99% Solar Efficiency? Growatt THOR 22kw EV Charger Review | TechManPat

What the 22kW rating means

The Growatt THOR 22AS-P is a three-phase AC EV charger with a listed maximum output of 22kW and 32 amps. It does not convert AC power to DC for the vehicle battery; that task is handled by the car’s onboard charger. As a result, a 22kW wallbox does not guarantee 22kW charging. The review notes that most Teslas in Australia are capped at 11kW for AC charging.

The charger includes IP65 weather protection, built-in RCD and DC fault protection, and a 5m cable. Charging can be started through the app, an RFID card or by simply plugging in. The cable length and fixed design need to be considered when planning the installation and the position of the vehicle’s charge port.

Charging modes and controls

Fast mode uses available renewable energy or grid power and can be controlled with a timer, a required charging capacity in kilowatt-hours or a charging budget. Off-peak mode schedules charging during the local utility’s off-peak period.

PV linkage mode communicates with the Growatt solar system and adjusts charging according to surplus solar production. The review says the charger can be configured to disable grid imports, so the car charges only when solar power is available. If clouds reduce generation, charging scales back.

Manual boost temporarily switches to maximum power before returning to PV linkage after the selected timer expires. Smart Boost allows a charging target and deadline, such as needing a specified amount of energy by the following morning. It prioritises solar, then draws only enough from the grid to meet the target.

Load balancing and solar self-consumption

With additional CT clamps, the charger can monitor household consumption and reduce the vehicle’s charging rate when other loads, such as an oven or air conditioner, are operating. This is intended to prevent the home’s power limit from being exceeded.

Using Home Assistant data, TechManPat reports that the charger achieved almost 99% solar consumption in the tested smart modes with a 10kW solar system. Before the charger was installed, reported solar self-consumption was approximately 60% to 75%, depending on the day. The 99% figure refers to using available solar energy rather than exporting it to the grid, not to converting all incoming sunlight into usable energy.

The three-phase residential limitation

The main limitation for smaller homes is the minimum power needed to start three-phase charging. The review says the charger was set to a minimum of 4.1kW, based on the approximately 6A minimum current in the EV charging standard. A single-phase system can start at around 1.4kW, with approximately 2kW needed for a Tesla to charge properly, so single-phase charging may suit smaller solar arrays better.

The 22kW model is therefore positioned towards larger homes, businesses and sites with substantial solar and inverter capacity. The review suggests that around a 15kW inverter and 20kW of panels are needed to make 22kW daytime charging practical, while describing a 10kW inverter and 15kW of panels as a suggested residential minimum for faster excess-solar charging.

Real-world use and other considerations

In the tested home, which has a 10kW inverter and 13.5kW of panels, the charger averaged approximately 5kW to 7kW of solar charging during the day while the home used around 2kW. Charging the car with smaller daily top-ups allowed both the home battery and vehicle to be replenished without relying on large paid charging sessions. The review estimates savings of about $100 per bill, or approximately $50 per month, using a daytime electricity rate of roughly 9 cents per kilowatt-hour.

The charger also includes RFID access, 4G connectivity and OCPP 1.6 support, features that may be more useful for businesses, car parks and fleet management than for a typical home. For Tesla owners, the cable handle does not include a button for opening the vehicle’s charge-port lock, requiring the Tesla app or the car door instead.