solar modules solar energy uk renewables industry solar panels solar pv industry solar technology mcs 012 trends in pv market solar battery storage policy planning solar panels technology mc4 connectors mc4 staubli connectors mc4 original connectors solar connectors solar dc connectors dc connectors mismatch solarwatt glass-glass panels solar panel wiring how to wire solar panels connect solar panels daisy chain wiring leapfrog wiring skip wiring renewables installations pv certification mcs certified n-type solar cell technology silicon solar cells pv solar topcon solar cells perc solar cells sig energy sigen stor sigenstore sigenstor sigenergy ess all-in one energy storage solution solar battery energy controller ai artificial intelligence stackable green solution innovation G100 Issue 2 EREC Recommendation G100 Issue 2