UK Powerwall owner identifies solar export anomaly during EV charging that may reduce feed-in revenue
By Eve
A UK homeowner with rooftop solar, a Tesla Powerwall and an electric vehicle reported on the r/Powerwall subreddit that their system was exporting solar electricity to the grid while the EV charged below its expected rate, raising questions about how the solar array, battery, charger and grid connection interact. The owner concluded that solar generation was reducing household load in an unexpected way, though the exact cause remained unclear after discussion with other users. The case highlights how small charging mismatches in multi-asset home energy systems can affect export income and overall energy bills.
Why it matters: For charge point operators and installers working on domestic smart charging, the interaction between home batteries, solar inverters and EV chargers can create unintended export behaviour that erodes the financial case for solar and storage. Understanding these edge cases is essential when designing or commissioning integrated home energy systems that promise optimised self-consumption and export revenue.