FOX ESS HQ3

What the FOX ESS HQ3 does

A hybrid inverter runs both the solar array and a home battery: it supplies the home from the panels first, stores the surplus and draws on the battery when the sun goes down. The FOX ESS HQ3 range spans 5 kW to 15 kW of AC output, suiting arrays of about 5–6.5 kWp at the small end and 15–19.5 kWp at the large end, as installers commonly size the panels up to 30% above the inverter's rating.

In Germany, arrays of the same size produce about 4,500 to 13,500 kWh a year, assuming a conservative 900 kWh per kWp. For the smallest model, that is worth €347 a year fed into the grid at 7.70 ct per kWh, and up to €1,665 used at home instead of buying power at 37.0 ct.