This video documents the troubleshooting and rectification of a tens of thousands of pounds solar and battery storage system (My Energy system with a 20 kWh Libby battery) that was significantly underperforming for the customer. The primary issues identified were incorrect configuration of system limits, improper placement of a key current transformer (CT) for the Solar Edge inverter, outdated firmware across various devices (Libby, Zappy, Eddi, Solar Edge inverter), and a lack of proper inter-device communication. The investigation revealed that the main garage supply cable was capable of handling much higher loads than the installer's stated limit, making the imposed battery charge/discharge limits unnecessary and inefficient. The technician successfully updated all firmware, reconfigured system limits, corrected the CT placement, and ensured all devices were communicating and paired correctly. The system is now optimized to effectively store and utilize solar energy, with the video concluding that the initial problems likely stemmed from the original installer's inexperience with the then-new product.
Troubleshooting an Underperforming Solar & Battery Storage System
0:00 Initial Problem: A customer's 20 kWh battery storage system, installed to complement a 6.3 kW solar setup, was only charging at half capacity (1 kW) despite costing tens of thousands of pounds.
0:48 Installer's Claim & Misdiagnosis: The original installer incorrectly attributed the low charging capacity to a 30-amp input limit to the garage, which the investigation later disproved.
1:38 Cabling & Capacity: Initial visual inspection of the garage supply cable suggested a 6mm cable, potentially justifying a limit, but later confirmed it was a 10mm Steel Wire Armored cable capable of handling 50 amps, with a 50-amp fuse, rendering the low limits unnecessary.
2:06 Battery & Solar Performance: The system, using Octopus Intelligent Go for overnight charging, was discharging slowly, and solar charging was also limited (2.1 kW instead of the inverter's 5 kW capacity), indicating an imposed system limit.
3:27 Missing Data & Functionality: The My Energy app showed no grid history, and the Eddi hot water diverter was not activating due to a lack of excess power, suggesting broader communication or configuration issues.
4:09 Inverter Location & Access: The 5 kW Solar Edge inverter, though a good system, was installed in the customer's loft, making it difficult to access for maintenance or checks, highlighting poor installation practice.
5:21 Device Communication Issues: The My Energy display was not showing the Libby battery or Zappy car charger, only the Eddi, indicating devices were not properly synced or paired. Crucially, no Current Transformers (CTs) were connected to the main unit, and CTs should have been in place for grid, solar, and local load monitoring.
6:22 Firmware Updates: A key step in resolving the issues was performing firmware updates across all devices (Libby, Zappy, Eddi, Solar Edge inverter) to eliminate potential bugs and ensure compatibility.
8:34 Safety Concern (Immersion Heater): The immersion heater lacked a "double stat" (backup thermostat), a critical safety feature to prevent water boiling and tank rupture, which was noted for a report.
11:26 Incorrect CT Placement (Solar Edge): The Solar Edge Current Transformer (CT) was found to be incorrectly placed around the house's consumer unit tail instead of the main property tail, leading to inaccurate import/export readings for years. This was corrected.
12:29 Installer Competence Questioned: The My Energy installer's actions (e.g., not moving the Solar Edge CT, lazy labeling of circuits, feeding Modbus with undersized flex) suggested a lack of education or experience with integrating different renewable energy systems.
16:44 Removing Limits: The discharge limit on the Libby battery was removed (from 18 amps to 22 amps, its full rate), as load testing confirmed the garage cable could safely handle full charge/discharge alongside other loads.
20:45 Recommended Additional Protection: Installing another CT on the garage supply cable was recommended as an extra layer of protection (belt and braces) to automatically ramp down Zappy and Libby if the unlikely event of 50-amp draw was reached.
21:37 System Rectification & Outcome: After updates and reconfigurations, solar was visible on the Zappy, devices were communicating, and the date was correct. The system is now fully functional and significantly more effective.
22:01 Automatic Updates: The customer was advised that with a stable internet connection, the system would perform automatic firmware updates, removing the need for manual intervention.