aluminum-framed monofacial modules. The presence of these frequency components makes it more likely that inverters with module optimizers interfere with radiocommunication.  
Our study showed that changes in cable management and earthing play a lesser role in electromagnetic emission behavior than the choice of solar inverter concept and module type.  
To the best of our knowledge, this study shows for the first time that the change to bifacial glass-glass modules without an aluminum frame substantially increases radiated electromagnetic emissions. Bifacial glass-glass modules in combination with module optimizers show a more pronounced 200 kHz signature and emit in a broader frequency range than systems with aluminum-framed monofacial modules.  
Conceptualization, D.K. and U.L.; methodology, D.K. and U.L.; investigation, D.K. and U.L.; measurements, D.K. and U.L.; data processing and visualization D.K.; validation, D.K.; formal analysis, D.K.; writing--original draft preparation, D.K.; writing--review and editing, D.K., M.B., A.A. and U.L.; supervision, M.B. and A.A.; funding acquisition, D.K., U.L. and A.A. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Swedish Energy Agency, grant numbers P2020-90239 and 50982-1 and grant numbers P2021-90275 and 52693-1.  
The data presented in this study are available on request from the corresponding author.  
Figure 7: Summary of peaks above the highest background (orange) and peaks above the EMC limit (blue) for combinations MO_SE_yz, BI_SE_yz, MO_K_yz, and BL_K_yz. Each boxplot shows the minimum, median, and maximum number of peaks per system combination. The two circles mark the location of the two compared systems in Figure 6a,b. They represent the minimum difference of peaks for system combinations MO_SE_yz and BL_SE_yz, while the median difference is marked with black lines.  
**Acknowledgments:** The authors would like to thank the Swedish Energy Agency for funding the projects: \"Method to detect and to prevent EMI from PV installations\" Project nr: 50982-1 (solEMC) and the \"Solar Electricity Research Center Sweden\" Project nr: 52693-1 (SOLVE) as a national center of excellence. The authors would like to thank the Swedish National Electrical Safety Board, the solEMC project member [PERSON] from Friendly Power and the Swedish radio council for fruitful discussions. We also thank the internship students [PERSON] and [PERSON] assisting in the measurement campaign, [PERSON] from Solfamiljen, and diverse solar energy engineering master students from Dalarma University assisting in building the different PV system combinations. Thanks is extended to [PERSON] and [PERSON] for the language support throughout the writing process.  
**Conflicts of Interest:** The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.