EcoFlow STREAM vs Anker SOLIX RS40P: Which Kit to Buy UK 2026?

When compliant plug-in solar kits hit UK retail shelves, two brands will dominate the conversation: EcoFlow and Anker SOLIX. Both have massive European track records from Germany's Balkonkraftwerk market, both have UK-ready products, and both are competing for the same buyer.

Here's how the EcoFlow STREAM and Anker SOLIX RS40P compare on everything that matters.

The Basics

Both systems cap at 800W AC output as required by UK regulations. The Anker's slightly higher panel wattage (890W vs 800W) means it reaches the 800W inverter cap more easily in marginal conditions — a genuine advantage in cloudy UK weather.

Setup and Installation

EcoFlow STREAM — setup is designed to be completely tool-free. Panels connect to the integrated micro-inverter via pre-wired MC4 cables, and the AC output plugs into a standard UK 13A socket. The EcoFlow app walks you through the process with guided setup. Typical installation time: 30-45 minutes including mounting.

Anker SOLIX RS40P — similar tool-free setup. The APsystems micro-inverter is integrated into the system, with pre-attached cabling. The Anker app handles commissioning. Setup time is comparable to EcoFlow.

Both brands include basic mounting hardware for balcony railing installation. For wall or ground mounting, you'll need additional brackets — see our tilt mount guide for options.

Verdict: essentially tied. Both have streamlined the setup process to consumer-appliance simplicity. Neither requires electrical knowledge.

Best overall

EcoFlow PowerStream 800W Kit

~£799 estimated

• 800W dual-panel balcony or garden kit
• 600Wh plug-in battery included
• App with live monitoring & smart scheduling
• Balcony, garden & flat-roof mount options

View on EcoFlow →

BSI-compliant kits expected from July 2026. Prices are estimates.

Monitoring and App Experience

EcoFlow app — shows real-time generation, daily/monthly totals, and historical data. The interface is polished and easy to navigate. EcoFlow's broader ecosystem (DELTA 2 battery, other products) means the app is actively developed and regularly updated. If you plan to add an EcoFlow battery later, having everything in one app is a genuine advantage.

Anker app — functionally similar. Real-time wattage, daily totals, historical graphs. The interface is clean but marginally less feature-rich than EcoFlow's. Anker's ecosystem is growing (the SOLIX C1000 battery integrates) but isn't as mature.

Verdict: EcoFlow has a slight edge on app quality and ecosystem breadth. If you plan to stay within one brand's ecosystem for battery storage, this matters.

Build Quality and Durability

Both kits use monocrystalline panels with aluminium frames, tempered glass, and IP67/IP68-rated connectors. Build quality is comparable — these are premium consumer products, not budget hardware.

EcoFlow uses Hoymiles micro-inverters, which have the largest installed base globally. Hoymiles has a well-documented track record from Germany's market.

Anker uses APsystems micro-inverters, which are the second most popular in the European plug-in solar market. APsystems also has a strong track record.

Both inverter brands have known monitoring connectivity quirks — see our monitoring app troubleshooting guide. Neither is significantly more reliable than the other based on available data.

Verdict: tied. Both are well-built and use proven components.

Real-World Output

The Anker's higher panel wattage (890W vs 800W) means its panels are slightly oversized relative to the 800W inverter cap. This is actually advantageous: oversized panels ensure the inverter reaches its maximum output more of the time, particularly in non-ideal conditions (cloudy weather, sub-optimal angles, partial shading).

In practice, both systems will hit the 800W cap during peak summer hours. The difference shows up on overcast days and in shoulder seasons (spring/autumn), where the Anker's extra headroom translates to marginally higher output — perhaps 3-5% over a full year.

Verdict: Anker has a slight edge on annual generation due to panel oversizing.

Battery Compatibility

EcoFlow — pairs natively with the EcoFlow DELTA 2 and other EcoFlow batteries. The solar panels can charge the battery directly via MC4 (bypassing the micro-inverter) or indirectly via AC. The app manages both solar and battery in one interface.

Anker — pairs with the Anker SOLIX C1000 and SOLIX range. Similar direct/indirect charging options. The Anker app manages the combined system.

If you plan to add battery storage, staying within one brand's ecosystem simplifies setup and monitoring. The DELTA 2 is slightly cheaper than the C1000, giving EcoFlow a cost advantage on the combined solar-plus-battery package.

Verdict: EcoFlow wins on battery-paired value. The DELTA 2 is cheaper and more established.

Price and Value

The EcoFlow STREAM is expected at ~£699; the Anker RS40P at ~£649. The £50 difference is modest — roughly the cost of a Tapo P110 and a set of cable ties.

If you're comparing purely on price, the Anker wins by £50 with marginally higher generation potential. If you're comparing on ecosystem (battery, app, brand support), EcoFlow's deeper product range and more mature app give it an edge.

Our Recommendation

Buy the EcoFlow STREAM if: you plan to add battery storage later (the DELTA 2 ecosystem is stronger), you value the app experience, or you want the largest possible support community and accessory range.

Buy the Anker SOLIX RS40P if: price is the primary concern, you want marginally better output from the oversized panels, or you prefer APsystems inverter technology.

Either way: both are excellent kits. The performance difference is under 5%. Your placement, orientation, and self-consumption behaviour will matter 10× more than the kit choice. See our installation guide for getting the most from whichever kit you choose.

Buy the EcoFlow STREAM on EcoFlow.