The company says the new PowerStream features that will be available through its mobile app “include cutting-edge technologies tailored to specific critical needs” and that by only making them available through a subscription model, users won’t have to pay for advanced features they don’t use. EcoFlow also says the paid model will allow the company to continue “maintaining and developing these niche but critical new features.”

EcoFlow also assures users that it has no plans to lock its apps and other software features already available on its power devices behind a paywall. “All existing features available to PowerStream users remain unaffected. The core functions of these devices will never be subject to payment thresholds, and you will never be required to make additional software payments to use your devices normally.”

The PowerStream Balcony Solar System uses solar panels, a large portable battery, smart plugs, and a compact microinverter to deliver cheaper solar-generated power to other devices and appliances around a home using standard wall outlets. Using EcoFlow’s mobile app, users can specify how much power from the solar panels is used to keep devices like washing machines and coffee machines running, or how much is used to charge up batteries for times when solar power generation is reduced.

Details about the new features being tested for the PowerStream system — including added functionality, when they’ll be available to all users, and how much they’ll cost — haven’t been revealed by EcoFlow.